Crop ET Weekly Report
The ETgage I check outside of Geneva changed 2.0 inches for the week of June 9-15th. Corn in the V-8 stage has a coefficient of .51”. To calculate how much water, corn at V-8 stage used you simply multiply .51” x 2.0” for a weekly use of 1.02” or .15 inches/day. Corn at V-10 would have used 1.38”/week or .20” per day. We were very fortunate to receive rainfall. The field south of Geneva received 2.3 inches of rain as I write this; at my house we received 3.4 inches.
I did not estimate the crop use for soybeans, since for our area; we typically don’t recommend irrigating them until they reach R3 stage. Watering too early causes taller beans that use more water but don’t yield more, so it’s important to hold off and apply it when it is need!
Potential Corn Issues
Recently in the area there has been the diagnosis of rootless corn syndrome and Goss’s wilt. In short, with the hot, dry and windy weather earlier in the season than normal, some corn was unable to develop its roots as normal and at risk for lodging. Tom Hoegemeyer, Professor of Practice, Department of Agronomy explains this problem along with management strategies on cropwatch.unl.edu.
The UNL Plant and Pest Diagnostic Clinic has received several samples from south central and eastern Nebraska which tested positive for the leaf blight phase of Goss’s bacterial wilt and blight. This early occurrence could have a severe impact on susceptible hybrids, but one needs to be scouting for it, especially in fields where hail damage has occurred, susceptible hybrids and fields with a history of the disease. Once again, if you think you have it, be sure to bring samples to the office so we can send them to the lab for a positive confirmation. More details can be found on cropwatch.unl.edu.
Weed Resistance Management Field Day 2012
Those interested in weed resistance management should attend the 2012 Weed Resistance Management Field Day. This program will be offered in two locations:
- Big Springs on Wednesday, July 11th
- David City on Thursday, July 12th
This program will include University and Industry presentations describing herbicide resistance and delivering a unified message about the need for integrated weed management programs to delay the evolution and/or spread of herbicide resistant weeds. Specific topics include glyphosate-resistant kochia at Brule and glyphosate-resistant giant ragweed at David City. The event will be concluded with a talk on how glyphosate-resistant weeds have changed agriculture in the southern US.
There is no cost to attend the Field Day and a complimentary meal will be served for those who have pre-registered. Participants are invited to register by Friday, July 6th so appropriate plans can be made for meals, teaching resources and tour logistics. This program is sponsored by the Nebraska Soybean Board.