Education Saves Golf Course Pesticide Usage

Cameron B. Ventre (Turfgrass Science & Management)

John R. Nestro (Natural Resource Conservation)


On a bright and sunny day in Arlington Virginia nearing the end of August, 30-year-old Navy Lieutenant George Prior heads to the Army Navy Country Club to play a few rounds of golf.  Afterwards he heads home and starts to experience flu-like symptoms and became uncharacteristically irritable for no apparent reason according to his wife Liza. His third day on the golf course he began to feel seriously ill with a rash spreading from his stomach which turned into blisters by the next day.  Doctors aren’t able to diagnose him and they can’t seem to understand why his internal organs are beginning to fail. After two weeks of being in the hospital, Lieutenant George Prior dies of a heart attack, but by that time his wife Liza says he was a “hideously disfigured shell of a man” and “death was a merciful escape.” Continue Reading

Green Grass: An Eco Friendly Label for the Massachusetts Cannabis Industry

Marijuana grow sites can be incredibly large, which increases its already intense energy consumption (Image:

Britnay Beaudry: Environmental Science major

Colin Radon: Horticulture major

Pierce Strumpf: Natural Resource Conservation major

The legalization of  marijuana, which went into effect in Massachusetts on December 15th, 2016 was a triumphant victory for marijuana activists and state government. (Commonwealth of Massachusetts, 2018).  Support for this policy change can be seen in the record setting attendance of events like the Boston Freedom Rally, and Extravaganja (Hilliard & Crimaldi, 2017; Tidwell, 2018). But, while marijuana activists have been celebrating their new freedoms, the Cannabis Control Commission [CCC] has been busy writing draft legislation to regulate the budding marijuana industry (CCC, 2018). Starting July 2018, the CCC will begin reviewing applications of recreational marijuana growers (Hilliard & Crimaldi, 2017, para. 20). Many growers are eager for reform and see this as an opportunity to turn their operations legitimate. But before they can receive the necessary permits, they will be expected to reduce their notoriously high energy demands (Dumcius, 2018) The Massachusetts Executive Office of Energy and Environmental Affairs [EEA] and the CCC have been meticulously developing strict regulations to reduce the carbon footprint of marijuana production(EEA, 2018; CCC 2018)  Some growers fear that the regulations, which includes plans to force led lighting on new growers, will cripple the industry before it even has a chance to take off (Dumcius, 2018). “If the commission’s trying to ensure that Massachusetts is known as a state with poor-quality product and high prices this is a great way to do it” Says Kris Kane president of a cannabis consulting company known as 4Front Ventures (Dumcius, 2018, para. 4). Disagreement over environmental regulations threaten to delay the quickly approaching application process. If Marijuana growers refuse to compromise on the bill, the fate of the marijuana industry could go up in smoke. Continue Reading

Solving Hurricanes With Carbon Tax

Can you look this monster in the eye?

Devin Barros: Natural Resource Conservation

Marco Petrosillo: Turf Grass Science and Management

Kyle Vanderhorst: Environmental Science


The term hurricane is derived from Huracan, the name of a Mayan storm god. Over its lifetime, one of these massive storms can release as much energy as a million Hiroshima nuclear bombs (NS). A tropical storm becomes a category 1 hurricane (or cyclone or typhoon) when winds reach sustained speeds of 120 kilometers per hour (kph). A hurricane becomes category 2 when sustained winds hit 154 kph, category 3 at 179 kph, category 4 at 210 kph, and finally the most devastating variety, category 5, when wind speeds hit 250 kph (NS). As you can tell, the reference to a storm god is no understatement.  Hurricanes have always been violent storms; now they’re causing more damage and killing more people than ever before. Will we sit back and watch as the numbers climb, or will we do something about it? Storm activity has been increasing with the changing climate, especially in the northern hemisphere (Emanuel, K., Sundararajan, R., Williams, J. 2008). Climate change is the reason for the increase of storm surge, wind speeds, and the duration.The increase in the duration of hurricanes, storm surge which is essentially sea level rise, and the increase in wind speeds are the three components that are causing the increase in intensity. Emanuel et al. (2008) use simulation technology to show how climate change will affect storm activity into the future as well, showing that it will continue to increase as long as temperatures continue increasing. As a result of the increase in intensity, coastal communities are at much higher risks than ever of being devastated by hurricanes. An overwhelming majority of environmental scientists conclude that the main driving force for climate change is the human caused emissions of greenhouse gases such as carbon dioxide and methane. The emission of these gases cause temperatures to increase and as a result of temperature increase these components get even stronger. Somewhere between 90% and 100% of climate scientists agree that humans are responsible for climate change, with most studies finding 97% consensus among publishing climate scientists (Cook et al., 2016). The number of lives lost to these storms and the money lost because of restoration efforts will only get higher if we don’t do anything to mitigate the intensity of hurricanes. The ten costliest storms combine to an loss of 320 billion dollars in damage and a loss of 16,596 lives (CNN). Ultimately if we wish to mitigate the power of these storms we need to decrease our greenhouse gas emissions. Continue Reading

