Farmers need fertilizer to raise crops, but those fertilizers often end up in streams and rivers, causing pollution problems that affect wildlife. However, the U.S. Department of Agriculture (USDA) supports simple and profitable fertilizer management practices (soil testing and plant tissue testing) that researchers find reduce nitrogen fertilizer use for corn by a whopping 50 percent, as well as stream buffer practices that intercept nutrients as they leave cropland. The list of environmental problems that benefit from the above two practices include restoring hundreds of listed and proposed aquatic species in certain eastern rivers, restoring sea grasses in coastal estuaries, reducing greenhouse gases, reducing dead zones, protecting drinking water, and more. For wildlife, increased adoption of fertilizer management practices offers a simple remedy which could be targeted to restore aquatic species and estuaries.
A large portion of the threatened and endangered species in the U.S. are aquatic species found primarily in certain, eastern streams and rivers. Sediment is the most pervasive threat, but agricultural nutrients are identified as another major cause of these aquatic species’ decline, especially for mussels.
Wildlife in nearby estuaries also benefit from reducing agricultural nutrients. Sea grasses that covered river bottoms throughout the Chesapeake Bay estuary supported tens of thousands of wintering canvasback ducks and other wildlife. Nutrient pollution, largely from agricultural fertilizers, wiped out all but modest remnants of the Bay’s sea grasses by shading them with algae blooms. The same nutrient driven, massive destruction of sea grass habitat and loss of sea grass dependent wildlife occurs in the Gulf of Mexico. Fortunately, in a few coastal rivers where past programs successfully removed the nutrients, substantial sea grass recovery is underway, so we know that effective nutrient remedies can restore the sea grass communities.
Getting a fourth of corn farmers to adopt fertilizer management practices scored a major victory for past Farm Bill conservation programs, for USDA, and for the university scientists that developed the soil tests and plant tissue tests. Yet, the failure to attract more of the other three fourths of farmers must be regarded as a missed opportunity. USDA’s Environment Quality Incentives Program (EQIP) is a bit stingy, offering only a fixed portion of costs for the above fertilizer management practices, just as it does for other, much less beneficial, conservation practices.
USDA could set a national goal, say for 50% or 60% adoption, and considerably increase incentive payments for soil testing and plant tissue testing to reach that enrollment goal. These tests work by helping farmers know how much nutrient is already in the soil — leftover from last year’s fertilizer, from livestock manure applications to the field, or from crops, like soybeans, that add nitrogen to the soil. No one makes farmers pay attention to the soil or tissue test results. The 50% reduction in fertilizer use happens because farmers know that their crops do not need as much fertilizer, as test results help farmers recognize and take credit for nutrients already in the soil. Cities and industry spent billions of dollars treating waste to reduce nutrients in water. With such easy and sensible fertilizer management practices available, agriculture could make a huge contribution to restoring aquatic species in eastern rivers, as well as restoring sea grass dependent wildlife in eastern estuaries.