Agriculture

Assessing and Combating the Enteric Methane Contributions of Ruminants

mbonaccorso 19 Comments

Authors: Melissa Bonaccorso (Natural Resource Conservation); Morgane Golan (Animal Science, Pre-Vet); Ben Phaneuf (Building Construction Technology)

In a new effort to better quantify the methane emitted by livestock, researchers are utilizing methane-collecting backpacks on cows.

Most of us have the best intentions when making decisions at the grocery store – we often try to choose what is best for our health, and many of us have environmentalism in mind, as well. It can be difficult to know what is best, and all the contradictory information out there can leave us frustrated and confused. It seems that every few months there is a new set of rules for how we are supposed to eat: vegan, vegetarian, antibiotic-free, gluten-free, cage-free, GMO-free; and when it comes to beef, grass-fed is now all the rage. Unfortunately, if environmental sustainability is your motive, grass-fed beef actually does more harm than good. Ruminants such as cattle, sheep, and goats, are animals that are able to subsist on plant matter because they have a stomach compartment, the rumen, in which microorganisms digest these cellulose products. However, this form of digestion, known as enteric fermentation, comes at a cost. The microbial ecosystem of the rumen generates methane as a byproduct of this fermentation, in a process called ruminal methanogenesis (Lassey 2006). Methane (CH4) is a greenhouse gas, and is of critical importance because it has a global warming effect that is 28-36 times that of carbon dioxide (EPA). Nearly half of all human-caused methane emissions come from agriculture, and livestock contributes nearly 70% of CH4 emissions from the agricultural sector (Vergé et al. 2008, p.132; Lassey, 2006; Wysocka-Czubaszek 2018). In the context of the US specifically, methane accounts for 10% of our total greenhouse gas emissions, and 26% of these methane emissions comes from enteric fermentation – the second-highest portion next to natural gas and petroleum systems (EPA). While its concentration in the atmosphere is much lower than that of CO2, methane is 20 times more effective at trapping heat than carbon dioxide is, and has the potential to contribute 18% of the total expected global warming up to the year 2050, next to carbon dioxide’s 50%  (Milich, 1999). Thus, while CO2 tends to get the most public attention for its contributions to climate change, methane is a much more potent greenhouse gas, which calls for more significant consideration.

An average of 30 million animals per year are slaughtered for the beef industry in the US, and an average of 2 million animals, with an additional 3.4 billion pounds of beef, are imported to the US from Canada annually (ERS, 2015). In addition, about 9 million milk cows are active in the US in 2016 alone (statista.com). In all, approximately 20 billion pounds of beef is consumed in the US each year, accounting for approximately half of the American dietary carbon footprint (Waite, 2018). The amount of CH4 emissions from ruminants in 2016 was equivalent to 170 million metric tons of CO2 (Center for Sustainable Systems, 2018). To put these numbers into context, the effect of greenhouse gas emissions produced by annual US beef consumption is equivalent to that which would result from a car driving around the entire Earth 22,000 times (space.com; ewg.org). In response to the severity of methane output via enteric fermentation, the scientific community has become increasingly concerned with identifying resolutions that are considerate of productivity within the agricultural sector, as well as environmental efficiency.

Significant enteric methane production, and the overall increasing trend in GHG emissions by the beef and dairy industries, are symptomatic of a high demands for livestock products (Place, 2016). Many environmentalists and animal-rights activists advocate for a drastic decrease in or even total elimination of beef and dairy consumption in the American diet. Reduction in meat and dairy consumption is certainly linked to a lower personal environmental impact: the greenhouse gas emissions associated with the average meat-eater’s diet are about 1.5 to 2 times those of vegetarians and vegans, respectively (Scarborough, et al. 2014). But most people are resistant to altering their diet in such a radical way, due to a plethora of social and physical barriers; global demand for meat products is actually increasing at a rate faster than land availability can accommodate (Kwan, 2011; Jenkins, 2004; Verge, 2008). In fact, demand for beef and dairy products in the US is expected to increase 70% within the next 36 years (Place, 2016). Although veganism and vegetarianism can help reduce total greenhouse gas emissions, we simply cannot rely on everyone to adopt these lifestyles if we are to make significant changes with haste. In addition, campaigns to reduce meat consumption pose a threat to cattle farmers’ incomes. Harsh restrictions on the beef and dairy industries, or campaigns to reduce the consumption of these products across the nation and world, are both insufficient and would also pose a threat to those whose livelihoods depend on these industries. For these reasons, research teams including veterinarians, environmental specialists and other invested individuals, are collaborating to identify strategies for reducing ruminal methane emissions, without harming invested parties. To minimize the impact of ruminal methane emissions without negatively affecting animal welfare and the livelihoods of stakeholders, we propose the integration of dietary supplements into ruminal feed to naturally inhibit methanogenesis.

One of the most promising methods of reducing ruminal methanogenesis without posing a threat to the industry or the animals is through supplementation of the animals’ diets. Since feed efficiency and methane production are intrinsically linked, ruminants reared on cellulose-based diet, such as those destined to become the beloved “grass-fed” beef, will produce more methane, and for a longer time than they might otherwise, since the cellulose-based diet is not conducive to optimal growth of the animals (Tirado-Estrada et al., 2018). Experts in the field have acknowledged that completely altering the diet of every ruminant on earth is not feasible: grain-based diets can be costly and are often inaccessible (Tirado-Estrada et. al., 2018). It is possible and cost-effective, however, to improve the digestibility of the livestock diet by replacing some of the fiber content with protein-rich concentrates, while still utilizing the typical pasture-based diet. Increasing the digestibility of the diet of dairy and beef cattle can reduce methane emissions in two ways: first, by helping these cows reach market weight sooner, thereby limiting the amount of methane that each cow can produce throughout its life, and second, by inhibiting the process of methanogenesis in the rumen. Any compound with a high protein/low fiber content would be a fine contender for the improvement of the ruminal diet, but those that are naturally sourced, readily available and less costly are most ideal for the animals, the environment, and stakeholders. An excellent option which meets this criteria has been identified: mangosteen peel powder (MSP). Mangosteen peel powder, or Garcinia mangostana, is very highly regarded among animal nutritionists, because it does not negatively affect the crucial microbial populations of the rumen, but can reduce the population of methanogens, the microorganisms most responsible for methane production, by up to 50% in a safe manner (Polyorach et. al., 2016). The utilization of MSP in feed has been found to significantly reduce methane production between 10-25% (Wanapat et al. 2015; Manasri et al 2012; Polyorach et al. 2016). Aside from reducing the population of methanogens, protein-rich plant concentrates present in mangosteen peels, called saponins and tannins, have also been found to minimize the growth and activity of methane-producing protozoa in the rumen, without inhibiting their function entirely (Wallace et al, 2002, Patra 2011). Supplementing the diet with naturally derived plant compounds such as this effectively reduces methane production, and does so without causing significant consequences to the animal’s microbial system or putting the animal at risk for ruminal disease (Patra, 2010).

Dietary additives are already widely used to supplement cattle feed, which makes further supplementation feasible once high-protein supplements, like MSP, are made readily available in the national market. For example, Rumensin is a feed additive that has been used in the cattle industry for over 4 decades (Greenfield et al., 2000). The active ingredient in Rumensin is a coccidiostat, meaning that it is an antibiotic specifically geared at killing coccidiosis bacteria in the animal body. Rumensin is an attractive product because of its prevention and control of disease, as well as its capacity to improve feed efficiency by 4% (“Data on Dairy Science”, 2012). Because of the traction and popularity associated with this feed supplement, which improves productivity while also combating a severe public health crisis, there is potential for MSP to be utilized in a similar manner, with the intent to mitigate the impending public health crisis of climate change.

In anticipation of concerns among farmers and other food animal industry leaders that dietary supplementation would be too costly, it is important to emphasize that methane reduction and productivity are not mutually exclusive; in fact, quite the opposite is true. Dietary manipulation, as a means by which to decrease methane emissions, may also have the attractive quality of improving feed efficiency and animal productivity (Lovett et al., 2003). Protein rich, plant-based supplements are capable of improving milk production and composition, daily weight gain, and feed conversion efficiency (Khan et al., 2015). In other words, with the use of dietary supplements, animals can be brought to their goal weight more quickly while producing higher-quality meat. The inclusion of such methane-inhibiting concentrates has been found to correspond directly with more rapid animal development and increased body weight while potentially reducing enteric methane by up to 40% (Benchaar et. al., 2001, Lovett et al., 2003). The investment in dietary supplements may therefore ultimately result in money saved that would otherwise be spent on longer rearing times to get animals to their goal weight. The inclusion of protein-rich plant concentrates also has the potential to not only decrease enteric methane production but also increase the fat content in milk when included in the diets of dairy cows (Tirado-Estrada et. al., 2018). Integration of protein-dense supplements into the diet may be the most feasible option for increasing productivity while decreasing enteric methane production by dairy and beef cattle. For this reason, dietary supplementation of this sort is considered the most appealing and cost-effective option to motivate farmers to adopt more sustainable practices (Patra, 2010).

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Green Weed, Green Planet

Evan 22 Comments

Tyler Clements (Environmental Science), Rudy Marek (Geology), Mitch Maslanka (Natural Resource Conservation), Olivia Santamaria (Horticulture)

In 1996, California voted to become the first state to legalize marijuana for medical use. Fast forward to today, and the legalization of marijuana is now a seemingly unstoppable movement that is sweeping across the United States. With recreational and medicinal use being rapidly legalized all over the country, 29 states have already legalized marijuana medicinally and 9 have recreationally (Robinson, Berk, & Gould, 2018, para. 2). From the start of California legalizing marijuana, this new industry with seemingly endless potential was given the green light to begin at the commercial level. As of 2017, the industry has grown from $6.73 billion to $9.7 billion in North America (Borchardt, 2017, para. 1; Robinson, 2018, para. 6; Zhang, 2017, para. 2). The entrepreneurs of the country began to think of ways to create and expand a marijuana based business and one of the most important aspects of this process was how the marijuana itself was going to be grown. Continue Reading →

Shifting Subsidies From Corn Ethanol to Solar

Evan 25 Comments

Evan Chakrin: Horticulture

Ryan White: Animal science

Tim Miragliuolo: Building and Construction Tech.

 

 

A sun tracking solar panel in a corn field. (http://www.shutterstock.com)

 

 

Nobody likes wasteful government spending on programs that don’t benefit consumers or the environment, but that is exactly what’s happened with decades of corn ethanol subsidies. The American taxpayer is forced to underwrite the production of an inefficient energy source, and forced again to buy its product when used in gasoline mixtures at fuel stations across the country. Gasoline-ethanol mixes cost consumers miles per gallon and clog the fuel systems of seasonal use equipment and recreational vehicles (Regalbuto, 2009; Patzek et al., 2005) and do little to help the environment (Vedenov & Wetzstein, 2008). After having cost US taxpayers over 40 billion dollars from 1978-2012 (Melchior, 2016), federal tax code supports over 26 billion in subsidies for corn ethanol through 2024 (“Federal subsidies”, 2015). It is time to shift federal incentives toward truly renewable energy systems, and solar photovoltaic [PV] technology provides an excellent answer to our future energy needs. Due to the relative land usage, flexibility of installation, and greenhouse gas emission efficiency of PV systems, we believe that all future corn ethanol tax incentives should be redirected toward the installation of photovoltaic solar panel systems either in isolated systems or through collocation with viable biofuels and vegetable crops. Continue Reading →

Monocultures in America: A System That Needs More Diversity

Evan 465 Comments

 

 

Early in the morning after a hot cup of coffee, Jim climbs up onto his tractor, turns the key, and drives to the edge of his vast corn fields. The arms of the spray boom unfold, creating a wingspan of 120 feet. As Jim drives down designated rows, a combination of water and chemicals sprays over his crops coating everything, but killing only pesky weeds (“Crop Sprayer”, n.d.). While most perish under the harsh conditions, a few weeds survive. Application after application, season after season, more weeds survive. Attempting to save his corn yields while still making some profit, Jim increases application rates and dates. However, as time goes on, nothing seems to help. The pesky weeds outsmarted the old farmer, leaving him in despair (“How Pesticide Resistance Develops”, n.d.).

