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Diseases & Disorders

All Diseases & Disorders Content

People eat ice cream under a large tent
Aug 18

Dakotafest

Stop by the SDSU Extension booth at Dakotafest to meet specialists, ask questions, get recommendations and learn about programming and events.

Two coneflowers with distorted heads due to Aster yellows phytoplasma.

Aster Yellows - Plant Pest on the Plains: How you can get involved in this important research

Aster yellows phytoplasma, best known as Aster Yellows disease or Onion Yellows disease, is commonly observed in purple coneflowers across the Great Plains. SDSU Extension is monitoring and modeling its distribution in the region, and you can help!

tall trees in the Black Hills

Tree Pest Alert

From seasonal issues and timely recommendations to disease diagnosis and expert advice, the Tree Pest Alert is a trusted resource for selecting, planting and caring for trees and shrubs all year round.

Three wheat fields exhibiting wheat streak mosaic virus symptoms throughout.

South Dakota Wheat Streak Mosaic Virus Disease: 2026 Update

Wheat streak mosaic virus is on the move across South Dakota wheat fields. Due to the mild winter and overwintering in winter wheat, viral activity has had a jump start in 2026, and the occurrence and intensity of disease pressure is comparable to the 2025 season.

Testing Center on the South Dakota State University campus.

SDSU Extension Pesticide Applicator Testing Locations

Whether you are interested in becoming certified as a private or commercial pesticide applicator, SDSU Extension is proud to offer in-person pesticide applicator testing locations throughout South Dakota.

Small group of calves in a feedlot.

Vaccinating Early-Weaned Beef Calves

In most years, pre-weaning vaccinations are a task completed in early fall. However, in dry years, poor pasture conditions forcing producers to wean calves early may push up that timeline.

Dense swarm of mosquitoes in the evening sky

West Nile Virus Update: July 2, 2026

On June 15, 2026, the South Dakota Department of Health released a press release that the first West Nile Virus positive pool of mosquitos was detected in Brown County. Although much of the state is still experiencing drought, recent heavy rains will promote already active mosquito populations.

Color-coded map of South Dakota showing Fusarium head blight risk throughout the state. For a detailed description, please call SDSU Extension at 605-688-4792.

Tools Available for Fusarium Head Blight Prediction

Fusarium Head Blight (FHB), commonly known as scab, is a major disease threat for wheat each year during the flowering growth stage. To support growers in making informed fungicide decisions, forecasting tools are available that use weather data to estimate the likelihood of scab development.

Two producers moving cattle out of a shelter.

Biosecurity for Beef Cow-Calf Operations: Managing the Entry of New Animals

Infectious disease can impact cow-calf operations in dramatic ways. These steps should be considered the minimum standards for introducing new animals into cow-calf operations to avoid the spread of infectious disease.

Cleaned, emptied pesticide containers on a concrete workshop floor.

South Dakota Pesticide Container Recycling

The South Dakota Department of Agriculture and Natural Resources is again offering pesticide container recycling services across the state. View a complete list of 2026 dates and locations.