The relationship between insecticide seed treatments and greater sandhill crane (Grus canadensis tabida) crop damage in field and sweet corn (Zea mays)

The role of land-grant university Extension specialist originates in a community of place, enters into communities of interest to leverage resources or partnership opportunities, and returns to the local level with more effective outcomes than possible by operating solely within the community of place. Greater sandhill cranes, Grus canadensis tabida, eat newly planted corn seeds and young plants. Damage can be costly, requiring farmers to replant entire fields in affected areas. Because crane habitat includes a mix of public lands and private farm fields this creates potential for conflict between agriculture and wildlife preservation interests. Historically, this conflict was kept largely at bay by a coincidental relationship between the organochlorine insecticide lindane, and sandhill cranes. Until 2006, lindane was used by farmers as a corn seed treatment for soil insect pests. Farmer observation, and avian dietary studies, found that birds are repelled by lindane treated seed. Since 1996, reduced risk insecticide seed treatments with lower mammalian toxicity have become the norm for soil insect pests of corn. However, these products do not have a repellent effect on cranes. Work conducted with the International Crane Foundation, USDA IR-4, and WI Department of Agriculture resulted in a U.S. EPA special registration for 9,10-anthraquinone on field and sweet corn as a seed treatment to protect against Sandhill crane depredation. Outcomes from this biopesticide project reinforce the concept that Extension specialists are most effective when they forge seamless relationships between communities of place and interest, as ‘honest broker’, to solve unique practical local problems.