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Content by Eric Jones

A group of green plants with white seed heads amongst green grass.

Avoid Noxious Weeds When Haying Right-Of-Way Ditches

After June 15 or July 10 (dependent on location), right-of-way ditches can be mowed or hayed as announced by the South Dakota Department of Transportation. While there is a demand for grass hay, care should be taken when haying right-of-way ditches.

Sunflowers blooming in a South Dakota Field.

Sunflower Production: Late-Season Weed Escapes Should Guide Future Weed Management Plans

Many sunflower fields across the state are far enough along in their development that the window for preventing weeds with residual herbicides has passed. Weed escapes that remain in the field through the remainder of the growing season can contribute seed back to the soil seedbank.

Green soybeans plants with a light grey background. All soybean plants have purple flowers which indicates the plants have reached reproductive stage 1.

Soybean Plants Are Entering the Reproductive Stage (R1): Last chance to spray select herbicides

The summer solstice roughly marks the date when soybean plants switch from vegetative growth to reproductive growth. An important aspect of the reproductive growth stage is that many herbicides can no longer be applied after plants reach any bloom stage.

: Two photos with various plants that are brown, yellow, and/or green. A blue pen is in the foreground of each photo for size reference.

Clock tells the time of the day, not when the job is done. Is that true for weed management?

Common banter at the farm gate implies farmers work long days to get the job finished. However, weed management may improve if spraying stops at a particular time of day.

Aerial view of the SDSU Northeast Research Farm.
Jul 23

Northeast Research Farm Tour

Attend the annual Northeast Research Farm Tour on Thursday, July 23, 2026, from 4:00 p.m. CDT to dusk at the Northeast Research Farm (15710 455th Ave. South Shore, SD 57263). The farm is located on the junction of State Highway 20 and Codington County Highway 11, or 2.5 miles west of Exit 193 on I-29.

A red, weed hoe next to a freshly cut, green weed surrounded by brown soil.

Reminder: Cutoff for over-the-top dicamba products labeled for soybean is June 30 or R1 growth stage in South Dakota

Over-the-top dicamba products for application in soybean have been relabeled for the 2026 growing season. A stipulation for applying these herbicides is a cutoff date of June 30 or R1 soybean.

Multiple weed species growing in a grassy area.

Noxious Weeds Should Be Closely Monitored for Management

Pasture, rangelands and rights-of-way are starting to turn yellow, purple, or even a mix of both due to rapid growth of noxious weeds. Now is the time to implement management tactics to ensure the weeds do not outcompete desirable vegetation and invade adjacent land.

Wind carrying a cloud of topsoil over a dry, bare field.

2026 Growing Season: Forecasted dry weather and the implications on postemergence herbicide activity

Weather cannot be controlled, but there are variables we can control to help increase the effectiveness of postemergence herbicides during drought conditions.

Picture of mostly brown soil with two, small, faintly green plants near the center.

Waterhemp Has Emerged in South Dakota

Waterhemp seedlings were observed in Volga, South Dakota and other observations of emerging seedlings have been and reported elsewhere in the state. While the seedlings are still small, forecasted rain and increased temperatures will cause these plants to grow rapidly.

Young absinth wormwood, Canada thistle, and leafy spurge plants emerging.

Start Management Plans Now: Absinth wormwood, Canada thistle and leafy spurge have emerged and are starting to grow

Absinth wormwood, Canada thistle and leafy spurge have emerged and are growing in eastern South Dakota. If not effectively managed, these weeds can displace desirable forage in pasture and rangeland.