Recently SDSU Extension held their annual Wheat Walk program on May 25 and June 1, 2017. The Wheat Walk programs brought producers, Industry and SDSU Extension experts out and into wheat fields near Pierre, Wall, and Clark. The SDSU Extension Wheat Walks were funded by the South Dakota Wheat Commission. Depending on which location you attended, breakfast, lunch or dinner was made possible to each attendee at each session, courtesy of SD Wheat Inc. Wheat Walk attendees learned valuable and timely information but most importantly those that attended were able to get their questions answered. Certified Crop Advisor continuing education credits were available for those who needed them. All topics were addressed at each Wheat Walk location with the exception of the Pierre and Wall location where additional plots and topics were observed and discussed.
Evaluating Wheat Stands & Assessing Yields
Agronomic issues discussed were how to properly determine the wheat growth stage and how to evaluate wheat stands which included a discussion on yield assessment. Discussion also involved the cold temperatures, frost damage, and variety selection. Majority of the winter wheat in the area was at heading (or very close to it) and flowering stages. The spring wheat was at late tillering to early jointing stages.
Wheat Disease Management
Emmanuel Byamukama (SDSU Extension Plant Pathologist) and Connie Strunk (SDSU Extension Plant Pathology Field Specialist) led the plant pathology discussion which focused on identifying wheat diseases and their life cycles, how to manage diseases using cultural means, and using IPM strategies to determine when a fungicide intervention becomes justified. Also discussed were the different tools available to growers and consultants to aid in fungicide application decisions. Diseases observed (depending on location) during the Wheat Walks were stripe rust, wheat streak mosaic, barley yellow dwarf, tan spot, and powdery mildew. Stripe rust was found at very high levels at one location near Clark. This fungal disease can quickly become yield limiting when found at high levels. If the infection affects the flag leaf, yield reductions can be as high as 50%.
Wheat Disease Management Tools
The SDSU Climate and Weather Center hosts the small grains disease model for the prediction of Fusarium Head Blight (FHB), tan spot, leaf rust, and other leaf spot diseases. The National Fusarium Head Blight Prediction Center also has an online and mobile tool that estimates the likelihood of FHB development in wheat.
Adam Varenhorst (SDSU Extension Field Crop Entomologist) stressed the importance of scouting for insects and using established thresholds when making insecticide management decisions. Following IPM strategies helps maintain the populations of beneficial insects in wheat that often include numerous insect predators, which can make insecticide applications unnecessary, save input costs, and avoid putting pesticides into the environment when they are not needed. Discussion also focused on the English grain aphid and aster leaf hoppers that were observed in many of the locations involved in the Wheat Walks. Other pests included brown wheat mites, wheat curl mites, and a reminder to scout for true armyworms prior to harvest.
The soil fertility discussion led by Anthony Bly (SDSU Extension Soils Field Specialist) and David Karki (SDSU Extension Agronomy Field Specialist) focused on wheat grain yield and protein relationships. High yield wheat generally has low protein while the opposite is true for low yielding wheat. Supplemental nitrogen above standard recommendations for the yield goal are necessary for increasing the grain protein of high yielding wheat. While foliar sprays after pollination have shown to increase NIR grain protein, baking quality factor improvement has not been seen in a limited research evaluation. Supplemental nitrogen application for enhancing grain protein should be applied prior to boot stage in order for precipitation to take the N into the soil, be converted into plant available forms and absorbed by plant roots.
SDSU Extension W.E.E.D. Project
Paul O. Johnson (SDSU Extension Weed Science Coordinator) identified weeds observed at each location. He talked about managing cheat grass. He also shared that the W.E.E.D project will continue to evaluate herbicides used in new ways and will continue to focus their research on herbicide resistant weeds.
At our Pierre Wheat Walk, Dwayne Beck (Dakota Lakes Research Farm Manager) discussed rotations. Ruth Beck (SDSU Extension Agronomy Field Specialist) discussed current field scale research on the use of molasses with foliar N (UAN) and liquefied urea applications on wheat.
At the wheat walk in Wall, Chris Graham (SDSU Extension Agronomist) discussed wheat varieties and noted susceptibility of various diseases, most notably wheat streak mosaic, by variety. He also discussed the purpose of the new Haney Soil Test and discussed ongoing research to evaluate the accuracy of this test to predict nitrogen needs in winter and spring wheat. Finally, he presented results from a 3-year study on the value of split-applying nitrogen in winter wheat and demonstrated the visual effects of nitrogen deficiency through demonstration plots.
2018 Wheat Walks
Plans are underway to continue the Wheat Walks in the Spring of 2018. The Wheat Walks just keep getting better and better and provide an opportunity for hands-on, face-to-face information sharing amongst SDSU Extension, wheat growers, and agronomists.