Each week we will be offering the air Growing Degree Days (GDDs) for corn that have accumulated to date from 13 locations across the team's 8-county area.

Growing Degree Days for corn are Base 86/50 F and calculated by taking the average daily temperature, ((Daily Max Temp - Daily Min Temp)/2) - 50.  But the maximum temperature cannot be more than 86 degree F and the minimum less than 50 degree F.

See: Growing Degree Day Calculator

Harvest is underway throughout the region, but: We've noticed that fewer fields are being affected by the typical late-season foliar diseases this year, so green foliage may mislead you into thinking you still have time - so check your crop to make sure you're on schedule for silage harvest!

If you know your GDDs for your hybrid to physiological maturity (black layer) subtract off 150 GDDs to get you roughly the GDDs needed to silage harvest dry matter for that hybrid. However, tasseling dates serve as a better starting place to project corn silage harvest dates than planting dates. Silage harvest is likely to begin at about 800 GDDs after tasseling for 101-110 day hybrids and 750 GDDs for 96-100 day hybrids.  Using the GDDs after tasseling to harvest and the Climate Smart Farming Website's 15 year GDD data it is possible to make projections as to when corn silage harvest might begin.  Record Silking/Tasseling Dates for Corn Fields

Bunker silage should be ~65-70% moisture at harvest (30-35% DM), so if you have early-planted corn in some of the lower-lying areas (especially in the eastern part of the region this year!), take note of what stage you're at in the coming days and weeks: 

See the attached table for more of the September 11, 2020 results. See the attached pdf for a good guide on corn development and our reference for growth stages.