Yield Response of Intensively Managed Corn and Soybean to Potassium Fertilizer Rate and Placement

IPNI-2001-CAN-ON24

01 May 2002

2001 Annual Interpretive Summary

Spatial/Temporal Yield Response of Intensively Managed Corn and Soybean to Variations in Potassium Fertilizer Rate and Placement, 2001

Intensive management is designed to narrow the gap between potential and current yields of corn and soybeans. This can also be termed “ecological intensification”, aiming to increase yields and input use efficiency simultaneously. The goal of this project is to examine the variation across a field landscape in corn and soybean yield response to input intensity. The objectives will be to identify parts of the landscape most responsive to increased input levels and to determine the particular constraints to crop growth at these locations during various stages of development.

Seven strips of high-input treatments, comparing normal and high rates of potassium (K) across normal and deep placement and normal and high inputs of nitrogen (N), phosphorus (P), and plant density were initiated in the fall of 2001 across the full length of a large field in preparation for corn and soybeans. Within each of these strips, six zones will be selected for each crop and monitored intensively during the 2002 growing season. Measurements at each zone will include crop phenology, leaf area index, crop biomass at several growth stages, complete characterization of soil fertility, and regular monitoring of soil temperature and water. Complete daily weather data will be monitored for use in modeling crop responses to management systems. ON-24F