Integrated Crop Management News

The majority of Iowa is currently in moderate to severe drought, with west central Iowa under the most extreme drought. As if drought were not enough, we were dealt another blow with extreme and widespread wind damage on August 10, some of which overlapped the drought area. With these events come an increased risk for ear rots and associated mycotoxins. This article will address ear rots and mycotoxins of particular concern this year, in addition to scouting methods and monitoring considerations while grain is still in the field.

The dry conditions throughout large areas of Iowa during 2020 reminds us of Iowa’s last significant drought in 2012 and the subsequent impacts on nitrate-N levels in subsurface drainage the following spring. This article will address concerns for water quality in drought conditions and opportunities to reduce nutrient losses from fields this fall.

Extreme weather events may lead to a decision to make corn silage rather than harvest corn for grain, or to harvest acres that will exceed current silage storage capacity. Before harvesting for silage, make sure you have a market for the silage or a sufficient number of livestock to feed it to. It may be difficult to harvest good quality corn silage if the crop has weather damage and the economic value of the silage will likely be lower than silage from non-damaged fields.

The August 10, 2020 high winds (derecho) caused lodged or flattened corn in many Iowa fields. The corn development ranged mainly from stages R3 (milk) to R5 (dent). Some fields may not be harvested, some chopped for silage, and some harvested for grain. Nutrients such as nitrogen (N), phosphorus (P), and potassium (K) remaining in the field may be different than with normal harvest due to partial plant removal, grain harvest, or grazing. Therefore, adjustments can be made for future fertilizer or manure applications.