Weeds & Invasive Plants

All Weeds & Invasive Plants Content

A field divided into two planting areas. The left area has young corn plants emerging from the soil. The right has no visible corn emergence yet.

Grassy Weeds

Grassy weeds are a problem in all field crops. They must be identified at early stages of growth so they can be controlled before crop yields are seriously threatened. Control measures are not the same for all grassy weeds, so accurate seedling identification is important.

Waterhemp growing at he edge of a soybean field nearing harvest.

Checking Weed Control at Harvest

With harvest now in full swing, don’t forget to look at your fall weed control. What are the weeds that are left in your crop? Do you know what weeds they are? Is there a weed that you do not know?

A yellow dandelion growing among fall leaves in a yard.

Fall Lawn Weed Control

Fall is the time to control tough perennial broadleaf lawn weeds. The target weeds in the fall are dandelion, ground ivy, creeping bell flower, field bindweed and white clover.

a man standing in front of a cornfield

SDSU Extension Weed Evaluation Extension Demonstration Available at South Dakota State Fair

September 01, 2020

The SDSU Extension Weed Evaluation Extension Demonstration project will be available to the public at the South Dakota State Fair September 2-September 7.

Black caterpillars with white stripes feeding on green Canada thistle.

Thistle Caterpillars Showing Up on Canada Thistle

This week we received reports of caterpillars feeding on Canada thistle. After taking a look at the caterpillars, we determined that they are thistle caterpillars. However, we typically don’t see thistle caterpillar activity in S.D. until July or August. So why are they showing up so early this year?

A wet, unplanted field with water pooling and running off into a ditch.

Is Herbicide Carryover a Concern in Wet Weather?

Wet conditions have forced the need to change planting plans. In some cases, crops are planted in areas that were not planned for that crop this year. One factor in moving crops that cannot be overlooked is carryover. Does the ground to be planted have a carryover restriction for the desired crop to be planted?

A color-coded map of the United States indicating precipitation outlook for June 2019.

June 2019 Climate Outlook for South Dakota

As South Dakota emerges from the wettest 12-month period in 124 years of climate recordkeeping (June 2018-May 2019), June has started warmer and drier than average. The outlook, however, turns towards cooler and wetter than average again for the middle of the month.

Color-coded map of the United States indicating predicted precipitation for July 2019. South Dakota is set to experience above normal precipitation.

July 2019 Climate Outlook: Challenges Continue

This year’s seasonal pattern of wetter than average conditions is projected to continue through July and the rest of the summer season. The latest climate outlook, released June 20, 2019, shows an increased chance of wetter than average conditions in the next one to three months for the state of South Dakota.

A color-coded map of the United Statees showing the precipitation outlook for August through October 2019. All of South Dakota is light green. Parts of Western South Dakota are a darker green.

Wet Conditions Likely Into Fall Season

Many locations in South Dakota have already received as much precipitation this year as they do in an entire average year. The latest climate outlook from NOAA’s Climate Prediction Center shows increased chances of wetter than average conditions to continue into the fall season.

A color-coded map of the united states indicating temperature outlook for August 2019. South Dakota is mostly covered in blue.

August 2019 Climate Outlook: Cool and Wet

According to the latest climate outlook update, odds are favoring that August 2019 will be cooler than average. The update was released by NOAA’s Climate Prediction Center on July 31, 2019.