Invasive Burmese pythons eat their way through southern Florida: the unexpected effect on our health.

Kaley Fournier (Natural Resources Conservation), Edward Hines (Environmental Science), and Nicholas Stevenson (Animal Science).



Image result for invasive burmese pythons catch


It starts with a headache. Perhaps you develop a fever and become physically ill. You chock it up to the flu and try to let it run its course. What you don’t know; you’ve been infected. Once symptoms start to show, death is expected within 2 to 10 days. Even if you get to a doctor in time to save your life, you will most likely be left with mental and physical disability (Center for Disease Control and Prevention, 2016). Where exactly did you come across such a dangerous virus? Your own backyard. Eastern Equine Encephalitis virus is one of the most severe mosquito-transmitted diseases in the United States with approximately 33% mortality and significant brain damage in most survivors (CDC, 2018). The cause of this EEE scare is something unpredictable. The cause can be traced back to something much larger than a mosquito, Invasive Burmese pythons. This snake has slithered its way through southern Florida, devouring native wildlife in its path. This sharp decrease in wildlife populations has forced a change in the animals in which mosquitoes find their dinner. A change to disease ridden animals. Once mosquitos feast on infected hosts, they too become infected. This leaves us with not only wildlife populations to worry about, but also our own health. Continue Reading

Impacts of Climate Change on Southern New England Lobster Fisheries

Victoria Bouffard, Pre-Veterinary Science

Matt Sullivan, Horticulture

James Sullivan, Fisheries

Southern New England fisherman are still catching lobsters, but not in the way they want to be. They are not being caught in traps or nets, but in the stomachs of their predators. Bart Mansi, a lobster fisherman from Long Island Sound, hears from the local bass fisherman about the baby lobsters they find eaten by their catch. Some of the sea bass they pull in have over 10 baby lobsters in their stomachs. This not an uncommon occurrence,  multiple factors are involved with the scarcity of lobsters in southern New England, and increased predation is just the icing on the cake (Skahill & Mack, 2017). The southern New england lobster population has declined dramatically in the past few decades, while catches in Maine have soared. Harvests in Northern regions like the Gulf of Maine and Georges Bank have seen an increase from 14,600 mt (metric tons) in 1990 to 33,000+ mt in 2009, and from 1,300 mt in 1982 to 2,400 mt in 2007, respectively. While the southern New England region landings in Connecticut, Rhode Island, Massachusetts, and the New York border of Long Island Sound, declined from a peak of 10,000 mt from 1997 to 1999, to a low of less than 3,000 mt from 2003 to 2007 (Howell 2012). This dramatic shift in lobster settlement is due to a combination of factors, the most pressing being climate change. The Atlantic Ocean has increased by 0.23℃ every decade from 1982 to 2006, with temperatures varying by region (Pinsky & Fogarty, 2012). As the ocean temperatures rise, the more southern regions of New England are crossing a temperature threshold in which the water is no longer hospitable to lobsters, causing them to migrate North.

