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Crop Treatments

All Crop Treatments Content

Young sunflower plants emerged in a vast field.

Overlapping Residual Herbicides May Be Necessary for Effective Weed Management

Weed management in sunflowers poses unique challenges. Compared with many other crops, there is a limited number of herbicides selections, especially postemergence herbicides.

Adult red sunflower seed weevil on a sunflower leaf.

Malathion receives special local needs approval to treat red sunflower seed weevils in South Dakota from July 15 to August 31, 2025

The request was submitted and approved by the Environmental Protection Agency due to the large populations of red sunflower seed weevil present in South Dakota that are resistant to pyrethroid insecticides.

A black ink pen lain next to small, green and red waterhemp plants with a brown, dirt background.

Waterhemp Has Emerged in South Dakota: Time to prepare for post-emergence management

Waterhemp has started to emerge across South Dakota. While waterhemp plants are small now, recent rain events and forecasted warmer air temperatures are ideal for waterhemp growth.

Two small, green soybean plants with brown to yellow coloration on their leaf edges, indicative of herbicide damage. Tan sand and yellow fertilizer pellets are in the background.

Wind and Rain May Have Delayed Preemergence Herbicide Application: What Now?

With recent winds and rain, preemergence herbicide applications may be further delayed. Scouting to determine if crops and/or weeds have emerged is critical to ensure effective and safe application of preemergence herbicides.

Corn plants and scattered weeds emerge from a dry, no-till field.

Dry Conditions May Hinder the Performance of Recently Applied Preemergence Herbicides

If a preemergence herbicide does not receive an activating rainfall, generally 0.5 to 1 inch of rain, many weeds will emerge, as the herbicide remains on the soil surface.

Farmer inspecting a no-till field before planting.

Early Preplant or Preemergence Applications for Weed Management in Corn: Which is better?

Preemergence herbicides should be a part of a successful weed management plan, as these applications limit the amount of early-season weed interference to limit yield loss and reduce selection pressure on herbicide-resistant weeds.

Atrazine carryover injury to eastern redcedar seedling

Herbicide Carryover and Planting Bare-Root Tree Seedling in New Windbreaks

Guidelines on herbicide carryover when planting bare-root tree seedlings in new windbreaks

A red sprayer in a green field with a cloudy sky in the background.

How to Stop Drift

The goals of applying any crop protection products include: increasing effectiveness, mitigating drift, and maximizing profits. We will focus on mitigating drift, even though all three interact with each other.

Two scans of older SDSU Extension publications from 1949 and 1959.

Revisiting Old Lessons in Corn Weed Management: 2,4-D and dicamba

What can past herbicide programs teach us about managing against herbicide-resistant weeds in corn today?

Group of farmers strategizing near a field at sunset.

Now is Time to Plan Your Weed Management Strategy for the 2025 Growing Season

As harvest season comes to an end, now is the time to start formulating your weed management plan for next year. Learn some expert tips for getting your operation off to a good start next growing season.