Jim, like thousands of farmers across the country, is experiencing negative aspects of monoculture, or the agricultural practice of growing a singular crop species in which all plants are genetically similar or identical over vast acres of land (“Biodiversity”, n.d.). Despite high yields and relatively low input prices, growing just one species of crop on many acres of land creates major pest problems. Current American agricultural policies covered by the Farm Bill incentivize the overproduction of commodity crops, such as corn, wheat, soybeans and cotton, in monoculture systems. When the Farm Bill originated during the Great Depression, however, its goal was to preserve the diversified farm landscape. At the time, surplus ran high but demand fell low, driving crop prices into the ground. Farmers struggled to make mortgage payments. Fearing that farms would be forced out of business, President Roosevelt passed the Agricultural Adjustment Act, which paid farmers to not cultivate a certain percentage of their land. This successfully reduced supply and increased prices, keeping the market afloat (Masterson, 2011). Following the stabilization of crop prices, the Farm Bill became a permanent piece of legislation in 1938. For the next forty years, farmers continued to grow both staple crops (corn, wheat, and oats) and specialty crops (fruits and vegetables), as well as livestock (Haspel, 2014).

During the latter half of the 20th century, American agriculture experienced an overhaul. The Green Revolution during the 1960s increased crop production through the introduction of synthetic fertilizers, pesticides, high-yielding crop varieties, and farm equipment mechanization (Mills, n.d.). Farm size dramatically increased over time; since the 1980s, the average number of acres per farm increased by over 100% (DePillis, 2013). Farms consolidated, resulting in 20% of farmers producing 80% of agricultural outputs (Mills, n.d.). New practices, combined with new additions to the Farm Bill, changed the way farmers managed risk (Haspel, 2014). One such addition included the Marketing Loan Program, which revolves around a set price agreed upon by Congress. If crop prices fall below a certain point, the U.S. government will reimburse farmers the difference. This reimbursement program encourages farmers to increase production regardless if they need to or not. The more they grow, the more money they make, even if it lowers current market crop prices (Riedl, 2007). In 1996, for example, Congress increased the price point of soybeans from $4.92 to $5.26 a bushel. To capitalize on the situation, farmers planted 8 million more acres of soybeans, dropping soybean market prices 33% (Riedl, 2007). Despite the price drop, farmers actually made more money through the reimbursement program. The Farm Bill promotes overproduction which saturates the market with product and artificially lowers prices.

In addition to overproduction, industrial monoculture predisposes farms to pest problems. To keep up with intensified production, farmers increased pesticide and fertilizer usage, crop density, and the number of crop cycles per season, but decreased crop diversity (Crowder & Jabbour, 2014). Overcrowding genetically uniform plants allows pests to spread through fields with relatively little resistance, compared to a more diverse array of species (“Biodiversity”, n.d.). Perhaps the most infamous account of pests sweeping through a field occurred in Ireland during the 1840s. Irish farmers grew a single variety of potatoes. In 1845, the potato late blight fungus destroyed nearly half of the potato crop, and continued to kill more and more for seven years (“Irish Potato Famine”, 2017). Just like fields during the Irish Potato Famine, modern monocultures risk infestation at any moment.

The inherent issues of pest management in monoculture systems will be exacerbated by the effects of climate change. Increases in average temperature creates a favorable environment that support larger pest populations. All insects are cold-blooded organisms, meaning that their body temperatures and biological processes directly correlate to environmental temperatures (Petzoldt & Seaman, 2006; Bale & Hayward, 2010). The reproductive cycles for pests such as the European corn borer, Colorado potato beetle, and Sycamore lace bug depend on temperature (Petzoldt & Seaman., 2006). Due to higher average temperatures, these reproductive cycles require less time (Petzoldt & Seaman, 2006). For example, the Sycamore lace bug saw drastic time reductions in egg development. At 19?C, Sycamore lace bug eggs required 20 days to fully develop, but at 30?C, eggs reached full maturity in 7.6 days (Ju et al., 2011, p. 4). Warmer average temperatures allow faster reproduction rates of pests, leading to a significant increase in pest populations. As pest populations grow in size, so does the threat to monoculture farming.

Higher average temperatures will not only shorten the reproductive cycles of insects, but will also limit the pest control mechanisms of winter. 2015 was the warmest winter on record, and 2016 was not much cooler. On any given day throughout 2016, states across the country experienced daily temperatures up to 12.1?C warmer than normal (Samenow, 2017, Chart II). As a result of climate change, scientists expect milder winters to continue. The National Weather Service predicts the winter of 2017 will be consistently warmer than usual (Samenow, 2017). Insects lack a method to retain heat, forcing crop pest to develop survival strategies during winter. Insects fall into two categories, freeze-tolerant and freeze-avoiding, both which remain dormant throughout the winter (Bale & Hayward, 2010). Milder winter temperatures will have varying effects on species of crop pest, but overall a 1-5?C increase will decrease thermal stress in both freeze-tolerant and freeze-avoiding insects (Bale & Hayward, 2010). The southwestern corn borer is one species that benefits from milder winters. During summer of 2017, farmers in Arkansas reported higher numbers of southwestern corn borers (SWCB) following the mildest winter recorded in 2016. To combat SWCB, farmers across the state deployed pheromone traps. The traps captured 300% more SWCB moths per week during the 2017 season compared to previous years. (Studebaker, 2017). Mild winters will help crop pests survive through the winter, increasing the potential for crop infestation and damage.

Warmer winters will also drive pest populations northward into uncharted territories of farmland. The United States Department of Agriculture (USDA) classifies similar climatic regions into hardiness zones to help farmers determine which crops will thrive in their area. Over the past thirty years, increasing temperatures associated with climate change have shifted hardiness zones towards the north. For example, the USDA now classifies northwestern Montana as a zone 6a instead of 5b. Crops such as ginger and artichokes can now successfully grow in this region (Shimizu, 2017). Similarly, more pests can thrive in more northern locations. Beetles, moths, and mites are moving towards the poles at a rate of 2.7 kilometers per year (Barford, 2013). Additionally, fungi and weeds are moving north at a rate of 7 kilometers per year (Barford, 2013). As these ranges grow, farmers need to develop new strategies to control pests they have never encountered. Climate change will unleash a myriad of changes in crop pests: their reproduction rate, winter survival rate and ranges all increase as temperatures rise. To adapt to these changes, farmers have many options, each with their limitations.

The most common strategy to combat pests in monoculture productions is to increase pesticide application rates per acre. Theoretically, more pesticides will kill more pests. However, that solution losing practicality due to the more subtle effects of climate change. Pesticides efficacy decreases as the global temperatures rise. Detoxification rates, or the time required to breakdown a pesticide to render it unharmful to weeds, decrease with increasing temperatures (Matzrafi et al., 2016, p. 1223). A 2016 study, for example, determined that climate change negatively affected the effectiveness of two common herbicides, diclofopmethyl and pinoxaden. At low temperatures (22-28?C) diclofopmethyl and pinoxaden prevented the growth of any weeds. However, at high temperatures (28-34?C) 80% of weeds survived diclofopmethyl application and 100% of weeds survived pinoxaden application (Matzrafi et al., 2016, p. 1220, 1223). Applying larger quantities may work initially, but as the overall global temperature continues to rise, pesticides will become less and less effective. Farmers will not be able to afford the quantities needed to control pests.

While current pesticides are losing their ability to kill crop pests, new, more effective pesticides are millions of dollars and years away from development. In 2016, developing a new pesticide required almost 11 years of research and carried a price tag of $287 million dollars. Technological advancements will not be developed fast enough to defend monocultures from the risk of change (“Cost of Crop,” 2016). Consequently, farmers will apply higher quantities of the same pesticide in hopes to control the pest issue. Pesticide cost estimates, under a 2090 climate change model, predict that there is a direct correlation between increasing temperatures and increasing pesticide cost for crops such as corn, cotton, potatoes, and soybeans. In some areas, pesticide usage costs will increase by as much as 23.17% by 2090, aggressively cutting into profit margins (Chen & McCarl, 2001, Table VII).

While farmers attempt to mitigate the negative consequences climate change has on pesticides by increasing usage, further issues arise. Pesticide resistance occurs following repetitious applications of the same pesticide to a field. With each pesticide application, a select few pests survive. They pass on their resistance genes to their offspring, and more individuals survive pesticide application in the subsequent generation. Eventually, the pesticide stops controlling the pest, and crop damage occurs (“How Pesticide Resistance Develops”, n.d.). Currently, there are over 500 reported cases of pesticide resistance and over 250 cases of insecticide resistance worldwide (Gut, Schilder, Isaacs, & McManus, n.d.; “International Survey”, 2017). The most infamous case of pesticide resistance occurs within Roundup Ready crops. Scientists genetically modified crops such as cotton, corn, and soybeans to tolerate glyphosate applications, which is the generic name for the common household weed-killer Roundup. Farmers can spray entire fields with glyphosate and kill everything except the crop itself (Hsaio, 2015). In the United States, 90% of soybeans and 70% of corn grown are Roundup ready crops. The prevalence of Roundup ready crops exposes the drawbacks of monoculture systems. For example, over 10 million acres of farmland in the United States have been afflicted by Roundup resistant pests such as pigweed (Neuman & Pollack, 2010). The increasing rate of Roundup resistance has the potential to dramatically interrupt food security of United States.

As climate change increases the prevalence and range of pests and decreases pesticide efficacy, American farmers will begin to lose their ability to control and maintain its current production levels. Monoculture farms expose themselves to higher risks of pest infestations as well as pesticide resistance. The best strategy for maintaining a stable food supply is to transform American agriculture from monoculture systems to sustainable, diversified farms with a variety of specialty crops. Generally speaking, the more diversified agricultural land is, the more resilient the land is to climate change and other disturbances (Walpole, et. al, 2013). Monoculture fields lack biodiversity, which hinders natural pest control. Unwanted species can spread throughout entire fields with relative ease due to an abundance of their host species and lack of natural predators. In diversified fields, however, pests encounter more resistance when attempting to invade a field; more natural pests and predators, known as biological controls, limit their movement (Brion, 2014).

Diversified farms may already have natural biological controls in their ecosystem, although they can be introduced to farms as well. Biological controls prove to be more cost effective and environmentally conscious than chemical control. Both methods take roughly ten years to develop, but biological controls are much cheaper. In 2004, it cost only two million U.S. dollars to develop a successful biological control, whereas it took $180 million U.S. dollars to develop a successful chemical control. Furthermore, biological control development are 10,000 times more successful than chemical control development, largely in part due to the directed search for biological agents versus the broader search for chemical agents. Most importantly, biological controls exhibit very little to no risk of resistance and harmful side effects, whereas chemical controls have a high risk of resistance and many side effects (Bale, van Lenteren, & Bigler, 2008).

In addition to increasing biodiversity and biological controls, diversified farms use different management practices than monoculture farms. Diversified farms tend to use less synthetic chemical pesticides per unit of production than conventional farms, according to a National Resource Council study (Walpole, et. al, 2013). They also produce more per hectare than large-scale plantations. As stated in a 1992 agricultural census report, diversified farms grew more than twice as much food per acre than large farms by cultivating more crops and more kinds of crops per hectare (Montgomery, 2017).

To mitigate the effects of climate change on American agriculture, the U.S. government must alter its agricultural policies to promote diversified farming. Removing commodity crop subsidies and reallocating that money to farms that practice diversified farming techniques will decrease overproduction in monoculture operations that rely on heavy pesticide usage. Farmers will no longer be able to produce a single crop at maximum volume and continue to make a profit because programs like the Marketing Loan Program will no longer exist. In turn, this will help alleviate pesticide resistance caused by overuse and climate change. Farmers who grow a variety of specialty crops will be rewarded for their environmental stewardship through monetary compensation, similar to how mono-cropping farms used to receive subsidies.

