A. Using leaf temperature to schedule irrigation. When water transpires through the plant it cools the plant. Research is underway by Drs. Thompson and Sudduth on using infra-red sensors to measure leaf temperature and schedule irrigation based on this.

B. Irrigation Frequency. One of the prime management decisions that an irrigator has is how much water to apply per application. Five application depths ranging from 0.5 inches to 3.0 inches have been tested for four years. The total irrigation amounts were kept similar by applying the smaller amounts more often and the larger amounts less often. Results show that ideal application amounts for sprinklers are:

CROP	SAND	SILT
corn	0.75"	1.25"
cotton	0.75"	1.25"
soybean	1.00"	1.50"

C. TeamUp! is a new Extension program (funded by MO DNR). TeamUp! aims to help irrigators optimize their water and Nitrogen management. TeamUp! has three tenets: 1. Irrigation scheduling (MO irrigators who use scheduling make $30/ac more then those that don't. 2. Test pivots for uniformity (a free MU service) and, 3. use aerial photography to aid in late-season N application with pivots

D. Last Irrigation on Corn & Soybeans. Root depths in SEMO are often shallow do to hard pans and frequent rains. Also, plants' root systems begin to naturally decline once fruit begins to set. For these reasons it is important to keep irrigating late into the season.

2004 Field Day Report