Crops face mid-season battle with weeds and diseases

July 26, 2024 39

BLOOMINGTON (FarmWeekNow) — Airplanes, ground rigs, and drones can be seen across the state at this point in the season as corn and soybean crops battle weed and disease pressure.

“There are a lot of variables out there right now that everybody is trying to factor in,” FarmWeek CropWatcher Jeff Guilander told the RFD Radio Network.

He said they have found mild, yet widespread infestations of tar spot in Jersey County. But since he was able to plant a lot of his corn in April, the tar spot showed up about 20 days after tasseling.

“Which is kind of that gray area where you’re working more to save plant health than the yield potential at that point,” Guilander said.

The Jerseyville farmer said tar spot could get a tighter grip on the crop with higher temperatures and humidity in the forecast, adding that gray leaf spot and southern rust are starting to show up too.

“You can really tell the ratings they give these hybrids, as far as disease pressures and how they react to them,” he said. “If you’ve got one that you know is susceptible to a disease, you’re going to see it. It’s there.”

In the soybean fields, Guilander is concerned about waterhemp and shattercane, which he said have “come back hard” following recent rains.

“I don’t think we want to spray a whole lot because these weeds have kind of hardened off and they’re big and they’re going to be really hard to kill,” he said. “So, I think we’re just going to have to grind through a few of those this fall.”

crops weeds diseases — CATRINA RAWSON PHOTO An aerial applicator applies pesticide during a steamy afternoon.

In a recent CropWatcher report, Guilander said crop scouts are likely working overtime to diagnose agronomic threats.

“I did see beans with some yellowing in the leaves. I haven’t quite figured out what’s going on. It could be a sudden death issue or it could be something else,” he said. “Just when you get this type of very high-yield environment you could have a lot of things working against you also.”

He noted that insect pressure has been mellow but animals like deer and groundhogs are taking their fair share out of the field edges.

Guilander also mentioned the moisture picture has been much better than last season.

“Last year we had a completely dry June,” he recalled. “We got a few rains in June this year and have gotten even more here in July.”

USDA reported as of July 22 topsoil moisture for the state was considered 78% adequate and 6% surplus with subsoil moisture considered 72% adequate and 5% surplus.

Guilander said despite the challenges, he is optimistic for good-yielding crops.

“There’s going to be a lot of really good corn and beans at this point, but there’ll be some zeros too,” he said. “This crop hasn’t hit the bin yet, but hopefully we’re starting to see the finish line at this point.”

According to USDA, 80% of Illinois corn was silking and 18% was in the dough stage on July 21, both ahead of the five-year average pace. The majority of soybeans (81%) were blooming and 42% were setting pods, well ahead of average.

Illinois soybeans were rated 17% fair, 64% good, and 12% excellent as of the same date, while corn was considered 17% fair, 59% good and 16% excellent.