We have just 3 rules for irrigation management in Missouri:

1. Using irrigation scheduling!
2. Have your center pivot tested
3. Use fertigation to apply your late-season N to corn (see Peter Scharf's talk)

1) Irrigation Scheduling Irrigators who use an irrigation scheduling program (like the Arkansas Scheduler or Woodruff charts) make about $30-$35 more per acre than those irrigators who do not schedule. See the data from our annual surveys. Both scheduling tools are free and available on the Internet.

Schedulers versus non-Schedulers, SEMO, 2000-2003 (sample size in parenthesis)
Crop	Irrigators Who Scheduled	Irrigators Who Did NOT Schedule	Gross Return from Scheduling
Corn	180 bu/ac (49)	169 bu/ac (153)	$26.90 bu/ac
Cotton	955 lbs/ac (14)	871 lbs/ac (82)	$54.28 bu/ac
Soybeans	46 bu/ac (22)	42 bu/ac (193)	$18.98 bu/ac

2) Test your center pivot. The MU Delta Center is conducting free pivot tests. This is done by setting out a line of cups every 10 feet, and then letting your pivot cross the line of cans. The figure below is a sample result. You can see if you have spots along your pivot that are not getting enough water, or are putting down too much water (this project funded by DNR).


2004 field day report