Yield of Corn on Frederick Silt Loam as Affected by Slope and Fertility Treatments 1

Experiments were conducted on a B slope (2.5‐7.5%) and on a C slope (7.5‐15%) in 1963, 1964, and 1965, to measure the response of corn { Zea mays L.) on Frederick silt loam to five levels of N applied with three rates of K. Both grain and silage yields were measured. Combined data for the 3 years showed a grain and silage response to only 67 kg N/ha on the B slope, but 134 kg N/ha was required to attain maximum yields on the C slope. Silage yields were increased by 70 and 140 kg K/ha on the B and C slopes, respectively. Grain yields did not respond to applied K on the B slope, but there was a response to 70 kg K/ha on the C slope. Both grain and silage yields on both slopes were similar the 1st year but higher on the B slope in the other 2 years.