Continue Reading

Green Building Materials and Carbon Taxes on the Building Sector: Reducing Emissions from the Built Environment


Kyle Horn: Building Construction Technology

Augustin Loureiro: Geology

Daniel MacDonald: BDIC, Agricultural Research and Extensions

Eric Vermilya: Environmental Science




For those of us looking to do our part to help achieve the goal of preventing climate change and pollution, the answer starts in our homes. Turning off lights, using a clothesline during the warm months, and taking quick showers to save water and electricity are common ways to reduce our impact on the environment. These activities help to cut down on the operational emissions that a home releases into the atmosphere. Unfortunately, there is not much an average individual can do to reduce the embodied emissions that were released when their home was built. In fact, according a study by the Commonwealth Scientific and Industrial Research Organisation, during the construction process of an average residential home, the materials used have embodied emissions equal to 15 years of operational emissions. During the fabrication process of any given material, embodied emission, which are the total emissions produced throughout the entire life of an object, are released. For building materials, this includes emissions from extraction, manufacturing, and transportation (Milne & Reardon, 2013). For people who are trying to do their part to save the environment, this can be a frustrating fact to learn. The building industry which generates new housing and maintains important infrastructure is a major contributor to the emissions that are changing our environment. In fact, according to the IPCC, the Intergovernmental Panel on Climate Change, the building sector accounts for 6% of global greenhouse gas (GHG) emissions (IPCC, 2014). However, this figure does not take into account the embodied emissions of the building materials that are used by the industry. GHG emissions contribute to ambient GHG concentrations which causes the negative effects of climate change. Fortunately, there are a few ways to reduce emissions of GHG’s such as CO2. The first method, is to use materials that have lower embodied emissions. The second method to reduce CO2 emissions, would be to impose a carbon tax on building materials. A carbon tax would deter people from using materials that have high embodied emissions while also providing a source of revenue. This revenue could be funneled into research and development of alternative low emission building materials and/or put into government subsidies on low emission materials which would provide further incentive for people to use materials that are more environmentally friendly. Continue Reading

Shifting Subsidies From Corn Ethanol to Solar

Evan Chakrin: Horticulture

Ryan White: Animal science

Tim Miragliuolo: Building and Construction Tech.



A sun tracking solar panel in a corn field. (



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



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.         


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


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Hydraulic fracturing: A hope for climate change reduction or a curse?


Since the industrial revolution, a substantial percentage of our society relies on energy sources to carry out daily activities. Though energy can now come from renewable sources (e.g., wind, hydro, solar, etc.), the most common way of obtaining energy is through the burning of fossil fuels (e.g., gasoline, coal, oil, and natural gas) in combustion reactions resulting in the production of carbon dioxide, a powerful heat-trapping greenhouse gas (Ophardt, 2000). Greenhouse gases are needed to keep Earth’s atmosphere’s temperature balanced, but if excess gases accumulate in the atmosphere then it increases the temperature of Earth. Since the industrial revolution, increase in human activities have led to exceedingly large carbon dioxide emissions which is now accumulating in our atmosphere warming the planet rapidly. Models have shown that if steps towards climate change are not taken, the Earth could warm up to 2 degrees Celsius which will negatively affect Earth life to a great extent (IPCC, 2013).

While there are different options to obtain energy sources, some of them have harmful effects to our environment. One of the most popular ways to obtain energy is through the burning of coal. Coal based energy production accounts for more than 48% of domestic energy generation in the United States (Bligen, 2014 p. 893). The coal industry in the United States produced 782.4 million tons of coal in 2016 (EIA, 2017, page vii). From mining, to transportation to electricity generation, coal releases a lot of toxic pollutants into the air, water and land. The detrimental effects of coal use range from water pollution to health risks but the broader problem scientists observe is the impact to climate change due to the substantial carbon dioxide emissions. Coal-fired power plants are responsible for one-third of America’s carbon dioxide emissions-about the same as all transportation sources–cars, SUVs, trucks, buses, planes, ships and trains–combined (EPA, 2017, page ES-11). Coal is an important source of energy but it adds a significant amount of carbon dioxide per unit of heat energy more than the combustion of any other fossil fuel. In fact, coal combustion emits more than twice the climate changing carbon dioxide per unit of energy than natural gas production (EIA, 2017, Table #1).