The United States would not be the first country to remove crop subsidies. In 1984, New Zealand removed their crop subsidy program. Like the United States, New Zealand had subsidized as much as 40% of a farmer’s income throughout the 1970s into the early 1980s (Imhoff, 2012, p. 103). Farmers took advantage of government programs similar to the Marketing Loan Program in the U.S. by producing more, therefore receiving more subsidies. During the 1984 election, however, the winning party ran a platform to remove subsidies. The elimination of subsidies from the budget caused no major food shortages like supporters of the U.S. Farm Bill claim would happen. Instead, New Zealand saw an increase in efficiency. For example, the total number of sheep fell following 1984, but weight gain and lambing productivity increased. The dairy industry in New Zealand also saw drastic increases in efficiency, bringing production costs for cattle to the lowest in the world (Imhoff, 2012, p. 104).

In addition to more efficient farms, there is an interesting aspect of subsidy removal brought light to in the New Zealand case. After the 1984 repeal, pesticide usage reduced by 50% (William, 2014). If the United States adopted a similar practice to New Zealand, but instead reallocated commodity crop subsidies towards diversified farming practice, there would be an influx of more efficient and productive farms that could feed the nation while using less pesticides.

Many states have begun to implement grant programs to promote diversified farming. In 2017, Massachusetts granted over $300,000 toward businesses and farms promoting diversification through specialty crop production. In concurrence with the USDA, Boston offered grants for projects aimed at improving Massachusetts specialty crops, which include fruits and vegetables, dried fruits, tree nuts, and horticulture and nursery products. In general, these grants support projects that help increase market opportunities for local farmers and promote sustainable production practices by giving money to diversified farms more funds. Community Involved in Sustainable Agriculture (CISA), for example, received a portion of this grant. With the money, CISA plans to provide financial support to specialty crop farmers in Western Massachusetts. The Sustainable Business Organization also received part of the grant, with which they hope to build relationships between specialty crop farmers and buyers. By removing barriers that prevent farmers and customers from doing business, the Sustainable Business Organization hopes to increase sales of specialty crops across New England (“Baker-Polito,” 2017).The United States federal government often looks upon states to make sure programs work on a smaller before the whole country takes after them on a larger scale. If the United States removes subsidies that encourage monoculture and reallocates that money towards diversifying crops on farms, American farmers could emulate programs like those in Massachusetts.  By doing so, problems associated with pests and climate change will be mitigated.

Facing the adverse effects of monoculture agricultural systems and climate change, farmers and legislature must work together to diversify farms across the United States. The current monoculture overproduces food, leading to an increased use of pesticides, even by the mere increase of agricultural land alone. On top of this, increasing temperatures associated with climate change are threatening American agriculture as well. Warmer temperatures increase pest populations and decrease the efficacy of pesticides. Furthermore, overuse of pesticides is allowing pests to develop pesticide resistance, creating a snowball effect between pests, pesticide usage, and pesticide resistance. In order to preserve food security and mitigate the effects of climate change, the United States must remove commodity crop subsidies and reallocate the funds towards diversified farming practices. Doing so will decrease the need for pesticides while increasing crop yields. The fight against climate change will prove to be a challenging process, but collaboration between farmers and government will help ease the process and create positive change.         

AUTHORS

Julia Anderson – Animal Science and Sustainable Food and Farming
Emily Hespeler – Environmental Science
Steven Zwiren – Building and Construction Technology

REFERENCES

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Say “Neigh” to Feral Horses: How to Control the Overpopulation of an Iconic Species

Evan 18 Comments

 

(©Gail H. Collins/USFWS)

According to Mark Wintch, a farmer in Nevada, “If I put my cows out here they will starve” (Philipps, 2014, para. 3). Farmers play a key role in producing food for all of us to eat. This difficult job of ensuring that there is sufficient land and food for their animals shouldn’t come with any more obstacle, but their job gets even harder with the increasing population of wild horses. Feral horses pose numerous threats to not only United States ecosystems, but also to those using public lands for agricultural purposes.

Although horses impact farmers, it is difficult to manage them because they are considered a charismatic or iconic species in many places including the United States (Bhattacharyya, Slocombe, & Murphy, 2011). A charismatic species is one that humans place a unique value upon in regards to cultural, historical or personal significance, or based on aesthetics.  In places like British Columbia, horses pose similar threats, yet management actions became restricted due to political and cultural values placed on horses due to historical significance (Bhattacharyya et al., 2011).

Even though a majority of American society admires feral horses, wild horses still degrade soil and destroy vegetation cattle farmers use to feed their animals. This problem of limited space and vegetation for cattle will only get worse as horse populations grow. Without proper management, the horse population may near 100,000 wild horses by 2019-2020 (Philipps, 2014, para. 7). Since feral horses share 60-80% of the diet of cows, an increase of horse population will affect a farmer’s life even more (Beever & Brussard, 2000, p. 238). Mark Wintch now needs to import his cattles’ food from elsewhere because he can’t put cattle out on pasture due to destroyed land (Philipps, 2014).  Today, 155 million acres of land gets leased out to cattle farmers, which is nearly 25% of the total 640 million acres of United States public land (Bureau of Land Management [BLM], n.d;Vincent, Hanson & Argueta, 2017).  Feral horses inhabit approximately 34 million acres of grasslands and fields on public land in Montana, Idaho, Nevada, Wyoming, Oregon, Utah, California, Arizona, North Dakota and New Mexico as well the Shackleford, Sable, Assateague, and Cumberland Islands (Bradford, 2014). Farmers can lease public land and increase their contributions to the economy when horses reach a manageable population size.

Feral horses in the United States are causing approximately five million dollars in damage to the United States ecosystems’ vegetation (Pimentel, Lach, Zuniga, & Morrison, 2000, p. 54). Since these animals do not belong to any organization, people or group, they are not contributing to the economy and only inflicting ecological damage. In contrast, farmers who use federal land to graze are required to pay the Forest Service or the Bureau of Land Management for leases and permits to graze.  Feral horses pose an economic threat as they are causing only damage to vegetation found on public lands and contributing nothing.

Horses follow no invisible boundary where one farmer’s land ends and another begins, which is one of the reasons why feral horses negatively impact cattle farmers in the United States. Cattle farmers are forced to sue the government just so that the feral horses get removed from the land that they lease. Farmers are even encouraged to “voluntarily” reduce their herds to half of their original size just so that they can keep up with the damage done by feral horses on grazing land  (Philipps, 2014).

There has been a long history of horses in our country. While interwoven with United States culture, their ecological clash negatively affected the United States’ ecosystem.  Horses were introduced to North America by Spanish explorers in Mexico during the early 1500s and slowly roamed northwards into the American heartland (Kirkpatrick & Fazio, 2010). Horses overpopulated these areas because of the lack of natural predators coupled with an abundant amount of grassland (Bradford, 2014). Currently, the government wonders what’s the best way to combat this overpopulation. Managing these horses needs to become a bigger focal point for federal regulators. For proper management of wild horses, the United States government must classify wild horses as an invasive species. The definition of an invasive species is an organism that causes ecological harm where it isn’t native (National Oceanic and Atmospheric Administration [NOAA], 2017, para. 1). Horses fit this definition as they affect the U.S ecosystem while they originally came from overseas. The federal government does not define horses as an invasive species, but is currently under growing pressure to add horses to the invasive species list. Due to the dwindling wild horse population in the 1970s, wild horses were initially protected by the Horse and Burro Act of 1971, but with added protection the wild horse population exponentially grew and caused dramatic impacts to the United States ecosystem (Committee to Review the Bureau of Land Management Wild Horse and Burro Management Program, 2013, p. 15). These horses are feral and a nuisance to ranchers because of their effects on prairie grasslands, which in turn limits the amount of food for cattle.

(The National Wild Horse and Burro Center at Palomino Valley)

Before the Horse and Burro Act of 1971, there was growing widespread public concern about the wellbeing of horses (Committee to Review the Bureau of Land Management Wild Horse and Burro Management Program, 2013, p. 15). Unlike the current state of feral horses where they are viewed as a nuisance, wild horses used to have a declining population. Horses died due to livestock competition and roundups, where the horses were sold for slaughter (p. 15). The public looked for a way to provide a more stable environment for these creatures. The Wild Horse and Burro Act was established in 1971, giving horses allocated federal lands to roam and graze (National Wild Horse and Burro Program, 1971). The act entails the difficult process of controlling the horse population. Horses have no natural predators and under such circumstance reproduce rapidly (Bradford, 2014). The legislation makes it illegal to harm or kill horses on Federal land (National Wild Horse and Burro Program, 1971, Sec. 8). While the act seemed great at first, it became clear that there was far too many horses for the allotted land. Updated legislation includes the Stewart Provision, a law enacted in Utah that relocates horses to greener pastures to save the ecological integrity of the rangeland (St. George News, 2016). This is a good idea to start, but there are way too many horses for relocation. The number of horses needs to decrease by 32,768 to meet the target for manageable rangelands (Bureau of Land Management [BLM], 2017a, table 1). The government has recognized the issue of feral horses with legislative measures, but more action needs to be taken to effectively reduce their numbers and stop their negative impact on the United States Ecosystem.

United States ecosystems have suffered immensely due to the presence of feral horses over the years. Soil quality is an important and influential factor for successful agriculture.  The overpopulation of feral horses degrades soil quality in different ways. Due to trampling the soil around watering holes or common grazing sites, horses impacted the soil (Davies, Collins, & Boyd, 2014). In an experiment done by Davies, Collins and Boyd (2014), areas used for research were defined by exposure to feral horses; horse exposed or horse excluded. In areas where horses were excluded and not grazing, the soil stability was 1.5 times greater than horse exposed areas (p. 127). In horse excluded areas components of the soil, or soil aggregates, became more resistant to naturally occurring causes of erosion such as rain or wind. In horse exposed areas, the amount of force required to penetrate the soil was 2.5 times greater than in areas not exposed to horses, showing that high concentrations of feral horses compact the soil to a significant level (Davies et al., 2014, p. 127).  Due to the presence of horses, horse included areas are at a higher risk of erosion due to degraded soil quality (Davies et al., 2014). Erosion directly impacts agriculture as it removes the top-soil, the most productive and important part of the “soil profile” for agriculture (Queensland Government, 2016).

Feral horses degrade soil quality and thus inhibit agricultural productivity. With increasing soil compaction due to high densities of feral horses, vegetation is unable to penetrate the soil and grow. This leads to greater areas of bare soil exposure (Zalba & Loydi, 2014).  There is a high correlation between proximity to a horse dung pile and the amount of bare ground exposure likely due to the horses trampling areas where dung piles are found causing vegetation to not grow (Zalba & Loydi, 2014). Additionally, in areas that feral horses had access to, the amount of bare ground exposure was 7 times greater than in horse excluded areas in regards to riparian vegetation (Boyd, Davies & Collins, 2017, p. 413). This signifies that with a high density of feral horses present in an area, less vegetation can grow and thus more exposed soil is seen. Agriculture is affected by the presence of horses because vegetation cannot grow in such compacted and eroded soil.

Along with a markedly lower amount of vegetation, presence of feral horses negatively affects the species diversity of vegetation. Low soil quality and increased bare ground exposure decreases the ability of vegetation to grow which negatively impacts species diversity among vegetation. Plant species diversity was 1.2 times greater in horse excluded areas as opposed to horse included areas (Davies et al., 2014). With less vegetation present to hold the soil together and absorb moisture, the soil becomes more susceptible to water inundation and thus erosion.  Horses have the ability to degrade habitat quality over time by altering the seed stock and lower the carrying capacity of the soil for vegetation (Turner, 2015). The ability of vegetation to grow and the type of vegetation is important for ranchers as cattle require grasslands to graze (Philipps, 2014). The overpopulation of feral horses can significantly impact vegetation growth due to overgrazing and compacting the soil thus taking away resources needed for cattle farming.  

