INDIANAPOLIS — Indiana farmers have done everything they can for their corn crop. Now, it’s up to the sun and Mother Nature.
“We need roughly another 30 days of good weather to help finalize the black layer,” said Jason Harmon, DEKALB Asgrow technical agronomist for northwest Indiana.
Harmon said right now and until harvest, weather will be the deciding factor on a crop that is at various stages of growth.
“Some of the earlier corn that was able to get put in on those drier soils or tiled fields, we are pushing late R5, while the majority that we’ve seen, a lot of it was planted late May to early June, we are actually still rocking the R4 stage, trying to get to R5. The corn seems to have shown it is maturing faster as these temperatures are changing,” Harmon said.
Kernel depth is a primary focus as far as yield goes for the crop, after having made it past some early season concerns.
“There’s a lot that can be done with kernel size. That’s what we are focused on now. We made it past the extremes of pollination, and when it turned really dry, we did have a little tip-back, but not as bad as I was thinking we’d see,” Harmon said.
Harmon said two disease issues could yet pose issues at harvest time and should be at the top of the list when it comes to field scouting and prioritizing fields for harvest.
“Gray leaf spot came in pretty quick, and we saw it in every field. It sat because it kind of draws second fiddle to tar spot and southern rust,” he said.
However, gray leaf spot may be making a return appearance.
“It can shut down and it can start up whenever it wants to, so as the moisture started in again, it is starting to spread throughout the canopy, but I think we will be far enough along and anybody that utilized fungicides and planted DEKALB Disease Shield products will be pleased,” Harmon said.
On Aug. 26, Darcy Telenko, field crops pathologist with Purdue University, confirmed that tar spot had been found in two more counties in Indiana and that tar spot was confirmed in a line of northernmost Indiana counties bordering Michigan, including Lake and Porter counties.
On Aug. 30, Telenko confirmed that she has found both southern rust and tar spot in the same fields.
Harmon said tar spot can make stalks vulnerable, leading to harvestability concerns.
“Ultimately, it quickly destroys the photosynthesis power plant of the leaves, so it cannibalizes the nutrients in the stalk to be able to finish the ear out and that makes it completely vulnerable,” he said.
Harmon warned that farmers need to be on the lookout for anthracnose stalk rot, as well.
“I have a hunch we’ll see a lot of it. I think farmers need to be proactive in doing some stalk testing when they are out there. Look for ghosting of the top of the plants and do some push tests to see where they are at because I’d hate to have a field get put back on the harvest list that could have been helped by getting it out of the field sooner rather than later,” he said.
One decision that may have made a difference for farmers is the decision to apply fungicide.
“It doesn’t exactly change the amount of GDUs collected. It just allows the plant to stay alive longer and you are just adding water, which is ultimately yield in that kernel depth. You probably will have a point or two of moisture difference, but when it’s already pretty wet, the drydown is going to be the same and we’re after the yield. We always like to have that corn be as strong as it can, and the best way to do that is to keep it healthy as long as we can,” Harmon said.