Weeds & Invasive Plants

All Weeds & Invasive Plants Content

Producer with tablet observing a field in late autumn.

Critical Period of Weed Control: A good, but not perfect guideline

The critical period of weed control is the period during a crop lifecycle when weeds need to be managed to avoid a significant yield loss.

A team of four people in matching blue button-down shirts stands on stage with their awards, with two people off to the right side

SD 4-H team wins national land and range judging contest

May 29, 2024

The Haakon/Bennett County 4-H range judging team won first place at the 2024 National Land and Range Judging Contest held from April 30 to May 2, 2024, in El Reno, Oklahoma. Team members include Bennett County’s Emily Zickrick and Haakon County’s Colden Kramer, Ashley Schriever and Tara Schofield.

A picture of a absinth wormwood plant that has white colored leaves.

Absinth Wormwood Control in the Spring

Absinth wormwood is a difficult-to-control, noxious weed that can produce great amounts of seed (50,000 seeds per-stem) and spreads only by seed, illustrating the importance of management prior to seed production.

Various weeds emerging from a research plot in some rows, while other rows are weed-free.

Weeds Are Starting to Emerge: Even After a Preemergence Herbicide Application

During recent scouting, weeds were noticed in plots treated with preemergence herbicides. Learn some troubleshooting considerations to help determine why some weeds emerge following preemergence treatments.

Top: Field pennycress leaves and seeds. Bottom: Shepherd’s purse leaves and seeds.

Early Season Prevalence of Field Pennycress and Shepherd’s Purse

Many fields that are planted to winter wheat or have yet to be tilled may have a healthy infestation of field pennycress or shepherd’s purse. Learn some expert tips for identifying and managing these weeds before they become a problem this growing season.

Canada thistle growing in a pasture.

Current State of Noxious Weed Management in South Dakota

Results of an online survey to determine how South Dakota stakeholders are currently managing noxious weeds.

A collection of empty pesticide and herbicide containers.

Herbicide Group Classification

The intent of providing herbicide group numbers and mode/site-of-action information on labels is to help develop herbicide plans that reduce the selection pressure on herbicide-resistant weeds. Learn how understanding this information can help improve your plans.

Nozzle on a boom sprayer in a crop field.

Factors Influencing Spray Coverage

Learn about the different factors that influence spray coverage and how you can tailor your practices to ensure that proper coverage is achieved.

Tractor-mounted wick applicator applying herbicide to a pasture.

Low-Cost and Adaptable Plans to Build a Wick Applicator for Herbicides

From crop fields to home gardens, wick applicators can manage weeds by applying herbicides directly to weeds growing at a set height above desirable plants. Learn how to build one yourself in this article.

Tractor spraying pre-emergent herbicide in a bare field.

Preemergence Herbicide Application Considerations for 2024

Preemergence herbicides control germinating weeds, which minimizes early-season competition with crops to keep yield potential higher. Learn what factors influence their effectiveness and what can be done to avoid control failures and unintended crop injury.