The overpopulation of feral horses negatively impacts United States ecosystems along with cattle farmers. As of March of 2017, there is a population of 59,483 wild horses in the United States which is an 8% increase from 2016. The wild horse population constantly trends upward due poor management techniques (BLM, 2017a). This population size is gravely too high and needs to decline to a manageable population of 26,715 (BLM,  2017a).  If horses get managed properly, then the impact wild horses have on the United States ecosystem will decrease (para. 1).

Horse management practices such as adoption and fertility management were used in the past, but proved unsuccessful in reducing horse populations. In the early 2000s, horses were captured and brought to Bureau of Land Management holding facilities which succeeded in making a 2:1 ratio of horses in the wild to animals removed for adoption (Committee of Bureau of Land Management, 2013, p. 16). From the total population of horses in these facilities, only around 4%, or 2,912 horses, were adopted out (BLM, 2017b; BLM, 2017a). The number of horses adopted is low because most of these horses are labeled as “unadoptable” and strict guidelines prohibit people from adoption. Unadopted horses can’t be sold out for adoption because of uncontrollable or tamable behaviors and age (Columbia Broadcasting System/Associated Press [CBS/AP], 2008, para. 8). In 2008 when there were 32,000 horses in captivity, between 500 and 2,500 horses got labeled as unadoptable (CBS/AP, 2008, para. 6-9). This means that there is approximately 2-8% of the horse population that are unadoptable.  Unadoptable horses or horses waiting to get adopted get brought to long term holding facilities where they are provided proper care, but uses a tremendous amount of government funding (Committee of the Bureau of Land Management, 2013, p. 212).

Although there was success with capturing, there was little success with getting the horses adopted out. In 2012, there were still 45,000 horses in holding facilities which used 60% of the Wild Horse and Burro budget (Committee to Review the Bureau of Land Management Wild Horse and Burro Management Program, 2013, p. 16). This totals close to $40 million dollar per year to maintain these horses (Committee to Review the Bureau of Land Management Wild Horse and Burro Management Program, 2013, p. 301). This would mean allotting around $900 per horse already in captivity per year. If more holding facilities got built to store the approximately 33,000 horses needed to be removed for manageable amount in the wild, it would cost the U.S. nearly $30 million extra. This process would cost nearly $70 million per year.

Not only are adoptions bad for the economy and inefficient, capturing and transporting increases horses stress levels (Independent Technical Research Group, 2015). Stress and proper handling was measured on live horses in Australia using different management techniques. The levels were measured based on human interaction with the horses and the time it took for the management technique to take place per horse. According to studies performed on wild horse populations in Kosciuszko National Park, management practices such as trapping and transport are used to bring wild horses to holding facilities (Independent Technical Research Group, 2015, Figure 1). The study discovered that both capture and transport affected the horses’ behavior, social structure, health, and stress (Independent Technical Research Group, 2015, p. 19-22; p. 33-39). Trapping horses normally takes several hours to perform. Transport to holding facilities can take hours to days with limited food and water for the horses. Also, these horses were never handled by humans which increases the fear and stress of the animals. The stress of capturing and transporting horses to holding facilities and the economic impact of these facilities are reasons why these practices don’t manage horses properly. With a more efficient management strategy, the horse population will decrease which, in turn, will free up land and resources for cattle farmers and ranchers.

Similar to capturing horses for adoption, fertility control is another method used in the past yet unsuccessful in decreasing the population to a manageable size.  The two main contraceptives used are Porcine Zona Pellucida (PZP) and Gonadotropin releasing hormones (GnRH). Both drugs control the estrous cycle in horses manipulating a female horse’s (mare) ability to get pregnant (Committee to Review the Bureau of Land Management Wild Horse and Burro Management Program, 2013). Contraceptives proved unpredictable with repeated use and the difficulty of hand injections (Committee to Review the Bureau of Land Management Wild Horse and Burro Management Program, 2013, Table S-1). Fertility control also takes a while to decrease populations. When using PZP as a fertility control method, it took 6 years of annual injections for the horse population to stabilize and not increase (Fort Collins Science Center, 2017, para. 6). It then took around another 12 years to reduce the population size down from 150 horses to 115 horses (National Park Services, 2013, Figure 1). This horse population decreased by only 37% over the course of 12 years. With the current population of horses in the United States, it would take around 24 years to reduce the current population size to a manageable number. Also, PZP increases the average age of mortality for mares ( National Park Services, 2013, p. 123-124). Mares not treated with PZP contraception only lived to an average of 6.47 years while mares given PZP lived on average 19.94 years.  The decrease in mortality increases the age limits of the horses. Since horses live longer, the fertility control is used for a longer period of times, and the horses still affect the environment.

When trying to reduce the horse population down by around 33,000 horses, it will take a lot of time and money. The vaccine, known as PZP, costs $24 per dose and lasts for one year (Masters, 2017). The lifespan of a typical adult horse given PZP is about 20-25 years (Blocksdorf, 2017), meaning that over a horse’s lifetime birth control would cost approximately $540. Incorporating the number of horses that need to be eradicated, this would bring the total cost of the birth control method close to $18 million over a horse’s lifetime; a staggering statistic that shows fertility control isn’t a sustainable or smart choice.

Not only is fertility contraception expensive to reduce horse population size, but it is also not the best method in terms of efficacy. In order for both PZP and GnRH, horses are captured and given the drug by hand or by using a dart (Committee to Review the Bureau of Land Management Wild Horse and Burro Management Program, 2013). Capturing horses then giving the horse the contraceptive is stressful for the horse. According to Kosciuszko National Park, PZP increases the desire for stallions to stay near mares (Independent Technical Research Group, 2015, p. 64-67). When mares are given PZP they become infertile, but appear receptive to male horses (stallions). This extendeds the workload for stallions during breeding seasons because they spend more time attempting to breed with infertile females. Stallions then put forth more energy to stay with the mares, which causes the stallions to become emaciated. Stallions increased reproductive behaviors by 55% when a mare was given PZP (Independent Technical Research Group, 2015, p. 64).The stallions focus more of their time on breeding than eating food. GnRH has a side effect that encourages mares to eat more vegetation (Ransom et al., 2014). Mares act infertile, allowing for increased energy use to eat more vegetation. With the use of contraceptives, horses will continue to negatively impact public agricultural land due to consuming of vegetation. Since there are so many side effects and issues with fertility control, other methods should be used to manage horse populations.

Wild horse populations are very hard to manage and bring down to a capacity suitable for the United States ecosystems. Methods such as adoptions and fertility attempted in the past reached little success. The best option for horse management is culling. Culling is the systematic killing of animals for management purposes. Culling is cost effective, ethical if done properly, and reduces the horse population rapidly (Galapagos Conservancy, n.d). Across the globe, culling projects have been shown to reduce the population of invasive species.

Culling is a common practice used to combat the negative impacts invasive species place on an ecosystem. For instance, culling eradicated an invasive species of goats on Isabela island in the Galapagos. The goats ate plants that hindered the natural ecosystem of the tortoises (Galapagos Conservancy, n.d). The islands infestation totaled around 100,000 goats. The culling project called the Isabela Project brought the number of goats down to 266 on Isabela island and other small surrounding islands. The project achieved this by getting funding to form a hunting team to eradicate the goat population. Helicopters served their purpose by quickly ridding areas of goat populations. By using helicopters, it took only one year to eliminate all goats from Santiago Island. After all the goats got culled, they were left to decompose (Hirsch, 2013, para. 8). The decomposing goats helped to give nutrients back to the Isabella Islands ecosystem that the goats originally destroyed. This concept of leaving the body of an animal in the environment to restore an ecosystem would work well after horse cull.

The removal of goats on Santiago island cost $8.7 million (Cruz, Carrion, Campbell, Lavoei, & Donlan, 2009, p. 1). Santiago Island had over 79,000 goats killed which meant it cost approximately $110 per goat. This amount of money can be compared to a case study on the cost of culling kangaroos in Australia. The government of Australia conducted culls with kangaroos due to their extremely high numbers (500 million) and consequent overgrazing of the land (Sosnowski, 2013). In 2013 there were 1,504 kangaroos shot at a total cost of $273,000, which averages to $182 per kangaroo (Raggatt, 2013).

The data from the two case studies can help predict the cost of culling horses.  This would translate to a total of $5,963,776, a substantial savings over the $18 million birth control method and $70 million captivity cost. The urgency to cull the horse population is due to the rate at which it is increasing by: doubling in size every 4-5 years (National Horse & Burro Rangeland Management Coalition, 2016). A cull seems harsh, but it’s a feasible option that is the quickest way to revert our rangelands back to their original state.

 

Helicopters used to control the wild goat population on the Isabela islands was the quickest and least stressful way of controlling invasive populations as it allowed for the most rapid means of rounding up and killing the goats (Galapagos Conservancy, n.d). This practice works well with culling large population of horses on rangelands. According to data collected from studies performed at Kosciuszko National Park, aerial shooting was the most humane method of reducing and managing an overpopulation of wild horses (Independent Technical Reference Group, 2015, Table 1). When using aerial shooting, there is no need to capture the horses (Independent Technical Research Group, 2015, p. 11) which decreases the amount of stress on the animals. Aerial shooting involves trained shooters to target horses in smaller groups and deliver instantaneous killing head shots (Independent Technical Research Group, 2015, p. 52-59). The head shots quickly kills the horse and leads to less suffering over time for each individual horse.  Aerial shooting takes an average of 73 seconds to chase and kill the horses (Independent Technical Research Group, 2015, p. 3). Aerial shooting is a quick method of reducing the population size of wild horses in a way that leads to less stress over long periods of time.

Although horses are a beloved and charismatic species to the United States, the wild horses have overpopulated and in turn negatively impact the United States ecosystems.  These animals degrade the soil and the ability of vegetation to growth. These issues negatively affect the lives of cattle farmers that reside in the Western United States. To combat the overpopulation of wild horses, culling initiatives should rapidly, efficiently and ethically decrease the population of horses. A culling initiative is the most effective and feasible means of combating overpopulation of wild horses. Lethal management will drastically decrease the population of wild horses in a short amount of time. Bringing the horse population down to 26,715 by the end of the year will allow the ecosystems to rebound to a more natural state (BLM, 2017a). Cattle farmers and agriculture will recover as the ecosystems bounce back from all of the years of exploitation by the overpopulation of feral horses.

