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All Sunflower Content

aerial view of South Dakota farm and surrounding land

Pest & Crop Newsletter

SDSU Extension publishes the South Dakota Pest & Crop Newsletter to provide growers, producers, crop consultants, and others involved in crop production with timely news pertinent to management of pests, diseases, and weeds in South Dakota.

A hand examining a wheat plant in a wheat field

USDA to Collect Information on Small Grain Production in South Dakota

September 20, 2019

South Dakota will be one of 32 states taking part in a small grains survey conducted by the National Agricultural Statistics Service (NASS) of the United States Department of Agriculture this fall.

Wheat, Oats, Sorghum, Sunflower, Corn

sunflower field

An identification guide to Common Stem Diseases of Sunflower in South Dakota

A guide of common stem diseases in sunflowers in South Dakota

Symptoms of three emerging sunflower diseases. From the left: Bacterial Stem Rot, Sclerotinia Basal Rot, and Sunflower Rust.

Bacterial Stem Rot, Sclerotinia Basal Rot and Sunflower Rust Developing in Sunflower

Sunflower scouted this week in Brookings and Kingsbury counties were found with bacterial stem rot, Sclerotinia basal rot and sunflower rust. This area has had plenty of moisture, which favors several diseases to develop in sunflower.

Two sunflower seed weevils side-by-side. The weevil on the left is red and the weevil on the right is gray.

Differentiating Two Species of Sunflower Seed Weevils

While scouting sunflower, there are two types of seed weevils that you may encounter. They are the red sunflower seed weevil and the gray sunflower seed weevil. It is possible to observe both of these species on a single sunflower head.

Red-brown colored weevil with bent antennae originating on the elongated mouthparts.

Watch for Red Sunflower Seed Weevils

In South Dakota, sunflower flowering is well underway. That means it is time to start scouting fields for red sunflower seed weevils. During the last two years, red sunflower seed weevil populations have been higher than normal with areas that exceeded the thresholds by as many as 300-500 adults per sunflower head.

Sun rising over a vast spring landscape with green corn emerging from the soil.

Ag Economic Dialogues Scheduled

August 15, 2019

SDSU Extension will focus on production and marketing decisions at the August and September Ag Economic Dialogues.

Markets/Prices, Corn, Field Pea, Flax, Oats, Oilseed, Pulse Crops, Sorghum, Soybean, Sunflower, Wheat, Economics

Close-up of several black caterpillars feeding on a green sunflower leaf.

Checkerspot Caterpillars in Sunflower

While scouting sunflower near Sturgis this week, we came across outbreak levels of checkerspot caterpillars that were defoliating the plants. Similar sightings have been reported throughout Western and Central South Dakota in recent weeks.

A sprayer applying pre-emergent pesticide to a bare field.

Herbicide Rotation Restrictions

This is a quick reference guide to common herbicides and their rotation restrictions for selected crops.