Quite a few farmers throughout the northern half of Indiana are frustrated with the slow drydown of the 2023 corn crop, especially since some grain elevators are refusing to accept grain deliveries with moistures above certain levels, e.g., 27%. Some have also complained about corn not maturing (black layer) as soon as they think it should have. What’s going on this fall?
Some scuttlebutt down at the Chat ‘n Chew Cafe suggests both the slow maturation and drydown in the field this fall were caused by all those smoky hazey days back in early to mid-summer, courtesy of the wild fires in parts of Canada. I don’t buy into that theory. While it may be true that smoky haze (or cloudy haze for that matter) influences plant photosynthesis (and thus potentially grain yield), it does not DIRECTLY influence the rate of plant development (i.e., how fast plants mature).
Rather, it is primarily temperature that drives the rate of plant development (Nielsen, 2020). The warmer it is, the faster corn progresses through its growth stages. The cooler it is, the more slowly corn progresses. The smoky days may have INDIRECTLY contributed to the slower maturity if they contributed to cooler temperatures. However even if that was true, the cooler temperatures did not occur ONLY on those smoky days.
The climatological evidence suggests that the 2023 growing season was generally cooler than normal throughout and not just due to smoky days. The accompanying chart comes from the GDD Corn Tool developed by the “Useful to Useable” USDA-funded project (https://mygeohub.org/groups/u2u/purdue_gdd). To create the chart, I chose Blackford Co. in eastcentral Indiana, a 109-day hybrid maturity, and a May 19th planting (background information for one of our on-farm sulfur trials that is still running about 30% grain moisture as of about Oct. 23rd). The GDD Tool estimated that black layer did not occur until Oct 4th, which was exactly what our cooperator told us happened.
Source: purdue.edu
Photo Credit: gettyimages-chrisboswell
Categories: Indiana, Crops, Corn