AUTHORS

Lydia Graham – Natural Resources Conservation

Samuel Katten – Pre-Veterinary/Animal Science

Samuel Petithory – Environmental Science

 

REFERENCES

Beever, E. A., Brussard, P. F. (2000). Examining ecological consequences of feral horse grazing using exclosures. Western North American Naturalist, 60, 236-254. Retrieved from https://scholarsarchive.byu.edu/cgi/viewcontent.cgi?referer=https://www.google.com/&httpsredi=1&article=1146&context=wnan

Bhattacharyya, J., Slocombe, S. D., Murphy, S. D. (2011). The “wild” or “feral” distraction: effects of cultural understandings on management controversy over free-ranging horses (equus ferus caballus). Human Ecology, 39, 613-625. Doi: 0.1007/s10745-011-9416-9

Blocksdorf, K. (2017). Ever wonder how long horses live? Retrieved from https://www.thespruce.com/how-long-do-horses-live-1887384

Boyd, C.S., Davies, K.W., & Collins, G.H. (2017). Impacts of feral horse use on herbaceous riparian vegetation within a sagebrush steppe ecosystem. Rangeland Ecology & Management (Elsevier Science), 70(4), 411-417. doi:10.1016/j.rama.2017.02.001

Bradford, A. (2014). Mustangs: Facts About America’s Wild Horses. Retrieved from https://www.livescience.com/27686-mustangs.html

Bureau of Land Management [BLM].  (n.d.). Livestock grazing on public lands. U.S. Department of the Interior. Retrieved from https://www.blm.gov/programs/natural-resources/rangelands-and-grazing/livestock-grazing

Bureau of Land Management [BLM]. (2017a). On-Range population estimates as of March 1, 2017. U.S Department of the Interior. Retrieved from https://www.blm.gov/programs/wild-horse-and-burro/about-the-program/program-data

Bureau of Land Management [BLM]. (2017b). Wild horse and burro adoptions into private care. U.S Department of the Interior.  Retrieved from https://www.blm.gov/programs/wild-horse-and-burro/about-the-program/program-data

Columbia Broadcasting Services/Associated Press [CBS/AP]. (2008). Horse population control may be euthanasia. CBS Interactive INC. Retrieved from https://www.cbsnews.com/news/horse-population-control-may-be-euthanasia/  

Committee to Review the Bureau of Land Management Wild Horse and Burro Management Program. (2013). Using science to improve the BLM wild horse and burro program. National Academies Press, 1-436. Retrieved from: https://www.fs.usda.gov/Internet/FSE_DOCUMENTS/stelprd3796106.pdf

Cruz, F., Carrion, V., Campbell, K., Lavoie, C., & Donlan, C. (2009) Bio-economics of large scale eradication of feral goats from Santiago Island, Galapagos. Journal of Wildlife Management, 73(2), 191-200. Doi: https://doi.org/10.2193/2007-551

Davies, K. W., G. Collins, and C. S. Boyd. (2014). Effects of feral free-roaming horses on semi-arid rangeland ecosystems: an example from the sagebrush steppe. Ecosphere
5(10): 1-14. doi:10.1890/ES14-00171.1

Fort Collins Science Center. (2017). Reducing population growth rates: fertility control in wild horse mares. United States Geological survey. Retrieved from https://www.fort.usgs.gov/wildhorsepopulations/contraception

Galapagos Conservancy (n.d). Project Isabella. Retrieved from https://www.galapagos.org/conservation/conservation/project-areas/ecosystem-restoration/project-isabela/

Hirsch, J. (2013). Exterminating the goats of galapagos. Modern Farmer. Retrieved from https://modernfarmer.com/2013/09/killing-goats-galapagos/

Independent Technical Reference Group. (2015). Assessing the humaneness of wild horse management methods. Office of Environment and Heritage, 1-70. Retrieved from http://www.environment.nsw.gov.au/resources/protectsnowies/knp-sssessing-humaneness-wild-horse-management-methods-2804.pdf

Kirkpatrick, J., & Fazio, P. (2010). Wild Horses as Native North American Wildlife. Retrieved from https://awionline.org/content/wild-horses-native-north-american-wildlife

Masters, B. (2017). Can fertility control keep wild horse herds in check? National Geographic Society. Retrieved from    https://www.nationalgeographic.com/adventure/features/environment/wild-horses-part-three/

National Horse & Burro Rangeland Management Coalition. (2016). Horse and burros: overview. 1-14. Retrieved from http://www.wildhorserange.org/uploads/2/6/0/7/26070410/nhbrmc_combinedfactsheets-may.16.pdf

National Oceanic and Atmospheric Administration [NOAA]. (2010). What is an invasive species? National Department of Commerce. Retrieved from https://oceanservice.noaa.gov/facts/invasive.html

National Park Services. (2013). Assateague island seashore resource management brief. U.S Department of the Interior. 1-2. Retrieved from https://www.nps.gov/asis/planyourvisit/upload/Horse-Brief.pdf

National Wild Horse and Burro Program. (1971). The wild free-roaming horses and burros act of 1971. Bureau of Land Management. Retrieved from https://www.wildhorseandburro.blm.gov/92-195.htm

Philipps, D. (2014). As wild horses overrun the west, ranchers fear land will be gobbled up. New York Times. Retrieved from https://www.nytimes.com/2014/10/01/us/as-wild-horses-overrun-the-west-ranchers-fear-land-will-be-gobbled-up.html

Pimentel, D., Lach, L., Zuniga, R., & Morrison, D. (2000). Environmental and Economic Costs of Nonindigenous Species in the United States. BioScience, 50, 53-65. Doi: https://doi.org/10.1641/0006-3568(2000)050[0053:EAECON]2.3.CO;2

Raggatt, M. (2013). Annual roo cull costs $182 a head. The Canberra Times. Retrieved from http://www.canberratimes.com.au/act-news/annual-roo-cull-costs-182-a-head-20131115-2xmw9.html

Ransom, J. I., Powers, J. G., Garbe, H. M., Oehler, M. W., Nett, T. M., & Baker, D. L. (2014). Behavior of feral horses in response to culling and GnRH immunocontraception. Applied Animal Behavior Science, 157, 81-92. Doi: //doi.org/10.1016/j.applanim.2014.05.002

St. George News. (2016). Rep. Stewart’s provisions for Utah make it into spending bill. Retrieved from https://www.stgeorgeutah.com/news/archive/2016/07/16/rep-stewarts-provisions-for-utah-make-it-into-spending-bill/#.WiQ55rQ-fox

Sosnowski, J. (2013). Overview of laws governing kangaroo culling in Australia. Michigan State University College of Law. Retrieved from https://www.animallaw.info/article/overview-laws-governing-kangaroo-culling-australia-0

Turner, J. W. (2015). Environmental influences on movements and distribution of a wild horse ( equus caballus ) population in western nevada, USA: A 25-year study. Journal of Natural History, 49(39), 2437-2464. doi:10.1080/00222933.2015.1024778

Queensland Government (2016). Impacts of erosion. Retrieved from https://www.qld.gov.au/environment/land/soil/erosion/impacts

Vincent, Carol H., Hanson, Laura A., Argueta, Carla N. (2017). Federal land ownership: overview and data. Congressional Research Service, 1-25. Retrieved from https://fas.org/sgp/crs/misc/R42346.pdf

Zalba, S. M., & Loydi, A. (2014). The influence of feral horses dung piles on surrounding vegetation. Management of Biological Invasions, 5(1), 73-79. doi:10.3391/mbi.2014.5.1.07

Fighting Fire with Fire: Effective Fuel Reduction Treatments Preventing Severe Wildfires

Evan 30 Comments

 

Northern California residents are used to dealing with large-scale wildfires erupting near and within their hometowns. However, this past October saw dozens of extreme wildfires simultaneously sweeping across Napa, Sonoma, and Solano counties (Holthaus, E., 2017). Soon after these eruptions, thousands of people were forced to evacuate their homes, 1,500 structures had been destroyed, and eleven people were reported dead. Governor Jerry Brown promptly declared California in a state of emergency making the National Guard available. After one week, one of these fires named the Tubbs Fire, became California’s most destructive wildfire in history, taking 21 lives and destroying 5,643 structures (The California Department of Forestry and Fire Protection [CALFIRE], 2017). Thousands of wildland firefighters worked day and night attempting to contain this fire, only receiving on average three hours of sleep a night (Westervelt, 2017). Ultimately the wildfires were uncontrollable, subsequently destroying thousands of wineries significantly hitting local economies. California Lt. Gov. Gavin Newsom stated that enormous fires interfacing with high population areas is unfortunately the new norm. Just this year, California fires have burned twice as many acres than 2016, and the average amount burned over the past five years (CALFIRE, 2016).

Contrary to popular belief, low severity and frequent wildfires that occur every 1-25 years are key to perpetuating healthy stands of certain forest types, especially in the western U.S (Pacific Northwest Research Station, 2015). Just one hundred years ago, the Northwestern forests contained many gaps in their canopies, and their understories were not very dense (Hessburg et al, 2005, p. 117).  Low severity fires sculpted these forests by keeping the buildup of vegetation at bay which created breaks in continuous fuel, also known as combustible vegetation (Washington, G.W). Breaks in fuel deter mega fires from spreading across the landscape (Hessburg et al, 2005, p. 132). Fire is imperative to forested ecosystems of the Pacific Northwest because it not only reduces stand density and accumulation of vegetation, but there are many ecological benefits such as nutrient recycling, reproduction, and germination, (Hessburg et al, 2005, p. 118).

Approximately a century ago, the U.S. Forest Service (USFS) began putting these important fires out leading to a plethora of excessively dense stands with continuous, built-up fuels (Stephens et al., 2012., p. 549). The USFS were allotted money from an emergency fund allowing them to fight fires without chewing into their own budget (Houtman et al, 2013, p.A) During this century, the West entered a period of intensive logging where the largest trees were repeatedly cut, and many small trees all filled the gaps left behind simultaneously, cutting system called highgrading (Hessburg et al, 2005, p.120; p. 122). Years of fire suppression plus highgrading has transformed the forested landscapes of the Pacific Northwest to be now overly stocked stands, or groups of trees with uniform characteristics, of similar age (Snyder, M., 2014).

Wildfires in the US have been strongly affected by all aspects of global climate change. Climate change has altered current atmospheric patterns especially average air temperatures significantly impacting fire regimes (Huang et al, 2015, p. 89). Warming means that regions will experience drier than normal conditions conducive to extreme fire outbreaks (Harvey, C., 2017). The amount of moisture in vegetation decreases under warmer conditions because of a decrease in relative humidity, and an increase in evapotranspiration rates, or the process in which water is transferred from the land and foliage to atmosphere through evaporation (Huang et al, 2015, p. 89). Wildfires feed off dry fuels because fuels with lower moisture levels take less time to burn, therefore making wildfire behavior more erratic and unpredictable (Flannigan et al, 2009, p. 492) Studies show that in response to drier climatic conditions, the frequency of large fires in the Northwestern US has increased by 1000% since 1970 (Schoennagel et al, 2017, p. 4538) Warming also increases fire severity in being a sharp increase in the amount of area burned in  future predicted fires. In fact, this year alone has seen approximately a 23% increase of acres burned nationally compared to the average amount from 2006-2016 (National Interagency Fire Center [NIFC], 2017).

Not only do extreme wildfires kill off enormous amounts of trees, they also destroy thousands of homes and structures annually. Since 2011, there has been eleven wildfire outbreaks each causing at least one billion dollars in damages (Center for Climate and Energy Solutions, 2011). This October, over 20,000 citizens were evacuated from Santa Rosa California and the neighboring communities to flee from the devastating flames that destroyed everything in their path (Fuller et al, 2017, October 10). Due to past land use history coupling climate change, management through prescribed burning must be implemented at a fast rate to reduce the accumulation of dry fuels, or this megafire trend will only continue to worsen.

One of the most common means of managing forest fires as mentioned before is through prescribed burning. This is where a section of the forest, typically the understory, is purposely ignited to allow for the reduction of fuel to ultimately decrease the size, severity, and frequency of wildfires. (United States Geological Survey, 1999). This is usually done by small federal or state-level ground crews that are trained to maintain control of the fire. This form of management may not work on all landscapes, however it is a proven method in reducing fuel loads effectively.

On the coast of Southern Alabama, multiple prescribed burns were administered every 2-3 years in a Longleaf Pine dominated forest (Outcalt & Brockway, 2010, p. 1615). After eight years, the resulting forest structure and composition consisted of an open Longleaf Pine dominated overstory with a reduction in a woody understory and increase in an herbaceous layer (Outcalt & Brockway, 2010, p. 1622). This description is an ideal Longleaf Pine ecosystem because the build-up of a woody and dense understory heavily increases severe wildfire risk.

Much of the public is concerned about prescribed burning due to a lack of understanding. Some people fear of the chance prescribed burns might go awry and become impossible to contain. However, during the period of 2002-2006, the USFS could not contain 38 out of 3,640 controlled burns performed, which is a 99% success rate (Deirdre, D & Black, A., 2006). Considering how damaging wildfires can be, the chance of a prescribed burn becoming uncontrollable and destructive is quite negligible.

