Hitting the Bull’s Eye When Switching Corn Hybrid Maturity

Joe Lauer, University of Wisconsin-Madison

This article first appeared May 2013

The 2013 corn growing season is off to its slowest start in a long time. On May 12 USDA-NASS reported  14% of the corn planted. The slowest start ever recorded was in 1984 when by week 19, only 14% of the corn was planted. Other slow starting years (by Week 19) were 1979 (15%), 1981 (20%) and 1993 (21%). Due to the slow start, especially for farmers in northern Wisconsin, many are considering whether they need to switch corn hybrid maturities. In the north, we really only have one opportunity to switch maturity and still have the potential for grain yield. In southern Wisconsin, we may have two opportunities to switch hybrid maturity. Although the penalty for late planting is important, growers also need to be careful to avoid tillage when soil is too wet. Yields may be reduced somewhat this year, but effects of soil compaction can reduce yields for several years to come. Your decision to switch hybrid maturity depends upon:

  • Desire to accept risk: Longer season hybrids offer the highest yield potentials, but may also increase drying costs and/or delay harvest.
  • Potential use: For dry grain, relative maturities should be shorter-season within the maturity range for the latest acceptable planting date. For ear corn, high moisture corn, and silage, relative maturities should be longer-season within the maturity range for the latest acceptable planting date.
  • Field conditions: Shorter-season hybrids within the maturity range for the latest acceptable planting date should be selected when field conditions include heavy crop residue, reduced tillage, and heavy soil textures.
  • Hybrid dry down and grain quality characteristics: Longer-season hybrids within the latest acceptable planting dates should have fast grain dry-down and high test weight characteristics.
  • Ease of trading original hybrids for superior shorter-season alternatives.

Please read the full article for the complete UWEX guidelines at  http://wisccorn.blogspot.com/2013/05/B036.html