At one point in their lifetime, the average American has used oil as an energy source, indirectly or directly. In addition to coal, the burning of oil has a large impact on our environment. About 40% of the energy consumed in the United States is supplied by petroleum (Bligen, 2010, p. 893). Since the amount of petroleum used varies depending on economics, politics and technology, estimates of carbon dioxide emissions are difficult to predict with certainty. Nevertheless, data has shown that the amount of carbon dioxide released from burning gasoline and diesel fuel was equal to 30% of total U.S. energy-related carbon dioxide emissions (EIA, 2017). In addition to CO2, oil powered plants can also emit particulates NOx and SO2 which are strong gases with direct impact to public health. The economic impact of emissions from oil combustion to public health, including illnesses, premature mortality, workdays lost and direct costs to the healthcare system is equal to 13 cents per kWh (Machol & Rizk, 2013, p. 76).  

Since energy is essential for modern economic and social development, it is crucial that the energy sector look for processes that reduce the negative impacts to our climate. Due to the increased concern over carbon dioxide emissions, natural gas production has increased over the past decade. Natural gas, a combustible gaseous mixture of methane and other hydrocarbons, is used extensively in residential energy; more than half of American use gas for home heating. Natural gas is seen as more climatically beneficial and energy efficient than coal or oil because its combustion produces more energy per carbon dioxide molecule formed than coal (170%) and oil (140%) (Karion et al., 2013, p. 4393).

Conventional natural gas extraction involves retrieving gas from large pools by using natural pressure from wells to pump the gas to the surface (British Columbia). However, conventional gas reservoirs have been depleting, therefore the industry relies on unconventional methods to extract gas from shale rock formations.  Unlike conventional gas, shale gas remains trapped the original rock that formed from the sedimentary deposition of mud, silt, clay, and organic matter on the floors of shallow seas (UCS). Methods of extracting said gas include horizontal drilling and hydraulic fracturing. Hydraulic fracturing, commonly known as fracking, is a process which is used to create cracks in shale rocks to allow air flow.

The rise of shale gas development can be traced back to the 1840s but the first experiment labeled as hydraulic fracturing occurred by late 1940s. By the 1960s companies such as Pan American Petroleum commercialized these techniques. In 1975, former president Gerald Ford promoted the development of shale oil resources as part of the overall energy plan to reduce foreign energy imports (Manfreda, 2015). The increase cost and climatic disadvantages that the oil and coal industry pose led to the sudden boom in the hydraulic fracturing industry. In 2000 shale gas represented 2% of United States natural gas production. By the end of 2016, it topped 60% (Brown, 2014, page 121; EIA, 2017)

Moreover, hydraulic fracturing also poses advantages to the economy in the United States. On average, the cost of gas extracted using hydraulic fracturing is two to three American dollars per thousand cubic feet of gas. This is 50-66 percent cheaper than production from other energy industries (Sovacool, 2014, page 253). Since conventional gas extractions have become more difficult because of depleting sources, natural gas prices could be 2.5 times higher in 30 years if unconventional gas extractions didn’t exist (Jacoby et al., 2012, p. 46). In addition, shale gas development has been proven to increase employment, revenue and taxes in production areas. Production on the Marcellus Shale brought 4.8 billion US dollars in gross regional product, created 57,000 jobs, and generated $1.7 billion in local, state and federal tax collections (Sovacool, 2014, p. 254). These benefits have prompted the United States to promote hydraulic fracturing as the new standard in the energy industry.

The process of hydraulic fracturing is presented to give a better understanding of how hydraulic fracturing works. The first step in hydraulic fracturing is finding a location with a shale rock formation that will produce natural gas. A shale rock formation is made up of fine grade sedimentary rocks that are are compressed into a clay, the shale that is used in fracking is black shale that is rich in organic matter. The  organic matter will undergo heat and pressure and some of it will transform into natural gas. Once the location is found the drilling begins. The drilling is broken into two parts the vertical drilling and the horizontal drilling. The workers first have to drill vertically to a depth around 1,000 feet underground when this is finished a steel casing is inserted into the well so the risk of pollutants won’t spread through the earth’s bedrock and won’t affect groundwater. After the vertical drilling is complete, the horizontal drilling extends out to about 1.5 kilometers through the shale rock formation. After the drilling of the well is completed a specialize performing gunshot is shot which in return creates small holes in the shale formation completing the drilling part of the well (Nacamulli, 2017).