Due to negative opinions regarding prescribed burning and political constraints, there has not be and is not nearly enough prescribed burning being conducted throughout the U.S., especially on Pacific Northwestern national and state forests. After thirteen years, the USFS did prescribed burning on only 4.7% of Oregon’s 15.7 million acres of national forests and administered an even slimmer 1.4% of Washington’s 9.3 million acres (Brunner, J & Bernton, H., 2015, October 20). When broken down by region, of the 11.7 million acres burned using prescribed burning in 2014, the Southeast burned 8 million acres, 69% of the total amount performed throughout the U.S. When compared with western agencies, they only performed 27% of the total acres burned (Coalition of Prescribed Fire Councils, Inc., 2015).

With the expansive amount of information covering the effectiveness of prescribed burning, the question remains why the West is conducting significantly less prescribed burning than the South. Part of the reason lies in fire being an accepted component of southern culture, in fact many southern laws support prescribed burning being done on private property by private non-commercial practitioners and private contractors (Kobziar et al, 2015, p. 565). There are much stricter laws in some regions of the Pacific Northwest limiting the amount of prescribed burning allowed. For instance, the Clean Air Act requires the EPA to enforce states to mandate certain levels of six common pollutants determined by the National Health-based Ambient Air Quality Standards (Engel K.H., 2013, p. 647). For states implementing significant amounts of prescribed burning, the EPA enforces them to carry out smoke management plans (SMPS) that include ways of minimizing smoke from prescribed burns and topics such as what agency will authorize burn permits (Engel K.H., 2013, p.656).

As mentioned earlier Oregon is conducting more prescribed burning than Washington state; Oregon federal and state agencies burned over 450,000 acres between 2010-2015 while Washington state and forest agencies burned less than 150,000 acres (Banse, T. 2016, February 3). Washington State Senator Linda Evans Parlette told the Northwestern News Network that the answer lies partially in these strict smoke management laws the Washington Department of Natural Resources (DNR) imposes on the agencies and people of Washington. To get a prescribed burning plan approved in the state of Oregon, an agency or forest landowner must submit it to the District of Forestry state forester (Battye et al, 1999, p. 101). In order to get a plan approved in Washington state involved a lot more steps: agencies doing prescribed burns of 100 tons of fuel or more, which an average timber burn exceeds, must submit a permit to the DNR complete with pre-burn data and steps for collecting post-burn data (Battye et al, 1999, p. 141). In addition, the DNR region manager must screen the burn site and review the atmospheric conditions the day before the scheduled burn. Finally, the region manager must provide the final approval the day of the planned burn (Battye et al, 1999, p. 142). A solution to these inflexible smoke management laws that date back to the 90’s is modifying the clauses within each state’s’ SMP to allow for more prescribed burns to occur, especially in the west.

House Bill 2928 is a bill recently passed by Washington State Legislature in March 2016, aiming to make prescribed burning authorization more lenient (House Bill 2928, 2016). In summary, the bill calls for burn plans to be approved 24 hours before the scheduled burn as opposed to the day of. In addition, it reclassifies prescribed burning as “forest resiliency burns” allowing for controlled burns to be conducted on days that regular outdoor fires are prohibited. Finally, the bill states that burn permits can only be revoked by the DNR when the prescribed burn is highly likely to result in heavy air quality violations or other safety issues.

With projected warmer temperatures and less precipitation in the future due to global climate change, wildfires will likely increase in many areas of the country, especially of those in the western United States. However this does not necessarily have to mean that the severity of these wildfires has to increase as significantly as projected. Prescribed burning offers an effective treatment to reduce hazardous fuel loads. Moving towards the future we must increase knowledge of the public and politicians on fire ecology, which is a natural process in many western ecosystems.  We also must pass bills that concentrate around the initiative that fire management, both proactive and active, is needed and will be needed even to a greater extent in the future.  If this does not happen, key funding and initiatives may be lost because costs will only increase with more frequent, high severity wildfires. Fire has always been a part of the Western United States ecology and with the changing climate, precautions must be taken to insure low severity prescribed burns are administered to reduce the likelihood of frequent and severe wildfires looking towards the future.

AUTHORS

Gerald Barnes – Natural Resources Conservation with a Concentration in Wildlife Conservation

Oscar Hanson – Building Construction and Technology

Rebecca Holdowsky – Natural Resources Conservation with a Concentration in Forest Ecology and Conservation

REFERENCES

Banse, T. (2016, February 3). Washington state lawmakers want to fight fire with fire more often. Northwest News Network. Retrieved from http://nwnewsnetwork.org/post/washington-state-lawmakers-want-fight-fire-fire-more-often

Battye, R., Bauer, B., & MacDonald, G. (1999 September).Features of prescribed fire and smoke management rules for Western and Southern states. EC/R Incorporated, 1-156. Retrieved from https://www.wrapair.org//forums/fejf/documents/woodard.pdf

Brunner, J & Bernton, H. (2015, October 20). Fighting fire with fire: State policy hampers use of controlled burns. Seattle Times. Retrieved from https://www.seattletimes.com/seattle-news/environment/fighting-fire-with-fire-state-policy-hampers-use-of-controlled-burns/

The California Department of Forestry and Fire Protection [CALFIRE]. (2017, November 29). Top 20 most destructive california wildfires. Retrieved from http://www.fire.ca.gov/communications/downloads/fact_sheets/Top20_Destruction.pdf

CALFIRE. (2016, September 23). Incident statistics. Retrieved from http://cdfdata.fire.ca.gov/incidents/incidents_stats

Center for Climate and Energy Solutions. (2011). Wildfires and climate change. Retrieved from https://www.c2es.org/content/wildfires-and-climate-change

Coalition of Prescribed Fire Councils, Inc (2015). 2015 NATIONAL PRESCRIBED FIRE USE SURVEY REPORT. Retrieved from http://stateforesters.org/sites/default/files/publication-documents/2015%20Prescribed%20Fire%20Use%20Survey%20Report.pdf

Deirdre, D & Black, A. (2006). Learning from escaped prescribed fires – lessons for high reliability. Retrieved from https://www.fs.fed.us/rm/pubs_other/rmrs_2006_dether_d001.pdf

Engel, K.H. (2013). Perverse incentives: The case of wildfire smoke regulation. Ecology Law Quartely. (40)3, 622-672. Retrieved from http://scholarship.law.berkeley.edu/cgi/viewcontent.cgi?article=2023&context=elq

Ensuring that restrictions on outdoor burning for air quality reasons do not impede measures necessary to ensure forest resilience to catastrophic fires, House Bill 2928. (2016) Retrieved from http://lawfilesext.leg.wa.gov/biennium/2015-16/Pdf/Bill%20Reports/House/2928%20HBR%20AGNR%2016.pdf

Flannigan, M.D., Krawchuk, M.A, de Groot, W.J., Wotton, M.B., & Gowman, L.M. (2009). Implications of changing climate for global wildland fire. International Journal of Wildland Fire, 18(5), 483-507. doi:10.1071/WF0818

Fuller, T., Perez Pena, R., & Bromwich, J.E., (2017, October 10). California fires lay waste to 140,000 acres and rage on. Retrieved from https://www.nytimes.com/2017/10/10/us/california-fires.html?action=click&contentCollection=U.S.&module=RelatedCoverage&region=Marginalia&pgtype=article

Harvey, C. (2017) Here’s what we know about wildfires and climate change. Scientific American. Retrieved from https://www.scientificamerican.com/article/heres-what-we-know-about-wildfires-and-climate-change/

Hessburg, P.F., Agee, J.K., & Franklin, J.F. (2005). Dry forests and wildland fires of the inland Northwest USA: Contrasting the landscape ecology of the pre-settlement and modem eras. Forest Ecology and Management, 211, 117-139. doi: l0.1016/j.foreco.2005.02.0

Holthaus, E. (2017). The firestorm ravaging northern california cities, explained. Retrieved from http://www.motherjones.com/environment/2017/10/the-firestorm-ravaging-northern-california-cities-explained/

Houtman et al (2013). Allowing a wildfire to burn: estimating the effect on future fire suppression costs. International Journal of Wildland Fire. A-L. doi: 10.1071/WF12157

Huang, Y., Wu, S., & Kaplan, J.O (2015). Sensitivity of global wildfire occurrences to various factors in the context of global change. Atmospheric Environment, 121; 86-92; doi: 10.1016/j.atmosenv.2015.06.002

Kobziar, L.N., Goodwin, G., Taylor, Leland., & Watts, A.C. (2015). Perspectives on trends, effectiveness, and impediments to prescribed burning in the Southern U.S. Forests. (6)3, 561-580. doi: 10.3390/f6030561

Outcalt, K.W & Brockway, D.G. (2010). Structure and composition changes following restoration treatments of longleaf pine forests on the Gulf Coastal Plain of Alabama. Forest Ecology and Management, 259, 1615-1623. doi: 10.1016/j.foreco.2010.01.039

Pacific Biodiversity Institute. (2009). Benefits of fire in ecosystems. Retrieved from http://www.pacificbio.org/initiatives/fire/fire_ecology.html

Pacific Northwest Research Station (2015, September 14). Fuel treatments: thinning and prescribed burns. Retrieved from https://www.fs.fed.us/pnw/research/fire/fuel-treatments.shtml

Schoennagel et al, (2017). Adapt to more wildfire in western north american forests as climate changes. Proceedings of the National Academy of Sciences of the United States of America, 114(18), 4582-4590. doi: 10.1073/pnas.1617464114

Stephens et al. (2012). Effects of forest fuel-reduction treatments in the United States. Bioscience, 62, 549-560. Doi: 10.1525/bio.2012.62.6.6

Snyder, M. (2014, July 2). What is a forest stand and why do foresters seem so stuck on them. Retrieved from https://northernwoodlands.org/articles/article/forest-stand

United States Geological Survey. (1999, September 22). USGS studies wildfire ecology in the Western United States. ScienceDaily. Retrieved from www.sciencedaily.com/releases/1999/09/990922050418.htm

Washington, G.W. Fire and fuels management: Fire and fuels management: Definitions, ambiguous terminology and references. Retrieved from https://www.nps.gov/olym/learn/management/upload/fire-wildfire-definitions-2.pdf

Westervelt, E. (2017, October 14). In Northern California, exhausted firefighters push themselves ‘to the limits’. Retrieved from https://www.npr.org/sections/thetwo-way/2017/10/14/557620863/exhausted-firefighters-make-progress-against-northern-california-wildfires?utm_campaign=storyshare&utm_source=facebook.com&utm_medium=social

Micro Irrigation: How to Make Every Drop Count

Evan 18 Comments

 

Mike Wissemann is a tenth generation farmer from Sunderland, MA. His farm, Warner Farm, has been an established source of crops for the surrounding towns since 1718. Mr. Wisseman inherited three hundred years of farming techniques and tricks. He spent his high school years working on the family farm and went on to receive a degree in Plant and Soil Science from the University of Massachusetts Amherst. Mr. Wisseman successfully expanded the farm and his crops from potato/onion crop to a wide variety of fruits and vegetables (Schwarzenbach, 2017). However, no amount of experience or education stopped him from losing tens of thousands of dollars when the Northeast experienced one of its worst droughts in decades (Kaufman, 2016). Farmers all over the Northeast were left scrambling to find enough water for their crops–some were even reduced to bucket brigades to get enough water to their acres of farmland (Shea, 2016).

Despite their best efforts, farmers could not plant their second round of crops. Even generally fertile farm areas such as those by rivers had major problems trying to irrigate (Schwarzenbach, 2017). When your entire livelihood depends on a natural resources (such as water), climate change and increasing drought years are a direct danger to your livelihood.

