How Farmers Can Help Solve the Climate Crisis

A fermer plows his fields in the morning sun

Climate change is already impacting agriculture in the United States. The annual average temperature in the lower 48 states has increased by 1.2 degrees Fahrenheit over the last couple of decades and by 1.8 degrees Fahrenheit since the beginning of the last century, according to the Fourth U.S. National Climate Assessment. Annual precipitation decreased across most of the southern and western U.S. but increased across most of the northern and eastern U.S. 

Agriculture and greenhouse gas emissions

Agriculture also adds to climate change as the sector is responsible for 10.5 percent of total U.S. greenhouse gases. Methane and nitrous oxide are the two main greenhouse gases emitted by agriculture, with carbon dioxide accounting for about nine percent of agriculture-related greenhouse gases. In 2016, nitrous oxide accounted for 46 percent of total greenhouse gas emissions from agriculture. 

Methane and nitrous oxide have a warming potential far greater than carbon dioxide. Methane has a global warming potential of 25 while nitrous oxide’s global warming potential is 298. What this means is that methane contributes 25 times the impact to global warming that carbon dioxide does, and nitrous oxide contributes 298 times the impact. 

Most of the greenhouse gas emissions from agriculture come from crop and soil management, with crop production accounting for 95 percent of emissions. While nitrous oxide is naturally produced in the soil, human activities can increase it, which include fertilization through the application of manure of other organic materials, retention of crop residues, and cultivation of soils with high organic matter content. Irrigation, draining, tillage practices, and fallowing of land can indirectly affect nitrous oxide emissions. 

Agricultural soils and carbon sequestration

Agriculture can reduce greenhouse gas emissions and also remove carbon dioxide from the atmosphere. Plants and soil sequester carbon. “Soils are the largest terrestrial sink for carbon on the planet,” according to the U.S. Department of Agriculture. Forests and croplands in the U.S. sequester the equivalent of 12 percent of carbon from the energy, transportation, and industrial sector. By using farming practices that encourage carbon sequestration and practices that minimally disturb the soil, farmers can slow or reverse carbon loss from their fields.

One way for farmers to minimally disturb soils is to use conservation tillage, which conserves soil by reducing erosion. It reduces soil disturbance and mitigates the release of carbon from the soil while improving the soil’s carbon sequestration capacity. Combining the use of cover crops with conservation tillage will increase the soil’s capacity to sequester soil. Cover crops include grasses, legumes, and forbs planted before the main crop emerges in either the spring or after the fall harvest. Cover crops add biomass to the soil surface and below the surface and sequester carbon. 

How efficient irrigation and rangeland can reduce emissions

There are other ways that farmers can reduce greenhouse gas emissions. One of those ways is through efficient irrigation management. Groundwater pumping is the biggest use of energy on farms. In California, agricultural irrigation uses enough energy to power 1.5 billion homes, and most of the energy use occurs from May to October when the state’s energy use is the highest. Methods such as drip and micro-sprinkler systems reduce water use. Compared to flood irrigation, those methods can achieve up to 90 percent efficiency compared to 60 to 85 percent with flood irrigation. 

Rangeland has a very good potential for carbon sequestration. More than half of California’s land is rangeland. Grazing land for wild and domesticated animals comprises about 830 million acres in the U.S and rangelands account for about 48 percent of that land. Rangelands hold more than one-third of the world’s terrestrial carbon reserves. The sheer size of rangelands has the potential to sequester vast amounts of carbon. Properly managed rangelands have the capacity to store an estimated 19 million metric tons of carbon annually. 

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Larger U.S. Dairies Could Achieve Net Zero Emissions In Five Years

A dairy cow looking through a fence. Large scale dairy production could reach net zero in five years

Among livestock, cows are the biggest emitters of methane in the U.S. Methane is a greenhouse gas with a warming potential of 80 times that of carbon dioxide. However, there is hope that the U.S. can make big reductions on its greenhouse gas emissions. The U.S. dairy industry reduced its emissions by 18 percent from 2005 to 2015 while emissions from the global dairy industry increased by 18 percent during the same period. 

Analysis from the World Wildlife Fund (WWF) finds that larger American dairies could reduce their net greenhouse gas emissions to zero within the next five years. Investing in dairy farms could yield a possible annual return of $1.9 million or more per farm. If only 10 percent of U.S. dairy production achieved net zero, GHG emissions could be reduced by over 13 million tons. 

