Insect & Pests
All Insect & Pests Content
Scouting for Grasshoppers in Pasture and Alfalfa
For 2019, we have either received reports of very high grasshopper numbers or of very low or nearly absent populations. Most reports of high populations have originated from areas near rivers and other waterways. This suggests that the rich foliage along the banks of waterways has provided excellent habitat for grasshoppers and has boosted their populations in those areas.
Checkerspot Caterpillars in Sunflower
While scouting sunflower near Sturgis this week, we came across outbreak levels of checkerspot caterpillars that were defoliating the plants. Similar sightings have been reported throughout Western and Central South Dakota in recent weeks.
Dectes Stem Borer Adults Active in Sunflower
In South Dakota, one of the insects that is commonly observed in sunflower is the Dectes stem borer larva. At this point in the season, adults are beginning to become active with females laying eggs in sunflower plants.
Black Vine Weevils Becoming Active
Black vine weevils are now showing up across the state. It is typical for the adult beetles to emerge in early summer and begin feeding on plant foliage. They primarily feed on lilacs and yews, both common landscape shrubs. Although the adults cause minimal damage, their larvae feed on the roots and can occasionally be a threat to ornamental plants, especially those grown in pots or containers.
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.
Flea Beetles Defoliating Canola in South Dakota
This year flea beetle emergence is behind schedule, but so is a lot of the canola emergence. We are observing very large flea beetle populations on late-planted canola that is just emerging. As a result, much of this canola is being heavily defoliated and will likely require foliar insecticide management.
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.
What to Do With Unusable Home and Garden Pesticides
As a gardener or homeowner, you may be wondering what you can do with your leftover pesticide products (including herbicides, insecticides, and fungicides), or maybe you bought a new home and the garage or basement is full of mysterious containers with no labels. If products are stored in garages or other areas with a lot of temperature changes, these products may become entirely unusable. So what to do?
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.
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.