As climate change continues, droughts like the one experienced by Mr. Wissemann, are going to become more common.  Rising temperatures associated with climate change have impacted approximately 80% of monthly heat records (Coumou, Robinson, & Rahmstorf, 2013). As a rule, as temperature increases, the rate at which an organism produces energy increases as well (Hansen, Smith, & Criddle, 1998). This would be beneficial to productivity, if increased temperatures did not have the additional effect of decreasing the amounts of water available in soil. Think about the application of heat to a pot of water; when the water boils, the water escapes the pot in the form of vapor into the air. The same process holds true when heat is applied to the ground; the water escapes the soil in the form of vapor. This process leaves the soil devoid of water for the plants and leads to drought. The U.S. is a top exporter of agricultural goods and climate change is going to have a significant impact on our agriculture (Joint Economic Committee Democratic Staff, 2012). Between 2000 and 2015, 20-70% of the United States experienced abnormally dry conditions each year (Environmental Protection Agency [EPA], 2016). This does not bode well for the agricultural industry as droughts have an intensely negative impact on crops.

Decreased soil moisture means less water is available for the plants. This both leads to water stress and exacerbates heat stress. Water stress is a variety of plant symptoms that negatively affect plant productivity. It also aggravates heat stress which is when a plant suffers significant tissue damage because of high temperatures or high soil temperatures (Hall, 2017). The same way that humans expect to catch a cold from being overly cold or hungry for too long, plants are more susceptible to disease after being dehydrated and overheated for too long. When leaves of corn are subjected to drought-like conditions, they contained 69% more diseased biomass (Vaughan et al., 2016). When a plant is dehydrated, tiny openings in the leaves close to avoid further loss of water through evaporation. When these openings close, the leaf is incapable of expelling oxygen and taking in carbon dioxide–as if the plant is holding its breath (Osakabe, Osakabe, Shinozaki, & Tran, 2014). Increased heat stress and decreased water availability reduces the plant ability to breathe and thus make food. This results in a weakened plant that is more susceptible to disease (Irmak, 2016; Vaughan et al., 2016).

To get a better sense of the effects of combining heat and water stress, these processes can be related to the human body. Heat stress is similar to running; it elevates your heart rate.  If you run forever without rest, you will pass out, and most likely die without medical attention. Water stress, which is like holding your breath, will also eventually kill you, but can be done for some length of time. When heat stress and water stress occur simultaneously, it is like running a marathon while holding your breath. Such a venture would result in near-immediate loss of consciousness, and death without medical attention. Similarly, a plant under both water and heat stress, sees a drastic decrease in productivity, and eventual death without a change in conditions.

We are exceptionally vulnerable to these effects of climate change on our crops due to our current method of water usage. Current estimates reveal that 70% of freshwater withdrawals go towards irrigation uses (Block, 2017) and a large amount of this water could be conserved. A widely accepted, but inefficient method of irrigation is furrow or gravity irrigation. It accounts for 35% to 42% of irrigation systems in the United States (Subbs, 2016). Compared to a more modern technique known as drip irrigation, it wastes 43.6 % of total water use (Tagar et al., 2012,  p. 792). Furrow irrigation involves planting crops in rows with small trenches running in between them. Water is then flown down the trenches that run alongside the crops (Perlman, 2016). Farmers across the nation use furrow irrigation because there are lower initial investment costs as well as a lower cost for pumping water (Yonts, Eisenhauer, & Varner, 2007). Unfortunately, it also wastes a lot of water. The water is not targeted on the roots and much of it goes to wetting soil around the plant and not the actual root. This is inefficient because the roots are the plant structure that absorb the water (Lamont, Orzolek, Harper, Kime, & Jarrett, 2017). The water that is not on the roots is more likely to be lost as soil evaporation which accounts for over 50% water lost in furrow irrigation (Batchelor, Lovell, & Murata, 1996). Traditional forms of irrigation irrigate the entire field, wasting precious water on soil that will not be in contact with the plant’s roots (Lamont et al., 2017).

Plants need fresh water to survive but, unfortunately, water is a finite resource. Although the water covers 70% of the planet, only 2.5% of it is fresh water. This freshwater is “stored” in places like rivers, lakes, ice, and, perhaps most importantly, in the ground. Surface water seeps down through layers of dirt and rock to recharge groundwater storage areas, more commonly known as aquifers. Aquifers are made up of types of rock particles, such as sand and gravel,  that have enough space between them that the water can happily live. We need freshwater for activities ranging from drinking to manufacturing processes to agricultural irrigation. And about 50% of the freshwater we use for these activities is derived from groundwater (Dimick, 2014).  

The main differing factor between groundwater and surface water as a source of fresh water is the time it takes for these reserves to be recharged. Surface waters, such as lakes, can be replenished with seasonal rains. Groundwater on the other hand can take anywhere from months to tens of thousands of years to build up a reserve because the water has to flow through layers and layers of soil and rock to reach the aquifer. It can also be left untouched for long periods of time as it is not susceptible to the same rules of constant evaporation as surface water.

Agriculture has been using up this resource far faster than it can be replaced. It may take years to build up a water reserve, but it only takes seconds to pump it out. For example, the Ogallala Aquifer, which is located under the Great Plains of the United States, recharges at a rate of less than 1 inch per year (Kromm, 2017). However, over the past decade water has been withdrawn at a rate of approximately 18 inches per year. It is estimated that in the next 50 years, 69% of the Ogallala Aquifer will be gone. This depletion of groundwater resources is happening all over the country from the Colorado River Basin to the California Central Valley to the North China Plain to the Middle East (Dimick, 2014).

We cannot fix climate change, however we can mitigate its effects through effective water usage. Using the method of Micro Irrigation also known as drip irrigation, we can conserve water and mitigate the negative effects of water and heat stress on crops. Micro Irrigation involves using pressurized piping that drips water directly on the roots of the plant. It consists of a mainline distribution, sub-mainline (header), drip lines, filters, pressure regulators, and chemical injectors. Laying down an underground network of pipe which has an opening at the base of each plant. Using a pressurizing system to efficiently deliver water directly to the root system of the plant, which is the part that absorbs water (Lamont et al., 2017).

This decreases the water stress on the plants because it ensures that the plants are receiving enough water. Adequate water leads to healthier and more disease resistant crops (Irmak, 2016; Vaughan et al., 2016).

Not only does this method create better living conditions for the plants, it also conserves an incredible amount of water. This will be especially key as water availability decreases with climate change. Drip irrigation improves efficiency of water on farms by reducing the soil evaporation and drainage losses. In terms of conservation, drip irrigation may require less than half the water needed in a sprinkler irrigation method (Lamont et al., 2017). Since the water is applied directly to the roots, no water is wasted on non-productive areas, resulting in even more water efficiency (Lamont et al., 2017). Drip irrigation was much more efficient than furrow irrigation saving 56.4% of the water in comparison. (Tagar et al., 2012,  p. 792).

However, traditional irrigation wastes water in a way that drip irrigation does not. In terms of the framework of increasing water demand with climate change, agricultural methods that recognize water as a valuable, finite resource need to be implemented.  

Furrow Irrigation is cheaper to install initially, but is far more water and energy inefficient compared to drip irrigation. To install, depending on the type of furrow irrigation and the size of the farm, it will be anywhere from $13 to $70 per acre (Wichelns, Houston, Cone, Zhu, Wilen, 1996). There are more repair costs and maintenance costs for this particular type of irrigation and can be anywhere from $13 to $90 annually per acre (Wilchens et al., 1996). While it is cheaper initially, drip irrigation uses water and energy so much more efficiently, that the long term savings of drip irrigation far outweigh the initial cheapness of the furrow irrigation.

Drip Irrigation costs approximately $500- $1,200 per acre, or potentially more, to install (Simonne et al., 2015). For reference, Louisiana Delta Plantation has over 26,000 acres (Honey Brake Lodge, 2017). An acre is about the size of a football field, which would make that farm the size of 26,000 football fields put together. Even at the lowest cost, converting to Drip Irrigation would cost approximately $13 million for the Louisiana Delta Plantation. Even though the initial investment is hard to grasp in terms of magnitude, eventually the system will pay for itself by maintaining crop yields, even in dry years, and lowering energy and water costs (Stauffer, 2010; Lee Engineering, 2017). How much money will be saved and how many years it will take for the new system to pay for itself is largely dependent on the size of the farm and what kind of crop is being grown, therefore, there are not any specific numbers because of the huge variability of farm types and sizes (Stauffer, 2010). In addition, climate change is very difficult to predict precisely enough for long-term cost analysis, and the type of year-to-year predictions necessary to make those calculations are not presently feasible.

Additionally, the drip method is actually shown to increase crop yields by 22%, which itself is motivation for its implementation (Tagar et al., 2012,  p. 792). California almond farmers have seen their crop yields double as they increased their reliance on the micro irrigation system (Block, 2017). Drip irrigation creates better growing conditions by maintaining the correct moisture conditions favorable for crop growth (Batchelor et al., 1996).

However, if the initial investment cost is offset, micro irrigation will save money in the long run. This method of subsidizing the initial cost has been successful in other situations such as in the case of solar panels. An initial investment cost for switching to solar energy can be anywhere between $10,000 and $50,000 (Maehlum, 2014). It would be reduced by thousands of dollars because of the Federal and state tax credits associated with switching to solar power. Eventually, the solar panels will pay for themselves and even save you money in the long term, much like drip irrigation. Largely dependent on how big the house is, how much power is used, and where the house is located, the payback time for switching can vary, but for an average household with a high regular energy cost would be able to payback the initial investment in as little as 15 years (Maehlum, 2014).

A potential source of funding for this initial cost is the federal government. In a recent publication, the United States Department of Agriculture (USDA) showed that they are willing to fund such advancements in the agricultural industry in the name of invasive species, habitat management, soil erosion, and generalized conservation. Since all these factors contribute to the overall health and wellbeing of a farm, efficient watering is logically a top priority for the government.

These programs fall under The Conservation Reserve Program (CRP) which is a program offered by the USDA Farm Service Agency. The CRP is offered as part of an overall program to address invasive species research, technical assistance, and prevention and control that was set up by the USDA in 2015 (United States Department of Agriculture [USDA], 2015). The CRP specifically is a grant based program where the government is willing to supply money to farmers “for establishment of resource-conserving cover on environmentally sensitive croplands.” (USDA, 2015, p. 4). Among other programs, the Environmental Quality Incentive Program, which gives government aid to farmers who want to use more efficient and conservation friendly tools, and the Conservation Technical Assistance Program, which awards tools for conservation to private, tribal, and non federal lands, show a clear willingness for the government to aid in funding programs geared toward conservation and climate change problems (United States Department of Agriculture, 2015). The method under discussion to more efficiently water our farmland is expensive, but clearly the government is willing and able to encourage and fund conservation of farmlands in whatever way possible, even if that means switching to a more efficient water usage irrigation system.

Currently, despite its ability to conserve water, increase crop yields, and mitigate climate change impacts, the use of micro irrigation is not widespread. This is due in part to its high initial investment cost. With grants from the government to offset the initial costs, the system will eventually save money in the long term. A livelihood for farmers like Mike Wissemann, and food for the public like you, are only going to worsen as temperatures continue to rise. Water efficiency is important now more than ever before.

AUTHORS

Jeremy Brownholtz – Environmental Science

Molly Craft – Natural Resource Conservation

Noah Rak – Building and Construction Technology

Mary Lagunowich – Earth System

 

REFERENCES

Batchelor, C., Lovell, C., & Murata, M. (1996). Simple microirrigation techniques for improving irrigation efficiency on vegetable gardens. Agricultural Water Management,32(1), 37-48. doi:10.1016/s0378-3774(96)01257-7

Block, Ben. (2017). “Efficient” Irrigation Tool May Deplete More Water. Retrieved from http://www.worldwatch.org/node/5942.

Coumou, D., Robinson, A., & Rahmstorf, S. (2013). Global increase in record-breaking monthly-mean temperatures. Climatic Change,118(3-4), 771-782.

