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Content by Adam Varenhorst

Group of small grey insects with clear wings on green plant.

Monitor Canola Fields for False Chinch Bug Activity

While scouting canola this week, I came across a field that had plants along the edge that looked like they were suffering from drought stress, but given the recent rain I doubted that to be the case. Closer inspection of the stressed plants indicated that they were covered in false chinch bugs. Although false chinch bugs are not normally an issue in canola, very large populations do have the potential to reduce yield.

Top view of a black colored ant inside of a clear plastic container.

Watch Out For Carpenter Ants

With the continued moisture and warmer temperatures, carpenter ants have become a more common appearance in South Dakota. Similar to termites, this insect can be a structural pest, causing damage to homes and other buildings. It is important to identify and treat carpenter ants early to prevent any potential damage.

Black and white county map of South Dakota, Minnesota, Nebraska and Iowa. Red dots within counties indicate soybean gall midge emergence. Black dots represent trap locations.

Soybean Gall Midge Are Emerging Around Us, But No Captures in S.D.

Last year, the soybean gall midge caused a lot of issues in soybean, including lodging and up to 50% yield loss. In an effort to determine when soybean gall midge adults are emerging in 2019, a network of emergence traps has been established in South Dakota, Nebraska, Iowa and Minnesota. So far, emergence of the adult soybean gall midge have been reported from Iowa, Nebraska and Minnesota.

Small black fly.

What Are Those Little Flies That Keep Biting Me?

If you have been swarmed and bitten by small black flies this year, you’re not alone. The culprits of these bites are commonly referred to as black flies or buffalo gnats. The reason we are noticing so many in 2019 is likely due to favorable spring conditions that included a lot of moisture.

United States Environmental Protection Agency logo.

Cancellation of Several Neonicotinoids

On May 20, 2019, the United States Environmental Protection Agency announced the cancellation of registrations for 12 products that contain neonicotinoid insecticides. The cancellation of the product registrations was voluntarily requested by the companies that had registered the products.

Numerous grayish-brown bugs gathering on the stems of a Brassica plant.

False Chinch Bugs in the Garden

Swarms of false chinch bugs have started appearing in South Dakota this month. Although they are typically only a nuisance pest, their populations can become magnified during cool, wet springs (like this year). In high abundances, false chinch bugs can pose a threat to garden plants, especially Brassica plants such as broccoli, cauliflower, turnips, and cabbage.

Three types of plant bugs. From left: Meadow plant bug, Lygus bug, and alfalfa plant bug.

Plant Bugs Showing Up in Alfalfa Fields

Plant bugs are now becoming active in alfalfa fields across the state. A common question we receive is why some of these bugs looks so different from others. There are actually three different types of plant bugs that commonly appear in alfalfa fields: meadow plant bugs, Lygus bugs (aka tarnished plant bugs), and alfalfa plant bugs.

Green beetle larvae with white stripe and brown head.

Alfalfa Weevil Activity: June 7, 2019

Quite a few degree days were accumulated over the course of the last week. Alfalfa fields should be closely monitored for alfalfa weevil activity for the next couple of weeks, even in areas where degree days indicate the alfalfa weevils are pupating.

Young corn plant with three circular feeding holes in a leaf.

Black Cutworm Caterpillars Are Actively Feeding in South Dakota

We received numerous reports this week of small holes in V1-V2 corn plants. The holes are the result of early instar cutworm caterpillar feeding and, more specifically, black cutworm caterpillars. After hatching, black cutworm caterpillars initially feed on the leaves. As they develop and become larger, they pose a clipping or cutting threat to corn.

Teardrop shaped green insect with long legs and antennae on a lighter green leaf.

Pea Aphid Populations Increasing in Alfalfa

While scouting alfalfa this week, we noticed pea aphid populations are starting to increase. The forecast is looking favorable for this pest, so it will be important to continue monitoring populations prior to and after the first cutting.