A Certified Crop Adviser (CCA) in Michigan says a confluence of weather conditions resulted in a roller coaster ride for soybeans over the first two months of the growing season.
The good news is the plants still have time to catch up and recover on the back-end (if timely rains are consistent), but the early season issue is still causing a lot of growers to hang their heads in utter disgust when they head out in the morning and see large areas of small, yellow soybean plants in fields.
How did this happen?
In southern Michigan, northern Indiana, and northwest Ohio, most soybean farmers opted to plant early. That means the beans were in by end of April. The region then had the coolest average night temperatures in May of the past 14 years, followed by the warmest average night temperatures in June of the past 14 years.
A roller coaster ride indeed.
Missy Bauer with B&M Crop Consulting says that two-month yo-yo spell left the region’s soybean farmers battling the “largest carbon penalty the area has seen in 14 years.”
What is the carbon penalty in farming?
The carbon penalty Bauer refers to is the process where microbes in the soil come alive as soil temps gradually warm and start breaking down last year’s crop residue. The nutrients are then naturally converted to plant-available nutrients through mineralization.
Bauer says the warm-up occurred so quickly it created a sort of massive explosion of microbial activity in the soil. While that sounds like a good thing, she says it actually resulted in some essential early-season nutrients getting “locked up” in the soil, thus unavailable for plant uptake.
“How many calls did we take this year from farmers saying, ‘My beans aren’t growing right, why?’” says Bauer who also serves as a Farm Journal field agronomist. “We’re seeing the biggest carbon penalty we’ve had in 14 years, and this is a hard carbon penalty. It locked up the beans, and that added stress.”
How can I overcome the carbon penalty?
If you have liquid fertilizer technology on your bean planter, Bauer thinks it might pay off this year by offsetting the carbon penalty and helping beans battle that early season stress.
July is currently trending above average for growing degree days (GDD) in the Lake Erie region, which will help shift vegetative growth a gear or two higher and set beans on a course for canopy close and pod fill.
“Basically, we’re back on track (with beans),” Bauer says. “Maybe we’re just a little bit behind last year, but we had better heat units in May last year, too. Now, we’ve made-up for that GDD deficit heat unit-wise, we’re not quite all the way there, we’re still a little behind, but we’re knocking on average.”
Spray drone treatment for nutrient deficiency in soybeans an option, too
Recently, Kameron Barrow, field operations manager, teamed up with B&M owner and CCA Bill Bauer to address some nutrient deficient yellow spots in the operation’s test plots near Coldwater, Mich.
After tissue sampling the affected plants and finding out the culprit was most likely a manganese deficiency, Bauer and Barrow called up a local spray drone service provider and hired it to spot spray a 5% manganese liquid fertilizer over the canopy of the yellow soybean plants. The drone applied a rate of half a pound per acre of manganese.
“We came in and sprayed on July 10 and on July 15 we scouted and immediately those yellow spots are gone, and that’s only after five days,” says Barrow, adding they also left a nearby section of yellow plants untreated as a check. “This just shows we have access to spray drones now, and we can use the technology to use things we’ve never used to better manage the crop.”
