Missouri Ruralist logo

Don’t host a kegger in your bean field

Remove these three pod-feeding insects from the soybean scene to avoid yield loss.

Mindy Ward, Editor, Missouri Ruralist

July 11, 2023

3 Min Read
 Green stinkbug nymphs are about to emerge from their eggs
ON TAP: Green stinkbug nymphs are about to emerge from their eggs. To some, they look like beer kegs set up on their sides. Merle Shepard, Gerald R. Carner, and P.A.C Ooi, Bugwood.org

It may not be a rager, but a pod feeder may already be partying in your soybean field — and you don’t even know it.

Farmers often notice when leaf feeders attack a bean field because of the visible holes on the leaf’s surface. However, pod feeders often hide under the canopy, relatively unnoticed, but causing irrevocable damage.

One of the worst cases of pod feeding on soybean plants was in 2015, says Scott Dickey, regional agronomy manager for Beck’s Hybrids.

“It made it clear to Wisconsin, taking pods off plants like crazy,” he says. “We sprayed a lot of acres, but in most cases, we had already seen up to 50% of our yield loss before treatment.”

During the inaugural Beck’s Bash in late June at Missouri Soybeans Bay Research Farm outside of Columbia, Mo., Dickey shared his top three pod-feeding bugs to worry about and how to treat them. They include:

1. Bean leaf beetle. This insect likes to scratch around the surface of the soybean pod, killing it.

2. Pod worm. This is a corn earworm that makes its way into a soybean field. It bores directly into the pod and eats the bean right out of it, Dickey says. “That’s just direct yield loss.”

3. Green stinkbug. These damage stems and pods, causing pod drop, yield loss and reduced seed quality. Damage from stinkbugs can be similar to damage from drought.

Farmers need to pay attention to all three, but Dickey homed in on the green leaf beetle. “To me, this is the No. 1 pest in beans in Missouri right now,” he says.

It’s not a tick in your field

Dickey hears many farmers talk about ticks in their soybean fields. “I can about guarantee you that 99% of the time, they are green stinkbug nymphs that just hatched,” Dickey says.

Their eggs look like a “beer keg standing on end,” he explains. They have a fringe of hairs on the top. “They’ll pop the cap open and little bitty tiny versions of these guys will come out about the size of a tick.”

The nymphs have black and orange stripes on their backs. When they reach maturity, they are closer to the size of an adult green stinkbug.

What concerns Dickey is that at all phases, green stinkbugs have a proboscis for a mouth that can probe into the soybean pod. “Whatever they inject kills the bean in the pod,” he says.

That equates to yield loss. However, farmers should not simply walk through a soybean field and expect to find them.

Check for ID

Green stinkbugs like to hide. “It won’t be until after leaf drop that you see them,” Dickey notes. “By then, they’ve already done a lot of their damage.”

So, farmers need to turn the leaf over and look below the surface. If eggs or nymphs are present, treat the field.

“This is the No. 1 reason to put an insecticide with fungicides — to control insects,” Dickey says. He adds that an insecticide with an extended residual kills the hatchers as well and recommends talking with your agronomist for treatment options.

Dickey points out that farmers may want to stop “revenge spraying” when they see defoliated eaves and focus on yield robbing pod feeders in soybean fields.

About the Author(s)

Mindy Ward

Editor, Missouri Ruralist

Mindy resides on a small farm just outside of Holstein, Mo, about 80 miles southwest of St. Louis.

After graduating from the University of Missouri-Columbia with a bachelor’s degree in agricultural journalism, she worked briefly at a public relations firm in Kansas City. Her husband’s career led the couple north to Minnesota.

There, she reported on large-scale production of corn, soybeans, sugar beets, and dairy, as well as, biofuels for The Land. After 10 years, the couple returned to Missouri and she began covering agriculture in the Show-Me State.

“In all my 15 years of writing about agriculture, I have found some of the most progressive thinkers are farmers,” she says. “They are constantly searching for ways to do more with less, improve their land and leave their legacy to the next generation.”

Mindy and her husband, Stacy, together with their daughters, Elisa and Cassidy, operate Showtime Farms in southern Warren County. The family spends a great deal of time caring for and showing Dorset, Oxford and crossbred sheep.

Subscribe to receive top agriculture news
Be informed daily with these free e-newsletters

You May Also Like