“We need to make it easy for Americans to prioritize the planet when putting food on the table—to make all choices more sustainable so the burden isn’t on the consumer,” said Jason Clay, executive director of WWF’s Markets Institute, in a statement. “But we also need to make it feasible for farmers. Through this analysis, we’re showing how, with the right incentives and policies, dairy can get there, and get there quickly. And if it’s possible for dairy, other food sectors—and particularly other animal proteins—won’t be far behind.”

The problem of cow poo and digestion

Although the U.S. dairy industry has reduced emissions, making big reductions depends on dealing with their biggest sources of emissions: enteric fermentation (the cow’s digestive process that produces methane), manure management, feed production, and energy (farm energy use and generation). Manure is the industry’s second-largest source of emissions, but it can be part of the solution to reduce emissions. Using manure as fertilizer reduces the need for commercial fertilizer, whose manufacture is a significant source of emissions. 

Enteric fermentation is responsible for about 35 percent of the emissions produced by the dairy industry. The process refers to how cows, which are ruminants, eat and break down food not fit for humans. The analysis suggests that optimizing a cow’s feed will reduce emissions from enteric fermentation and is a key part of achieving net zero emissions. There is research currently being conducted on feed supplements to reduce methane emissions from enteric fermentation. The analysis cites a Dutch product that reported to reduce methane emissions from enteric fermentation by up to 40 percent. The supplement and others like it are not yet approved for use in the U.S. 

The unconventional path to net zero

The WWF advocates for sequestering some dairy emissions and mentions a development from the Salk Institute that involves using gene-edited seeds for cover crops to be used for sequestration. The analysis acknowledges that the development “is not sufficiently advanced to include in the estimates presented here.” However, it goes on to state that “such technologies have the potential to reduce loss of carbon to the atmosphere and help dairies achieve net zero emissions.” Such technology may or may not pan out, but if it does, it could prove to be a useful tool for U.S. dairies in achieving net zero emissions.

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EPA Defies Court Order to Halt the Use of Dicamba

A Monarch butterfly depends on Milkweed.

President Trump’s administration demonstrated its complete disregard for the environment and human health in a myriad of ways. One of those ways involved disregarding a court order regarding an herbicide called dicamba.

The U.S. Environmental Protection Agency registered two dicamba products and extended the registration for another dicamba product for applications on dicamba-tolerant cotton and soybeans. The decision allows dicamba to be in use from 2021 to 2025. Both products will expire in December 2025 “unless the EPA takes further action to amend the registration,” according to the federal agency’s announcement

The EPA’s decision to register dicamba ignores a court order on June 3, 2020 by the Ninth Circuit Court of Appeals to vacate the use of dicamba. The court cited the EPA’s failure to acknowledge the risks the herbicide poses to the environment and conventional crops. On June 8, the EPA told growers they could continue using dicamba until July 31. 

First registered in 1967, dicamba is a widely used herbicide in the U.S. It is used on crops, pastures, fallow land, turfgrass, and rangeland to kill weeds. The herbicide is also registered for use in residential areas and other non-agricultural sites. Over 1,000 products sold in the U.S. include dicamba. 

“Protecting the pesticide industry has been a top priority of the EPA during the Trump administration,” said Environmental Working Group President Ken Cook. “Millions of acres of crops will continue to be damaged, and the health of farmworkers, children, and all those who live near farms where dicamba is used will be at risk – all in the name of appeasing chemical agriculture.”

Environmental, health effects of dicamba herbicide

The EPA claims it “conducted robust evaluations of the risks to human health and the environment.” Yet its decision to register three forms of dicamba shows it ignored the scientific evidence that the herbicide poses environmental and health threats. One of the environmental problems dicamba causes is pesticide drift. Older versions of dicamba caused pesticide drift so they were typically not used much during warm months when they could kill trees or other crops. In 2016, the EPA approved the registration of new formulations of dicamba that allowed for “over-the-top” applications on dicamba-tolerant cotton and soybean plants. 

Scientists warned that the over-the-top applications would cause damage from drift. Complaints about drift damage have increased in several farm states since the introduction of the new applications. In 2017, the EPA tallied 2,708 official dicamba-related crop injury investigations, with 3.6 million acres of soybeans affected. 

Dicamba is a threat to monarch butterflies. The Center for Biological Diversity found that the timing and the geographical distribution of dicamba use coincide with areas where monarch eggs and caterpillars are found on milkweed. The herbicide degrades milkweed which adult monarchs rely on for nectar. As monarchs travel south for the winter, nectar is their only food source. One percent of the minimum dicamba application rate is enough to reduce the size of milkweed by 50 percent. 

