Fig. 1. Geographic distribution and variability of five abiotic environment classes (EC) in the United States for CRM 110 maize in 1952–2002. Number of townships under each variability class indicated in parentheses. Percent Not in Dominant EC: percent of years in which a township classified overall as a given class (e.g., EC = Temperate) fell into a different class (e.g., EC = Temperate Dry, Temperate Humid, High Latitude or Subtropical).