The most consistent and positive yield increases have been reported in our neighboring states of Michigan and Minnesota. Research in both of these states have consistently measured grain yield increases from narrow rows in the 7 to 10 percent range. This would imply that perhaps the best opportunity for economic returns to using narrow corn row spacings is in regions with shorter growing season environments. 1997 Wisconsin and Fond du Lac Results Narrow row corn research results from around Wisconsin are presented in Table 1. At each location, corn was planted in 30 inch rows and either 15 or 20 inch rows.
All trials represent data from replicated field trials.
At all seven Wisconsin locations there was a positive response to narrow row spacings. However, at four of the locations the responses were less than two percent. Across all locations, a 3.4 percent yield increase was measured. These results are somewhat surprising considering the relative large positive responses to narrow corn rows measured in Michigan and Minnesota. However, we must keep in mind that this is only one year's worth of data and other studies have shown variable results from year to year.