The EPA ignores its own evidence that dicamba presents a risk to human health. A 2016 study by the federal agency found that the biggest health risk from either drinking water or dicamba residue on food is found within children one to two years old. 

There are studies linking dicamba use with cancer and thyroid problems. The most recent study found a higher risk of liver, intrahepatic bile duct cancer, and chronic lymphocytic leukemia. A 2010 study found a strong association between dicamba and cancer among those who applied it, while a 2001 study found an association between dicamba and non-Hodgkin’s Lymphoma. Dicamba is linked to thyroid problems. A 2018 study found a significantly increased risk between dicamba and hypothyroidism. Another study done five years prior found “increased odds” of hypothyroidism and dicamba.

What you can do

While it is highly unlikely the Trump administration will halt the use of dicamba, a new administration takes office in January. Start tweeting to Joe Biden and demand that his administration ban the over-the-top applications of dicamba. 

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Why the EPA Should Listen to Science, Not Pesticide Manufacturers

Pesticide resistance results from PIP crops and EPA deregulation

Ignoring science is a hallmark of the Trump administration. A proposed rule by the U.S. Environmental Protection Agency aims to “streamline the regulation of certain plant-incorporated protectants (PIPs).” In reality, it ignores science and listens to pesticide manufacturers and biotech companies. 

The rule is a response to Trump’s executive order on modernizing the regulatory framework for agricultural biotechnology products. The rule proposes exemptions for certain PIPs under the Federal Insecticide, Fungicide and Rodenticide Act (FIFRA) and the Federal Food, Drug and Cosmetic Act (FFDCA). The EPA determined that PIPs “have no risks of concern to humans or the environment.” The EPA characterized regulations governing PIPs as antiquated regulations that restrict access to the market for biotechnology products.” The hallmark of the Trump administration’s environmental policy is deregulation. 

PIPs are plants engineered to contain pesticides. Scientists create them by taking the gene for a pesticidal protein and introducing the gene into the plant’s genetic material which causes the plant to express the pesticidal protein that kills the pest when it eats the plant. The EPA regulates the protein and genetic material. The EPA registered the first Bacillus thuringiensis (Bt) plant-incorporated protectant in the U.S. in 1995. Corn, cotton, and soy Bt incorporated varieties have been introduced. 

The problems with PIPs

While their purpose is to reduce pesticides, PIPs actually cause the development of pesticide resistance in crop-eating insects. A 2010 study found streams throughout the Midwest contaminated with transgenic materials from corn crop byproducts. Six months after corn harvesting, scientists tested 217 stream sites in Indiana and found that 86 percent of the sites contained maize leaves, cobs, husks, and stalks. In 2011, scientists from Iowa State University documented resistance to a Bt toxin by western corn rootworms. They found the western rootworm’s ability to adapt was strongest in fields where Bt corn was planted for three years in a row. 

A 2013 study found tremendous damage from western corn rootworms in a farm field planted with corn genetically engineered to incorporate with a Bt protein. That particular corn variety has been introduced into almost one-third of the corn planted in the U.S. Another 2013 study found that adding more than one Bt-incorporated trait does not prevent pesticide resistance. Researchers looked at caterpillars resistant to pesticides and discovered that caterpillars resistant to one pesticide survived far better than caterpillars not resistant.

Pesticide Resistance

The EPA’s rule exempts certain PIPs created by cisgenic biotechnological techniques. Cisgenic plants derive from genes from sexually compatible species. The rule makes a distinction between cisgenic and transgenic (where the genes come from any species). Les Touart, PhD, Beyond Pesticides senior science and policy manager, analyzed experiments conducted and concluded that they “confirm that cisgenesis can result in significant unanticipated changes to a plant,” and “show that a trait introduced via a cisgene can result in plants that differ in unanticipated and dramatic ways from their conventionally bred counterparts.” He concluded that the “differences observed would have important implications relevant to health and ecological risk assessments.”

The environmental organization Beyond Pesticides sent a letter to the EPA warning that “the agency’s new pesticide resistance management framework as proposed with only minor changes to existing practices will likely prove unsuccessful in the long run as well.” The organization pointed out that the changes proposed “do not address or impact the biology of pest populations developing resistance, but only the recognition and identification of such resistance.”

What you can do

Do you disagree with the EPA’s proposed rule? Sign the petition urging Congress to listen to science and not pesticide manufacturers and biotech companies. Are you outraged by the Trump administration’s environmental deregulation? Today is election day. Vote.

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