In 2013, Iowa enacted the Nutrient Reduction Strategy in response to alarming excesses of nitrates, phosphates, and other pollutants in Iowa’s groundwater. These excess nutrients flow to the Mississippi River and into the Gulf of Mexico where they pool and evolve into a hypoxic “dead zone” impairs marine life and threatening local economies. Iowa’s water quality problem has been magnified by worsening soil conditions caused by poor farming practices that threaten soil productivity and crop yields. In 2014, President Obama enacted the U.S. Agricultural Act of 2014, a bill that regulates and subsidizes farming certain crops. In this “Farm Bill”, §7606 gives states the choice to grow hemp for research or as a new cash crop under a pilot program overseen by a state department of agriculture (Pub.L. 113-79, 2014). As of January 2016, 28 states across the U.S. have allowed their farmers to cultivate and universities to resarch hemp, but Iowa, America’s “agricultural state” is not one of those states. Given hemp’s ability to accumulate pollutants found in water and soil and rejuvenate damaged or otherwise degraded soils, in accordance with the 2014 Farm Bill, Iowa should conduct an environmental impact study on the cultivation of hemp as a cash crop in Iowa.
Of the environmental issues plaguing Iowa poor water quality is the most pressing issue facing the state today. According to the Iowa Policy Project over half of Iowa’s waterways were impaired by nutrient pollution in 2014 (Osterberg and Kline, 2014). The largest contributor to these nutrient excesses in Iowa come from primarily farm nutrient runoff. When those nutrients run into the Gulf of Mexico via the Mississippi River, they pool catalyzing algae growth, which suffocates the aquatic life on which local economies depend to thrive – by 2012 this had already caused over $1 billion in damages (Rabotyagov, et al, 2014; Mills, 2012). Runoff occurs when the fertilizers that gets sprayed on crops do not proper infiltrate the soil and get washed into the Iowa’s watersheds when it rains. Recently, the lack of absorption has become particularly problematic because of soil compaction and short-sighted farming practices.
Soil compaction is a condition that results from heavy farm equipment running over damp soil. When this happens the subsoil beneath the topsoil, which gets tilled, becomes densely compacted preventing root penetration that reduces soil productivity by preventing the flow of moisture, nutrients, and air to a plant’s roots because of the change in the hydrodynamic properties of the soil (Raper and Kirby, 2006, p. 1-4). Without enough organic material available for the crop to grow optimally farmers must spray their crop fields with copious amounts of fertilizers to try to stabilize the crop yield. The excesses of fertilizers wash into Iowas’ watersheds with eroded topsoil and into the Mississippi River with precipitation. This problem is magnified by the monocropping practices employed by Iowan farmers and encouraged through ethanol subsidies (Bartestein, 2010, p. 10; Salam, 2012, para. 5). While soil compaction has been a problem since farmers began using heavy equipment to help increase productivity its persistence as a systemic problem seems to indicate the ineffectiveness of the methods traditionally used to mitigate some of this damage. However, there are other, non-traditional options that show promise in helping reverse this damage. One of these controversial options that can be used is industrial hemp.
Industrial hemp is an agricultural cash crop that is legal to cultivate in 30 of the world’s industrialized nations that has gained a negative reputation throughout the twentieth century because it got lumped in with marijuana during the anti-cannabis propaganda in the 1920s and 30s. What makes hemp particularly useful, in terms of the environment, are its’ qualities as a phytoremediator. Phytoremediation is defined by the Environmental Protection Administration as “… the direct use of living plants for in situ remediation of contaminated soil, sludge, sediments and ground water through contaminant removal, degradation or containment (EPA, 1999, p. vii-viii). In short, phytoremediation is the removal of pollutants from soil and water using live plants. As it applies to Iowa, hemp’s root system is complex enough to trap nutrients in the surface soil before fertilizers get washed into Iowa’s groundwater resources. Hemp’s ability to trap the nutrients in the soil also prevents sediment runoff in which eroded soils carry nutrient pollution into water resources because the root structure stabilizes degraded and eroding soil.
However, hemp’s abilities as a phytoremediator are only part of the equation. The depth and complexity of hemp’s root system explain the plant’s ability to restore the damaged soils that magnify the water pollution problem. Hemp has a thick, fiberous taproot that is known to reach depths as deep as 15 feet (Amaducci, Zatta, Raffini and Venturi, 2008, 227-33). Root depth is important because it gives the plant the ability to aerate and return water-soil inflation rates to normal. That means air, water, and nutrients can be retained in the soil for crops to use instead of contributing to the pollution problem. After the crop is harvested, the root system left behind decomposes, thereby returning and diversifying soil organic material where it has been lost, increasing the soil’s productivity. Root decomposition is also important because hemp has root masses that leave nutrients at, incidentally, the optimal depths for corn and soybeans (Amaducci, Zatta, Raffini and Venturi, 2008, 227-33). This may help explain how and why hemp cultivation in the season preceding either corn or soy has been shown to boost the resulting yields, while reducing the amount of fertilizer needed for cultivation of those crops. Furthermore, hemp reduces the need to use herbicides because the plant develops so quickly that its’ fan leaves block the sunlight necessary for competing plants (Abel, 1976, p.31). Without competition from those other plants the need to use herbicides, which have also been found in Iowa’s water, is reduced, as well.
