Insect & Pests

All Insect & Pests Content

Paul O. Johnson making notes about a field of corn

SDSU Extension to Tackle Weed, Pest and Drought Inquiries at State Fair

August 23, 2021

To address drought concerns, as well as weed and pest inquiries, South Dakota State University Extension will feature two booth locations at the 2021 South Dakota State Fair Sept. 2-6 in Huron.

Green and brown grasshopper with two yellow lines that originate on the head and meet on the abdomen.

Will Grasshoppers Be an Issue for Winter Wheat Emergence in 2021?

Grasshoppers were an issue in some areas of South Dakota during 2020 and continue to be an issue for several parts of the state in 2021. Drought conditions throughout the state aren’t helping, as grasshopper populations are limited on available food.

Three bees. From left: metallic native wild bee, brown native wild bees and bumble bee.

Pollinators Are Active in Sunflower

While scouting sunflowers, it’s hard to not notice the constant buzzing present in the field, which is produced by numerous species of bees. While sunflower varieties grown in the United States were bred for self-fertility, there is evidence that both honey bees and native wild bees can improve pollination.

Small, reddish-orange beetles on a green sunflower bud with a larger grey beetle also present.

Red and Gray Sunflower Seed Weevil Identification

While scouting sunflower, it’s not uncommon to observe both red and gray sunflower seed weevils on the same developing head. Differentiating these two species isn’t difficult, as there are obvious size and coloration differences.

Mosquito resting on a dandelion seed head.

West Nile Virus Update: Aug. 2, 2021

As of Aug. 2, 2021, the South Dakota Department of Health indicated that West-Nile-virus-positive mosquitoes were detected in Brookings, Codington, Hughes, Lincoln and Brown counties in South Dakota.

Small, brown insect with tail.

Springtails Are in My Home

During the last few weeks, we have been receiving an increased number of questions regarding very small insects that jump very far. It didn’t take long to determine that the hordes of small insects are springtails.

Red-brown colored weevil with bent antennae originating on the elongated mouthparts.

Red Sunflower Seed Weevils Are Active

Red sunflower seed weevils are active in South Dakota sunflowers. We noticed that many fields at R5 stages are already being sprayed, but scouting should still continue in those fields after application, and it should begin for fields that will reach the R5 stage within the next week.

Adult twospotted spider mites crawling on webbing that is attached to a leaf

Two-Spotted Spider Mite Populations Reaching Threshold

Drought conditions have continued and worsened in much of South Dakota during this season. As a result, two-spotted spider mite populations have been present in most fields and have recently had large population growth in soybean fields throughout the state.

Brown snailcase bagworm cases on the white underside of a jar lid.

Snailcase Bagworms in South Dakota

A unique insect that has been observed in South Dakota is the snailcase bagworm. Snailcase bagworms are wingless moths that spend their entire life in spiral-shaped “snail” cases, which they build around themselves using a combination of silk, soil particles and fecal matter.

a black beetle covered in a white substance

Gray Sunflower Seed Weevils

Gray sunflower seed weevils have been spotted in sunflower fields this week. Although they are a non-economic pest there are times when they can have population outbreaks and reduce sunflower yields.