Contrary to popular belief, hydraulic fracturing is not the process of drilling but rather a method used to extract gas after a hole is completed. It is a process that involves injecting water, sand and chemicals at a high pressure into a tight rock formation via a well to stimulate and boost gas flow (Schneising et al., 2014). The propellant in the liquid then goes into the small fractures which keeps them open and allows either the gas or oil to escape from the earth and go up the well and be collected (Schneising et al., 2014). After a well is drilled liquids, such as water and acid, and sand are pumped down the well at high pressures to crack rocks and stimulate shale gas flow. After the shale rock is cracked, the liquid is pumped back to the surface to retrieve the natural gas, this process is known as flowback (Allen et al. 2013). After natural gas is retrieved, the fracking liquid is either pumped back into a separate well and then the well is closed; transported to a water treatment facility or re-used for the stimulation of another well. Recycling the same chemicals with fluid used in new operations contaminates the fluid and creates a more harmful emission the next time around (Nacamulli, 2017). The last step of hydraulic fracturing is the abandonment and plugging of the well. This is done by plugging the well with cement.  

While natural gas does decrease carbon dioxide when used as fuel, there is a concern that the process of fracking leads to massive methane escapes, which is concerning since methane is a potent greenhouse gas (GHG). GHGs are gases that trap heat in the atmosphere. GHGs from human activities are the most significant driver of observed climate change since the mid-20th century (IPCC, 2013). The problem lies in the concentration of greenhouse gases in our atmosphere; if too much is in our atmosphere, then more heat is trapped which leads to the planet warming at an unbalanced state. Models have shown that if society doesn’t take the necessary precautions to reduce greenhouse gas emissions, the Earth could warm up by 2 degrees Celsius which substantially impact Earth life as we know it (IPCC, 2013).

As mentioned before, methane is potent strong greenhouse gas with severe environmental impacts; it has a global warming potential (GWP) of 34 (IPCC, 2013). GWP for a gas is a measure of the total energy a gas absorbs over a particular time period compared to carbon dioxide. The larger the GWP, the more warming the gas causes. Methane has a GWP of 34 meaning that it will cause more warming than carbon dioxide. Methane, however, has a shorter life-time in the atmosphere compared to carbon dioxide. Atmospheric lifetime refers to the amount of time a gas stays in the atmosphere before it is released into space. Methane stays in the atmosphere for a decade, carbon dioxide however is more difficult to measure because there is a myriad of biological processes that remove carbon dioxide from the atmosphere therefore carbon dioxide can actually stay in the atmosphere for thousands of years. Carbon dioxide is the focus on climate change reform because of its long atmospheric lifetime but some scientists claim that there is no way to reduce carbon dioxide emissions in time. Even with major carbon dioxide reductions, Howarth argues that the planet could reach 1.5 degrees in 12 years and 2 degrees in 35 years (as cited in Maggill, 2016). Since the planet responds much more rapidly to methane, a reduction in methane emissions could potentially slow global warming. In order for hydraulic fracturing to provide a net climatic benefit, methane emissions must be lower than 3.2% (Alvarez, Pacala, Winebrake, Chameides, and Hamburg, 2012, page 6437.  However, studies have shown that methane emissions from operating shale gas formations emit higher percentages of methane than 3.2% (Alvarez et al., 2012; Caulton et al., 2014 ; Karion et al., 2013; Schneising et al., 2014). Methane emissions will continue to increase as fracking grows in popularity therefore reform in technologies need to be made in order to create cost and climatic benefits in energy production.

While fugitive methane leakages at fracturing sites are a recognized concern for climate change, methane emissions and leakage are challenges because they occur at various locations during gas extraction and processing. During flowback, we experience the largest amount of  methane emissions are exhibited. As the fracking liquid comes back to the surface, it brings methane released from the shale. During the flowback period, as much as 3.2% of the total natural gas extracted is emitted into the atmosphere (Howarth, Santoro & Ingraffea, 2011 , p. 681). The methane is either captured by emission control devices or emitted into the atmosphere (Allen et al. 2013). Research has shown that methane emissions from shale gas development might be a result of drilling through coal beds which are known to release large amounts of methane. Popular fracking sites, such as the Marcellus Shale formation, are located over coal beds. Another way methane can leak into the atmosphere is through the transportation of natural gas. As natural gas is transported from the well to the storage containers methane leaks through equipment, typically wells have 55 to 150 connections to equipment and make up nearly 90% of methane emission from heaters, meters dehydrators, compressors and vapor-recovery apparatus. (Howarth et al., 2011, Pg. 683) Researchers observed this by examining the unaccounted gas, which is measured by comparing the volume of gas at the wellhead and the amount of gas that was purchased. The estimate of leakage during this time is estimated at 2.5% of emissions (Howarth et al., 2011 Pg. 684-685). Even though it is difficult to trace methane leakage from hydraulic fracturing to just one stage, all of these leaks could be reduced by improving the equipment used. Research performed has shown that the cement used to prevent leaks from well equipments into the atmosphere fails due to installation and material problems (Ingraffea, Wells, Santoro, & Shonkoff, 2014). Since methane emissions from hydraulic fracturing need to be lower than 3.2%, it is crucial that the industry implement reforms to innovate fracking equipment.

