Will corn in Mid-Michigan reach maturity?
Late spring planting leads to late corn crop maturity.
Drive across Mid-Michigan and you will see fields of corn that are drying down and fields of corn that are still very green. That is not surprising based on the variable weather we experience during the spring of 2013. On June 1, 2013, about 10 percent of the corn in Michigan was still in the bag. Wet spring weather kept farmers, particularly in Mid-Michigan, out of the field.
Fast forward to mid-September and we find that for the week ending Sept. 16, 66 percent of the Michigan corn crop was reported to be at the dent stage of development. Corn in the early dent stage may take as many as 25 days to reach full physiological maturity. Corn that is fully dented may reach black layer in 10 to 15 more days. However, the 7 percent of corn that is in the late milk-dough stage may need as many as 35 days to mature.
An early killing frost is the biggest threat to late maturing corn. A killing frost is usually defined as sustained temperatures below freezing or short periods below 28 degrees Fahrenheit. Sept. 17 brought killing frost to low lying areas of central Michigan when overnight temperatures dropped below freezing. Long-term averages indicate there is a 50 percent probability of receiving a killing frost in Mid-Michigan by Oct. 8 in a normal year, based on 30 years of data (1961-1990). Corn in the milk-dough stage at the time of a killing freeze will suffer significant grain yield and quality loss (50 to 70 percent). However, if corn matures to the fully dented state by the time of a frost event, yield losses may only be in the 5 to 10 percent range. Grain quality is also likely to be impacted as growers can expect lower test weights and may see more kernel damage.
There is a lot of variability in how close corn is to physiological maturity across Michigan. Fields that escaped killing frost on Sept. 17 may still have a reasonably good chance of reaching maturity, given the return of warmer conditions in the forecast.
To see progress in growing degree day accumulation and to view overnight low temperatures for your area, visit the Michigan State University’s Enviro-weather website. For more information on frost damage on corn, see the Michigan State University Extension Harvest Alert, “Potential for Frost Damage and Other Effects in Corn.”