Content by Connie Strunk

Three bean leaf beetles. From Left: Brown beetle with black spots on a green leaf. Yellow beetle with black spots on a green leaf. Red beetle with black spots on a green leaf.

Bean Leaf Beetles Showing Up in Soybean

Despite the prediction of low overwintering survival we have observed bean leaf beetles in soybean this week. See our latest observations and management recommendations.

Green corn leaf with yellow rust-colored spots throughout.

Southern Rust Observed in South Dakota Corn Fields

Southern Rust was recently confirmed in South Dakota corn fields. Yield impacts from Southern Rust can be high, so scouting for the disease is highly encouraged to determine if it is present.

Corn leaf with trace amounts of tar spot.

Tar Spot Confirmed in South Dakota

Trace amounts of tar spot were recently found in Yankton and Bon Homme counties and are thought to have originated from corn residue instead of windblown spores. This speaks to the importance of crop rotation in the management of this disease.

Green wheat plants with some yellowing throughout.

Keep Watch: Wheat Streak Mosaic Virus is Developing in South Dakota Fields

Wheat Streak Mosaic Virus has been reported in South Dakota wheat fields and is also a major wheat disease for Great Plains states in 2025. The virus is sweeping across the state and is rampant in winter wheat.

Map of South Dakota with Mesonet stations marked with blue dots.

How to Use the South Dakota Mesonet Small Grains Tool

South Dakota Mesonet Small Grains Tool is an easy-to-use and efficient tool that can help identify disease risks associated with wheat leaf rust, wheat leaf spot diseases, and Fusarium head blight.

Crop Hour

SDSU Extension will deliver a series of virtual Crop Hour webinars January 7 to February 27, 2025, every Tuesday, Wednesday and Thursday from 10:00 a.m.-11:00 a.m. CST.

SDSU Extension to host tar spot webinar

January 24, 2025

Tar spot is a potentially yield-impacting corn disease that was confirmed in 46 of South Dakota’s 66 counties in 2024. The fungus can cling to crop residue over the winter and re-emerge once temperatures rise. It’s most commonly spread in South Dakota by wind-blown spores.

A plot of land from the side, with plant roots growing down into the soil

SDSU Extension 2025 Crop Hour webinar series starts in January

November 18, 2024

Crop Hour provides producers and industry professionals with information to navigate the
challenges and opportunities of farming in South Dakota. People can participate live via Zoom or watch the recorded presentations on YouTube.

Corn Stunt in South Dakota

In late September, a sample received from Deuel County was confirmed positive for corn stunt, a disease spread through corn leafhopper feeding. This diagnosis is the furthest north corn stunt has ever been confirmed and reported in the United States.

SDSU Extension to host disease scouting workshop for corn, soybeans

October 01, 2024

If you have been wondering what you’re seeing in your corn or soybean fields this season, join the SDSU Extension plant pathology team in Volga to see tar spot in the corn field and white mold in the soybean field, or to have your own diseased plant material identified.