Over the last month, I’ve heard quite a few people comment that they aren’t sure the old “knee high by the Fourth of July” adage will be true this year for their corn.
These last couple of hot weeks with scattered showers and storm events have made that concern diminish for most, but that’s not to say there aren’t some things to take care of yet this summer.
At this point in the growing season many producers are working on post-herbicide applications to row crops. Most winter wheat and oats have headed out and some are beginning to ripen quickly. Alfalfa growers in eastern South Dakota are working on their second cutting and many grass hay meadows across the state are being cut. With all of that happening, there are a few things to be aware of in your fields.
1. Watch for resistant weeds after spraying. If you find living plants that should have been controlled right next to dead plants, a spreading patch of plants of a particular species that should have been controlled, or surviving plants mixed with controlled plants of the same species, this is likely due to some level of herbicide resistance. We definitely don’t want these plants going to seed and spreading the issue further, so be sure to effectively control escapes.
2. Scout for insects, especially in oats and wheat. True armyworms have been spotted early this year in oats near Beresford.
This caterpillar feeding can reduce yields, especially if the flag leaf is removed before soft dough stage. You can scout individual plants using a threshold of two caterpillars per square yard, or if using a sweep net- 40 caterpillars per 30 pendulum sweeps.
For further details on scouting and managing this pest, see the latest pest and crop newsletter at extension.sdstate.edu.
3. Watch for Fusarium head blight (scab) in spring wheat; this disease can occur in wheat at flowering, causing reduced yields and accumulation of mycotoxins.
Fungicides should be applied during flowering/prior to infection to be effective; the ‘Scab Prediction Tool’ (http://www.wheatscab.psu.edu/) can be a very helpful guide to pre-determine if your wheat is at risk.
4. Other wheat diseases may pop up in fields; however, flowering is the last growth stage to effectively apply fungicides in wheat.
Even if it’s too late for a fungicide application this season, it is good practice to scout fields and know what’s out there for future reference; disease resistant varieties are typically a wise investment, and remember that fungicides can be applied proactively.
Upcoming Events and Announcements
• The South Dakota pesticide container recycling dates and locations have been released. The SD Deptartment of Agriculture offers a free pesticide container recycling program in various locations across SD.
Containers should consist of high density polyethylene plastic of 2.5 gallon size or less, be triple rinsed, contain no visible pesticide residue, contain no more than .5 fluid oz. of clear water, and still have labels on the jug if possible. For more details and a listing of dates and locations, visit sdda.sd.gov/ag-services/pesticide-program. If you would like to recycle a large bulk container, contact the SD Dept. of Ag for more info at 605-773-4432.
• Plot Tours at SDSU Winter Wheat Crop Performance Testing (CPT) sites are being hosted “open house” style this year from June 26- July 27. Each winter wheat CPT trial contains plot signage and a document box for anyone interested in a self-guided tour! The trials are located near: Brookings, Hayes, Onida, Pierre, Selby, Wall, and Winner. For location details on the plot nearest you visit extension.sdstate.edu/events.
• SDSU Virtual Field Day Events. This year, the South Dakota Ag Experiment Station will host research farm tours online due to health concerns surrounding COVID-19. Farm managers, researchers, and Extension personnel have prepared recordings and documentation for anyone interested. The Southeast Research Farm held live online Zoom session on July 7. To view a recording of the Dakota Lakes Research Farm tour held in June, visit dakotalakes.com. Other virtual farm tours will be happening soon.
• SDSU Extension is collaborating with Michigan State University Extension in conducting a research study to learn more about the struggles farmers experience and what types of information may help. If you would be willing to take a one-minute survey to determine eligibility please go to the SDSU Extension Agronomy Facebook page to find more details.
• SDSU Extension is hosting free weekly Pest and Crop Q&A webinars each Thursday at noon CDT.
Visit extension.sdstate.edu/events for details of each week’s webinar.