Fortunately, methane leaks from fracking are not impossible to stop, and some states have already implemented stricter regulations in order to minimize them. In 2014 Colorado became the first state in the country to place limits on methane emissions from oil and gas operations (Ogburn et al., 2014). Most methane that is lost from fracking comes from leaks in the well infrastructure as well as leaks in the transportation process. In an effort to reduce methane emissions from fracking, Colorado adopted rules which required operators detect and fix leaks and install devices to capture 95 percent of methane emissions (Marmaduke, 2016). It was believed that nearly every step of the methane harvesting process resulted in some amount of methane leakage. In 2016 the Environmental Protection Agency (EPA) passed a rule that was based off of the rule that Colorado had already passed two years earlier. The EPA estimates that theses rules will cut methane emissions by 510,000 tons by the year 2025, which is equal to the amount of greenhouse gases generated by 11 coal fired power plants (Marmaduke, 2016). In the state of Colorado alone, the chief of health estimated that the new rules could cut overall air pollution by 92,000 tons, which is the equivalent of taking every car in the state of Colorado off the road for an entire year (Kroh, 2013). Colorado made significant changes to their emissions standards by requiring all fracking companies to install maximum achievable control technology (MACT). MACT is a set of standards set by the EPA for over 100 categories of different sources of air pollution (West Virginia, 2014). This means that for each of the sources of the pollution the EPA has observed they have set a standard for that source that the company needs to meet. In most cases these standards involve having to install new equipment and machinery that allows less leaks (West Virginia, 2014). In order to install the MACT technology, oil and gas companies will need to be prepared to devote serious financial resources to making it happen. Implementing MACT would force companies to upgrade technology by installing pollution controls, including activated carbon injection, scrubbers or dry sorbent injection, and upgrade particulate controls (Bipartisan, 2013).

The cost of implementing MACT will be high but the costs of climate change are even higher. The cost to implement the technology to meet these standards would be roughly 10.9 billion dollars per year for energy companies that are forced to comply (Bipartisan, 2013). This money would be made up by increasing utility for all customers of companies affected. The EPA estimates that rule would result in an electricity price increase of 3.7 percent and natural gas prices would increase by an average of 0.6 to 1.3 percent (Bipartisan, 2013). This would mean the average natural gas customer would see their yearly bill increase by between $5.95 and $12.90 and the average yearly electrical bill would increase by $49.98 (EIA 2016; Shannon, 2016). By increasing the prices of their customers the companies would be left with a small fraction of the actual cost of the technology and would therefore not have to take on such a financial burden.

The information provided has given use concrete examples and facts about the amount of pollution that’s being emitted into the earth’s atmosphere from fracking. We need to understand   that we need to find a way to make natural gas the great clean energy source that is wanted by many people. Some methane emissions are essential to regulate because of their threat to climate change now and in the future, as we look more for the use of natural gas energy. By understanding the negative impacts of the extraction of natural gas is very important to know how we need to fix the problem of fracking to make fracking clean er and less pollutant. Overall we need to take some emissions present and reduce them to produce natural gas the green energy that is supposed to be. We have seen significant improvements in Colorado act to clean up the methane emissions from fracking.


Andrea Vázquez – Animal Science

Noah Marchand – Environmental Science

Shawn MacDonald – Geology



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


(©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.


Lydia Graham – Natural Resources Conservation

Samuel Katten – Pre-Veterinary/Animal Science

Samuel Petithory – Environmental Science



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