Content by Madalyn Shires

Two broccoli plants exhibiting early black rot symptoms.

Black Rot of Brassica Crops

Black rot is an uncommon, but devastating bacterial disease in South Dakota that can develop during extended periods of hot and wet weather, leading to rapid and widespread crop loss.

Dark-green gelatinous masses on a patch of grass.

Nostoc in Lawns

Nostoc is a genus of cyanobacteria that form colonies in gelatinous masses. In South Dakota, it commonly appears in home lawns, notably in patches where grass is not growing, especially after periods of rain.

Dried corn growing in a field with visible damage and molding.

Mycotoxins: Should you be concerned?

Environmental stress caused by the weather or damaged crops increases the potential for mold and mycotoxin development. Learn some answers to common questions about mycotoxins and how to manage them.

A corn leaf is shown

SDSU Extension to host corn disease scouting workshop

September 23, 2025

South Dakota State University Extension will host a scouting session for corn diseases confirmed in the state this season.

Multi-rotor drone used for spray, spread and seeding

Required Licensing For Applying Pesticide Using Spray Drones

Fact sheet for South Dakota stakeholders wanting to get certified to apply pesticides with a spray drone.

A green corn leaf with yellow to brown spots throughout.

Corn Disease Update: September 2, 2025

As of September 2, 2025, a number of corn diseases have been reported and confirmed throughout South Dakota. View our latest findings as we approach the fall harvest season.

People stand in a field listening to a person speak

SDSU Extension programs help producers maintain healthy crops

August 26, 2025

Madalyn Shires puts on a lot of miles in the summer. As an assistant professor and SDSU Extension Plant Pathology Specialist, Shires traverses the state visiting research plots and educating crop producers on that research.

Coneflower with Aster yellows disease.

Aster Yellows Phytoplasma

Aster yellows is a phytoplasmal disease carried and introduced by aster leafhopper. It is known to infect over 80 different plant families, as the aster leafhopper has extremely broad feeding habits.

Corn leaf samples with Southern Rust and Tar Spot.

Corn Diseases in South Dakota Update

Several South Dakota counties have confirmed positive cases of Southern Rust and Tar Spot this growing season. See our latest recommendations for dealing with these diseases before they become a problem.

Green wheat leaves with yellow streaks throughout.

Wheat Streak Mosaic Virus Complex: Breaking the Green Bridge

As wheat harvest proceeds, it won’t be long until winter wheat planting is underway in South Dakota. To effectively reduce wheat streak mosaic virus, it is important to manage the green bridge effect to slow spread of disease in newly emerging wheat fields.