Get more out of soybean post-applications

ATLANTA, Ind. — Mitigating crop stress while keeping fields weed-free is a top priority as young soybean plants develop.

Beck’s Practical Farm Research location lead Tyler Schindel and operations manager Collin Scherer gave their post-spraying recommendations for building the right herbicide program based on PFR trials in the latest episode of “The Dig.”

“This is one of my favorite times of year, because every soybean field either looks incredible, or it looks like it’s hanging on by a thread,” Schindel said.

“There’s no real middle ground. It’s either, these beans are gonna make 90, or you’re gonna walk away from the field immediately, start blaming the weather, the planter, or yourself, usually in that order,” Scherer added.

Weeds remain a top priority, and building a soybean herbicide program has changed dramatically from a decade ago with different trait platforms, resistant weeds, tank mixes and application cutoffs.

“It used to be pretty straightforward. Now, one wrong tank mix and suddenly you’re reading labels in the field like you’re studying for finals,” Schindel said.

Beck’s created a herbicide guide to help farmers build herbicide programs on the soybean platforms they’re planting.

“Whether that’s Enlist, Xtendflex, or non-GMO soybeans, the guide then it takes it another step further by helping match programs to weed pressures, while also showing strength, weaknesses and ‘watch outs’ for each option,” Scherer said.

“The back of the guide might be my favorite part. That’s where you’ll find application cutoffs, plant-back restrictions and the rainfast table, which gets really important when the radar suddenly turns yellow and your sprayer is six miles from the truck. My herbicide guide basically lives in the sprayer all summer,” Schindel said.

The guides can be downloaded from the Beck’s website.

Post-Pass Nutrition

“Once weed control is handled, the post pass also becomes a really good opportunity to feed the crop,” Schindel said.

“PFR data continues to show that foliar nutrition can be a profitable addition during soybean post applications, especially micronutrients. A lot of these nutrients are needed in small amounts, but they aren’t always supplied efficiently through traditional dry fertilizer programs.”

“Soybeans are weird like that. You can have plenty of fertility out there overall, but if conditions limit uptake at the wrong time, the plant still ends up short,” Scherer said.

To start, the PFR Proven foliar nutrition list provides recommendations based on field trials. For a product or practice to become PFR Proven, it must continuously provide positive yield gains each year and average an increased return on investment for a minimum of three years.

“One thing that stands out immediately is how often manganese shows up in the top performing products applied at V4. Whether it’s Versa Max MN, Max-IN Ultra Manganese, or several others, manganese is the common denominator,” Schindel said.

“Which makes sense because manganese is such a big role in photosynthesis and plant metabolism, and if you’ve ever walked in your field where manganese is deficient, soybeans will let you know pretty quick,” Scherer added.

“They don’t exactly hide it. So, if you’re making an early post application, manganese is probably the first nutrient you should evaluate,” Schindel said.

Later in the season, around R1, when soybeans begin flowering, the focus shifts more toward boron.

“Boron’s timing window in soybeans is a little bit wider than a lot of people think, because soybeans flower for such a long period of time. It helps with pollination, pod set, reproductive development — basically all the things we care about once the plant starts building yield,” Schindel said.

“What’s interesting is that boron is one of the few nutrients in PFR testing where multiple applications have actually shown positive returns, which usually gets people’s attention pretty quickly.”

Stress Reduction

Even if a soybean variety is herbicide-tolerant, doesn’t mean the application is completely stress-free.

“This is probably one of the more interesting things PFR has looked at recently. In Beck’s stress mitigation work, soybeans were intentionally stressed with Flexstar herbicide to evaluate products that could help plants recover quicker afterward. Visually, you could absolutely see differences in crop response and recovery,” Schindel said.

“Especially a couple of days after the herbicide application, some plots looked like they got into a fight,” Scherer added.

“Flexstar has a way of turning soybeans ugly in a hurry. The highest returning product in that testing was Exceed Nano Brown Sugar. But the theory actually makes sense. It’s a sugar cane extract with humic acid, and the idea is that the quick energy source helps the plant recover faster after stress,” Schindel said.

“And at only a few dollars an acre, it’s one of those things that may be worth trying on your farm.”

Exceed Nano Brown Sugar helps raise plant glucose levels, increases soil microbial activity and aids in increasing absorptions of essential minerals.

“This gets even more interesting when you look at our new herbicide application crop response study from PFR. Even herbicides that Enlist soybeans are fully tolerant to, things like Roundup, Liberty, Enlist One, still show yield reductions at that R1 growth,” Scherer said.

“The crazy part was there often weren’t obvious visual symptoms. The soybeans look perfectly fine, but the plant still has to metabolize that herbicide application and that process takes energy. Sometimes the best thing for the soybean is just leaving it alone,” Schindel said.

“That’s kind of hard for a farmer to do sometimes. We always want to be doing something, but seriously anything we can do to reduce unnecessary stress probably matters. Maybe that’s targeted spray technology. Maybe that’s stress mitigation products. Maybe it’s simply better application timing. All those little decisions can stack together over the course of the season.”