An environmental impact study examining hemp cultivation’s effect on the environment would be able to determine the effectiveness of the plant’s bioremediation abilities, particularly in rural areas that contribute to the alarming levels of nutrient-water pollution. Iowa would not be the only state to conduct such an environmental impact study on hemp cultivation. In fact, hemp’s phytoremediation abilities have been researched by the United States Department of Agriculture dating back to before the 1930s. More recently, Colorado passed an environmental hemp impact study in 2012 to study the plants abilities to remediate pollutants from Colorado water and provide soil restoration for farmers with decreasingly productive cropland (Lauve, 2012, p.1-2). Conducting an environmental impact study in Iowa through cooperation and coordination between the Iowa Department of Agriculture and Land Stewardship, Department of Natural Resources, farmers who choose to opt-in to participate in the program, and Iowa’s universities is necessary because any other studies will be inaccurate due to their lack of focus on Iowa as the case study. Furthermore, its’ widespread cultivation as a cash crop provides a more rounded understanding of the plant’s bioremediation abilities as it would be used in Iowa.
Due to hemp’s relation to marijuana, also in the Cannabis family, many people have opposed legitimizing cultivation of the crop because of fears for public safety. Without understanding the science behind the two plants this common opposition is understandable. However, whereas marijuana used medically or recreationally has tetrahydrocannabinol (THC), the euphoria causing component to marijuana, as high as 38%, hemp is federally classified as containing 0.3% THC or below (Pub.L. 113-79, 2014). Industrial hemp growing nations have certified seed programs to ensure these low levels remain consistent. With THC levels that low one could to smoke nearly an entire field not feel psychotropic effects. One of the few studies conducted to examine whether industrial hemp is suitable for use as a drug explains that hemp’s low THC content and high cannabidiol (CBD) content are discouraging to individuals seeking to get high. CBD is an antagonist to THC and is found in concentrations of more than eight times higher in hemp than marijuana. High CBD concentrations impede hemp’s use as a drug because, when smoked, even a CBD/THC ratio 2:1 neutralize one another, pharmacokenetically (Grotenhermen and Leson, 2002, p. 2, 26-9). Another common public safety objection is that hemp could be used to camouflage illicit marijuana grows because they are difficult to distinguish. However, as the Grotenhermen and Leson study indicates, marijuana with a 1% THC content is considered poor quality (Grotenhermen and Leson, 2002, p. 29). That means users and growers would find marijuana grown in or around hemp fields as a waste of time, in terms of finding a high-quality medicine or recreational drug.
Moreover, in a Congressional Research Report published in 2015, Renee Johnson, an Agricultural Policy specialist, points out that crosspollination between hemp and marijuana crops result in marijuana containing significantly lower THC and is not competitive enough with the widely available, more potent strains of marijuana used for medicine or recreationally as a drug (Johnson, 2015, p. 1-3). This is causing problems in Oregon for hemp and marijuana producers because the crosspollination is severely inhibiting the development of the plants and end products aiming to be produced by the farmer.
In 2015, the dead zone in the Gulf of Mexico spanned an area the size of the the states of Connecticut and Rhode Island, combined (NOAA, 2015, para. 2). Despite having caused over $1 billion of loss to the coastal economies there has been no effective strategy to remediate nutrient pollution from Iowa’s water supply before it mixes in the Mississippi River. However, if the state of Iowa were to authorize an environmental impact study to test the effectiveness of industrial hemp’s phytoremediation abilities and its effect on the quality of Iowa’s water and soil when planted in rotation as a crop in high pollution areas the state could meaningfully work toward finding a longer-term solution. Industrial hemp can remediate excess of nutrients and other pollutants because of its biological processes that are the foundation of hemp’s phytoremediation abilities. Furthermore, the complexity and depth of the plant’s root system would restore soil quality and improve crop yields. If industrial hemp is a solution to water quality that can also restore compacted or degraded soils and return soil productivity lost over decades of monocropping corn and soybeans, then this added value makes the idea of industrial hemp even more appealing – as people dependent on the land and nature it is imperative we act as the best stewards possible. Despite concerns about hemp and marijuana looking similar or being usable as a drug, science and history invalidate these claims because extremely low levels of THC, and the antagonistic effect of CBD on THC prevent it from being used as a drug. Moreover, crosspollination between hemp and marijuana prevent the plants from fully developing and producing the products for which they are being grown. Further, an environmental impact study would give more time to build awareness and in-state demand for hemp facilities and goods, which will otherwise develop much more slowly. Finally, if there is a solution to a problem, no matter how unorthodox and controversial, when it comes to matters of the environment that is distinctly something on which we as humans depend then we have an ethical obligation to one another to consider and explore it as an option. Without being able to shepherd our life-source to meet our demands as a species we will increasingly find our modern farming practices to be harmful to the livelihoods of coastal Americans and the health of residents within the state of Iowa. But, through the cultivation of hemp a large part of the systemic damage will be mitigated.
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Bartenstein, C. (2010). Federal farm subsidies and agricultural industrialization. p. 10
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Johnson, R. (2015). Hemp as an agricultural commodity. p.1-3. Retrieved from https://www.fas.org/sgp/crs/misc/RL32725.pdf
Lauve, J. (2012). Industrial hemp remediation pilot program. P. 1-2. Retrieved from http://www.leg.state.co.us/clics/clics2012a/commsumm.nsf/b4a3962433b52fa787256e5f00670a71/9de11d2e6d488830872579f20066f1d1/$FILE/120502AttachF.pdf
National Oceanic and Atmospheric Administration. (2015). 2015 Gulf of Mexico dead zone ‘above average’. Para. 2. Retrieved from http://www.noaanews.noaa.gov/stories2015/080415-gulf-of-mexico-dead-zone-above-average.html
Osterberg, D. and Kline, A. (2014). A threat unmet. p. 1-3. Retrieved from http://www.iowapolicyproject.org/2014docs/140717-nutrient.pdf
Pub.L. 113-79. (2014). §7606.
Salam, R. (2012). The monocrop cliff. para. 5. Retrieved from http://www.nationalreview.com/agenda/336499/monocrop-cliff-reihan-salam