Dimick, D. (2014, August 21). If You Think the Water Crisis Can’t Get Worse, Wait Until the Aquifers Are Drained. Retrieved from https://news.nationalgeographic.com/news/2014/08/140819-groundwater-california-drought-aquifers-hidden-crisis/

Environmental Protection Agency [EPA]. (2016). Climate Change Indicators. Retrieved from https://www.epa.gov/climate-indicators/climate-change-indicators-drought

Hall, A. E. (2017). Heat Stress and its Impact. Retrieved from http://www.plantstress.com/Articles/heat_i/heat_i.htm

Hansen, L.D., Smith, B.N., & Criddle, R.S. (1998). Calorimetry of plant metabolism: A means to rapidly increase agricultural biomass production. Pure & Applied Chemistry, 70(3).

Honey Brake Lodge. (2017). Louisiana Delta Plantation: About. Retrieved from https://www.honeybrake.com/la-delta-plantation

Irmak, Suat. (2016) Impacts of extreme heat stress and increased soil temperature on plant growth and development. Retrieved from https://cropwatch.unl.edu/2016/impacts-extreme-heat-stress-and-increased-soil-temperature-plant-growth-and-development.

Joint Economic Committee Democratic Staff [JECDS]. (2012). The economic contribution of America’s farmers and the importance of agricultural exports. Washington, DC: U.S. Congress. Retrieved from https://www.jec.senate.gov/public/_cache/files/266a0bf3-5142-4545-b806-ef9fd78b9c2f/jec-agriculture-report.pdf.

Kaufman, Jill. (2016, August 16). Northeast Farmers Grapple with the Worst Drought in Over A Decade. Retrieved from https://www.npr.org/sections/thesalt/2016/08/30/491942025/northeast-farmers-grapple-with-worst-drought-in-more-than-a-decade.

Kromm, David. (2017). Water Encyclopedia: Science & Issue. Retrieved from http://www.waterencyclopedia.com/Oc-Po/Ogallala-Aquifer.html

Lee Engineering. (2017, July 31). 6 Reasons Why Drip Irrigation Pays For Itself. Retrieved from http://lee-engineering.com/irrigation/6-reasons-drip-irrigation-pays/

Lamont, W. J., Orzolek, M. D., Harper, J. K., Kime, L. F., & Jarrett, A. R. (2017, November 2). Drip Irrigation for Vegetable Production. Retrieved from https://extension.psu.edu/drip-irrigation-for-vegetable-production

Maehlum, M. A. (2014, July 18). How Long to Pay Off my Solar Panels? Retrieved from http://energyinformative.org/long-pay-solar-panels/

Osakabe, Y., Osakabe, K., Shinozaki, K., & Tran, L.-S. P. (2014). Response of plants to water stress. Frontiers in Plant Science, 5(86). http://doi.org/10.3389/fpls.2014.00086

Perlman, U. H. (2016, December 9). Irrigation Water Use: Surface irrigation. Retrieved from https://water.usgs.gov/edu/irfurrow.html

Schwarzenbach, V. (2017). Our Story. Retrieved from http://www.warnerfarm.com/our-story/

Shea, Andrea. (2016, August 6). Severe Drought Hits Majority of Massachusetts. Retrieved from https://www.npr.org/2016/08/06/488969852/severe-drought-hits-majority-of-massachussetts.

Simonne E., Hochmuth R., Breman J., Lamont W., Treadwell D., & Gazula A. (2015, October 29). Drip-irrigation Systems for Small Conventional Vegetable Farms and Organic Vegetable Farms. Retrieved from http://edis.ifas.ufl.edu/hs388

Stauffer, B. (2010). Drip Irrigation. Retrieved from https://www.sswm.info/category/implementation-tools/water-use/hardware/optimisation-water-use-agriculture/drip-irrigation

Tagar, A., Chandio, A., Mari, I.A., & Wagan, B. (2012). Comparative study of drip and furrow irrigation methods at farmer’s field in umarkot. World Academy of Science, Engineering and Technology 69, 788-792. Retreived from https://www.researchgate.net/profile/Farman_Ali_Chandio/publication/259346633_Comparative_Study_of_Drip_and_Furrow_Irrigation_Methods_at_Farmer’s_Field_in_Umarkot/links/00b4952b261f3be0ac000000.pdf

Thomson, A.M., Rosenberg, N.J., Izaurralde, R.C., Brown, R.A., & Benson, V., (2012). Climate change impacts on the conterminous USA: An integrated assessment. Part 3. Dryland production of grain and forage crops. Climatic Change, 69(1), 43-65. doi:10.1007/s10584-005-3612-9

United States Department of Agriculture [USDA]. (2015). U.S. Department of Agriculture (USDA) Grant and Partnership Programs that can Address Invasive Species Research, Technical Assistance, Prevention and Control. Washington DC. Retrieved from https://www.doi.gov/sites/doi.gov/files/uploads/USDA%20Grants%20Workbook%20FY%202016%20FINAL%2016%20Oct%202015.pdf

Vaughan, M,. Huffaker, A., Schmelz, E., Dafoe, N., Christensen, S., McAuslane, H., Alborn, H., Allen, L.H., Teal, P.E.A. (2016) Interactive effects of elevated [CO2] and drought on the maize phytochemical defense response against mycotoxigenic Fusarium verticillioides. PloS One. 11(7). doi: 10.1371/journal.pone.0159270

Wichelns D, Houston L, Cone D, Zhu Q, Wilen J. 1996. Farmers describe irrigation costs, benefits: Labor costs may offset water savings of sprinkler systems. Calif Agr 50(1):11-18. https://doi.org/10.3733/ca.v050n01p11.

Yonts, C., Eisenhauer, E., & Varner, D. (2007, June). Managing Furrow Irrigation Systems. Retrieved from http://extensionpublications.unl.edu/assets/html/g1338/build/g1338.htm#target

How Farming Oysters Impacts the Ocean

Evan 148 Comments

 

Oyster Farmer Chris Whitehead adjusting oyster cages

The district was blindsided by the lawsuit. The National Audubon Society, which is a non-profit organization that aims to fight for the conservation of the environment (“Audubon”, 2016) along with the California Waterfowl Association, sued the Humboldt Bay Harbor, Recreation and Conservation District (Kraft 2017). Humboldt Bay is an important stop for migratory birds to eat and rest on the Pacific Flyway, the path of migration for many birds (Simms, 2017).The Audubon society was outraged by the unjust approval for the expansion of a commercial oyster farm (owned by Coast Seafoods and Co) into the Humboldt Bay Harbor that would hurt Canada geese, Western sandpipers, and other migratory birds (Kraft, 2017). The Audubon society claimed that a faulty environmental report was used by the Conservation District to approve the expansion, and that 200 species of birds, 300 species of invertebrates, and over 100 plant species, including eelgrass, would be affected by this expansion (Kraft, 2017). Why does a decline of a 100 small plant species, like eelgrass, matter? Eelgrass supports a multitude of marine organisms and communities, including but not limited to: crabs, sea turtles, young herring, and other microorganisms through acting as food and shelter. With the expansion of aquaculture as a business, about half of the bay would incorporate wire-like structures (Kraft, 2017). Certain methods to harvest oysters trample eelgrass in the process, which for a species already in extensive decline on the west coast, could have detrimental impacts on the ecosystem as a whole (Kraft, 2017). The spokesperson for the Audubon society, Mike Lynes, points to the fact that with a decline of eelgrass comes a decline of certain birds like the black brant and a decline in certain fish as well (Kraft, 2017). Any decline in a resident species in a habitat will affect the food chain and natural flow of the ecosystem. As if not already expected, the general manager of Coast Seafoods denied that the environmental report was faulty and insisted that the proper measures were taken to evaluate the environmental impact the expansion would have on the Humboldt Bay Harbor (Kraft, 2017). Due to the risk of negative alterations to the seagrass life cycle by oyster aquaculture, the size and number of oyster aquaculture farms must be limited in location and method of farming. Continue Reading →

Slowing the Decline of the Bombus

Evan 16 Comments

North American Bombus Pollinates a Vibrant Flower.

 

Alexander Neuzil, Science and Biochemistry

Chase Balayo, Building Construction Technology

Eli Lagacy, Enviornmental Science

 

When we think of our favorite apple, we typically do not associate the image with a

school-aged child precariously perched among the uppermost branches, balancing a pot of pollen

in one hand, while holding a paintbrush in the other hand to paint each individual bud with

pollen.  We don’t usually envision hundreds of farmers walking blossom to blossom, hand

pollinating each individual flower one at a time, hoping that it bears fruit that can be sold at a

market.  As far-fetched an image this is, it’s the reality that is happening right now in China.

Goulson (2012) provides such an example in an article he published in early 2012.  In his article,

Goulson describes how declines in natural pollinators in southwest China due to excessive

pesticide use, and the destruction of natural pollinator habitats, has led to the farmers, and their

children, being forced to hand pollinate the apple and peach trees that grow in that region.  He

goes on to describe what a market without bees could look like, describing the lack of berries,

apples, peas, beans, melons, and tomatoes all of which depend on pollinators such as bees to

thrive (Goulson, 2012).  Nearly 75 percent of crops that are grown globally for consumption by

humans require the services of pollinators to ensure adequate yields (Potts et al., 2010).

Furthermore, the sheer demand by consumers for these crops has skyrocketed in the last half

century, on average doubling over that time span (Goulson, 2012).  Potts et al. (2010) indicates

that the steady increase of crop cultivation occurred from 1961 onward (Potts et al., 2010).

Meanwhile Goulson (2012) also indicates that a combination of increased caloric intake per

person increased nearly 30 percent, and the doubling of the worldwide human population from

just over three billion in 1961 to just over seven billion in 2011 has produced an added strain to

pollination services, such as the bumble bee, as there are not enough pollinators to go around

(Goulson 2012; US Census Bureau).  These trends coupled with the decline of pollinators due to

the combination of several factors, including pathogens, pesticides, and habitat loss can have

serious negative impacts to commercial production of crops which are necessary for food

diversity and production.  (Grixti, Wong, Cameron, & Favret 2009). Continue Reading →

The dramatic decline in Honeybee populations

Evan 32 Comments

 

Matthew Canning- Natural Resource Conservation

Andrew Koval- Wildlife Conservation

Kendra McNabb- Animal Science

Bees are quite an amazing insect, they pollinate over 80% of all flowering plants including 70 of the top 100 human food crops. One in three bites of food that we eat is derived from plants pollinated by bees (Allen-Wardell et al, 1998). Needless to say, bees are important to the crops we humans consume on a daily basis. Over the past two decades, the decline in bee population has reached a critical point. The United States Environmental Protection Agency (2017) concluded that there is a 30% decrease in hive losses annually within the United States. When introduced to stressors, bees can have adverse reactions, leading to what is known as Colony Collapse Disorder (CCD). This disorder that is plaguing global bee populations causes many of the adult and working bees in a specific hive to die out, leaving the colony unable to nourish and protect offspring. This eventually leads to a full destruction of the entire hive. The most logical reason for this phenomenon is the introduction of specific stressors to the hive and its bees directly (VanEngelsdorp, Evans, Saegerman, Mullin, Haubruge, Nguyen, Brown, 2009). If something isn’t done to manage declines in bee populations we can expect a negative impact agriculturally and ecologically. Allen-Warden et al. (1998) showed insecticides and pesticides’ have adverse effects on bees and other pollinating wildlife. This study also showed a reduction in pollinators caused a decrease in blueberry production. We can expect a similar impact on crops to continue as time goes by and this issue progresses. Estimates of the economic toll of honey bee decline is upwards of $5.7 billion per year (United States Environmental Protection Agency, 2017). It is not out of the question that soon homeowners will have trouble keeping their personal gardens sufficiently pollinated, and forego that simple yet satisfying pastime. Knowledge of bee decline  has been acknowledged for many decades, but research and data behind the reasoning for the global decline are still heavily debated. Continue Reading →