June 26, 2019
Issue 5

Forage, Prevented Plant Acres:  This USDA RMA website discusses forage, haying and grazing on prevent plant acres since the harvest date change to September 1 2019.
Forage options on Prevented Plant acres:
  • Consider 1.5 bushel/acre of oats or other small grain for ground cover only. Fall growth will be better if the small grain is seeded mid-summer.
  • Consider corn harvested as silage. Corn for silage - even planted in mid-summer - will provide a high yield of high quality forage compared to other summer annual crops.
  • Other summer annuals - such as pearl millet, German millet and Japanese millet can be seeded mid-summer and can be harvested as a hay or bedding crop after September 1.
  • These websites have useful information regarding cover crops planted on Prevented Plant acres or emergency summer forages:
Thistle Caterpillar:     Thistle caterpillar have caused some defoliation damage to the soybean crop in some areas. This defoliation damage needs to exceed 30 percent to warrant treatment. The thistle caterpillars are expected to pupate soon. A second generation will emerge in mid-summer and usually do not cause significant defoliation damage.

First Generation Corn Borer:  Check fields that do not have the Bt trait for corn borer. The predicted warm weather may favor corn borer activity. One established larva per plant could produce a 6 % yield loss. This article has more info and a spreadsheet to help with corn borer decisions.

Growing Degree Days (GDD):  The following are GDDs and departures for some corn planting dates in three Crop Reporting Districts:

NW                 NC                  WC
April 21           742 (-185)       745 (-160)       815 (-170)
May 7              660 (-150)       655 (-130)       715 (-135)
May 16            610 (-100)       610 (-80)         670 (-80)
June 5              395 ( -35)        380 ( -30)        415 ( -30)
Prepared by:
  Paul Kassel- Extension Field Agronomist


Phone:  (712) 262-2264


Serving Clay, Buena Vista, Dickinson, Emmet, Hancock, Kossuth, Palo Alto, Pocahontas, Sac and Winnebago Counties



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