The April 13 South Dakota NASS crop progress report indicates that spring wheat planting was at 27% completion, near the five-year average of 16%, and oats were at 35% planted, ahead of the five-year average of 17% by this date.
In addition, winter wheat condition was reported as 10% very poor, 30% poor, 38% fair, and 22% good, and 0% excellent (nass.usda.gov) this likely reflects the dry fall and winter many parts of South Dakota faced. While progress continues, many parts of the state are looking for moisture.
As it begins to warm up, considerations for a crop pest control and soil fertility plan come to life. One major factor that producers can control is applied fertilizer needs. I like to revisit the term yield goal each year, as I often find that its meaning is widely misunderstood.
Many think of yield goal as what we hope to see a crop produce this year. However, by technical definition, yield goal actually describes yield history, while taking into consideration potential for improvement. It is best to use five to 10 years of yield history when developing a yield goal. Outliers from years with abnormally low or high yields should be excluded; being realistic yet optimistic is always important.
Some suggest adding an additional 5-10% above your average yield history to account for improvements in production from year to year, or you can take your average yield factor times a range from 1.03 to 1.07 to account for increasing yield potential. However, adding to the average yield figure should be omitted during years when drought or other major crop stressors are confidently predicted. It is also common practice to create yield goal values for fields or groups of fields with similar soil properties and topography within a farm. If one field varies quite significantly in soil physical properties from its neighboring fields, calculating separate yield goals is crucial; however, if the fence line seems to be the only major difference, an average across fields is likely appropriate.
Many decisions are made based upon yield goal; fertilizer applications being one of the most important. The South Dakota Fertilizer Recommendations Guide was developed with yield goal in mind, making proper yield goal calculations even more important. This publication provides well-researched soil fertility guidance for all common South Dakota field crops in a user-friendly manner. To find a copy of the guide, visit extension.sdstate.edu and search fertilizer recommendations guide.
As planting has begun in some areas, herbicides should also be moving to the top of mind. Know your fields and the weeds that you expect to find in them. Of course, scouting is always necessary, but having an idea of what weeds to expect can help a great deal when trying to create or revise a herbicide plan. One big factor that can easily be overlooked when planning spring herbicides is temperature.
The following information is a summary of an article written by my colleagues, Eric Jones, Philip Rozeboom, Jill Alms and Dave Vos. Many burndown herbicide labels state to apply when temperatures are above 55F, but temperatures sustained at 60-70F for several hours after application are more ideal for greater chemical activity. The main reason behind this is plant growth. When its cold, plants are not as actively growing as under warmer temperature conditions. Active growth allows herbicides to translocate or inhibit targets sites, increasing weed control.
It’s not uncommon for spring daytime temperatures to be ideal but night temperatures to be close to or below freezing. If some weed tissues freeze and die, herbicides may have poor control. Therefore, its best to wait until night temperatures are sustained around 50F for several days after application.
If temperatures or precipitation are delaying you and weeds are becoming an issue, there are some modifications that can help increase control under less-than-ideal conditions. One option to maintain herbicide performance is to increase rates (within the labeled rate) on some products. Another option may be to consider mixing two different herbicides per label instructions, this practice of mixing modes/sites of action often results in more consistent control when compared with applying an individual product. Perhaps the simplest option is to increase sprayer output; by doing so you can increase coverage to ensure the highest ideal amount of herbicide is being intercepted by the plant. All of these options may help, but the most effective measure to increase herbicide activity is to wait for ideal conditions.
See the 2025 South Dakota Pest Management Guides (and your herbicide label(s)) for assistance in making informed pesticide application choices this year. To receive a hard copy, visit your nearest SDSU Extension Regional Center or request copies be mailed to you by filling out a form here. To view/download electronic copies visit extension.sdstate.edu and search Pest Guide.
Upcoming events
- April 28: Free screening of World Without Cows at Brookings. Visit extension.sdstate.edu/events and to sign up by April 28.
- May 1: I-29 Moo University Forage Webinar Series 7-8:30 p.m. Sign up at no cost here.
- May 15: International Farm Transition Network Roadmapping Your Succession and Adding a Family Member to the Farm Business online training session. Sign up at extension.sdstate.edu/events.
- May 16: Ag Economic Dialogues free webinar at 10 a.m. Sign up at extension.sdstate.edu/events
Leave a Reply