What a contrast from one year ago! If you're keeping track of 90-degree maximum F- Degree temperature days or higher, this summer ahs already surpassed last summer byt posting a large number of warm days this year in most areas. In 2009, a cool July contributed to a big corn crop, Temperatures wee much cooler compared to this summer.
Does that mean yields will be lower this year, since corn likes plenty of moisture and relatively cool conditions during pollination? Such notables as Jim Newman, Lafayette, and Dave Nanda, Indianapolis, Ind., have noted that too much of a goods thing, such as t much heat when corn is growing and pollination, can hurt yields.
Newman, a former climatologist, now retired, says that if corn doesn't get a chance to regroup at night, processes within the plant don't go as well as they could. Nanda agrees. It has to do with natural processes, such as respiration, and other things related to photosynthesis.
Heat is one factor that some agronomists pay attention to when explaining why even irrigated corn doesn't yield as well in very hot years as in cooler summers.
The other issue this year is the constant pattern of rainfall during mid-July in many areas. While moisture is preferable when corn pollinates and matures, it sets up plants for diseases, especially when accompanied by high humidity. There's been no shortage of those kind of days
So it's not surprising that reports of gray leaf spot are streaming in. Now plant pathologists at the University of Illinois reports Goss' wilt is also being noticed and reported in that state. Other diseases will also likely appear, at least those favored by damp, humid conditions and high temperatures.
The hall mark for the summer will be to scout fields, beginning with the ones you know have susceptibility to certain diseases. If you don't know, check with out in your field. Scouting may really pay. It won't be the most glamorous job of the summer, but it could be the one that returns the most band for your buck.