Declines in pollinator forage suitability concentrated in the Midwest

About one-third of the world’s food crops depend on pollinators like bees. Managed honeybees in the United States alone provide over $350 million worth of pollination services each year. Pollinators rely on the land to provide forage, the pollen and nectar of flowering plants that pollinators feed on to survive. If forage is inadequate, pollinator health may be poor. ERS developed a forage suitability index (FSI) to examine how broad trends in land use have affected the availability of forage for pollinators. Findings show the national average FSI increased by about 2 percent from 1982 to 2002, due in part to the introduction of USDA’s Conservation Reserve Program (CRP) in 1986. The mix of species farmers agree to plant on CRP land often improves pollinator forage. However, the national average FSI plateaued between 2002 and 2012. The FSI had a greater-than-average decline in North Dakota and South Dakota—the summer foraging grounds for many managed honeybee colonies. Decreases in CRP acreage and increases in soybean acreage, which provide poor forage for pollinators, helped drive this decline. This chart appears in the July 2017 Amber Waves finding, "Declines in Pollinator Forage Suitability Were Concentrated in the Midwest, the Over-Summering Grounds for Many Honeybees."

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