By Rebecca Vittetoe
Most of Iowa received some amount of rainfall this last week with totals ranging from a trace to over 4.5 inches in parts of southwest Iowa. Unfortunately, with that rain, there were also some strong winds, hail, and tornados. In addition to some crop damage from the storms, concerns about the drier conditions in northwest Iowa, late season weed flushes, corn aphids, rootworm beetles, and crop diseases were other topics of conversation this past week for ISU Extension field agronomists. Read on for more specifics about what’s been noted in fields across the state.
Leah Ten Napel (Region 1)
“Crops across northwest Iowa look generally good, although rainfall has been variable across the region. During the Aug. 3 – 9 reporting period, many areas received around 0.75 to 1.50 inches of rain, with some locations receiving considerably less and others picking up heavier amounts from localized thunderstorms. The recent rainfall was beneficial, but the variability means moisture conditions can look very different from one field to the next. Corn is progressing rapidly through the dough stage and into dent. At this point in the season, adequate soil moisture remains important for maintaining grain fill and maximizing kernel weight. Fields that have received timely rainfall should have good conditions for continued grain fill, while areas that missed recent storms will need to be monitored for increasing moisture stress and premature plant senescence. Soybeans are also moving through an important reproductive period, with most fields setting pods. Adequate moisture during pod development and seed fill will be important for protecting yield potential. Continue scouting for soybean diseases, particularly in fields with dense canopies and frequent moisture, is warranted. Insects should also be monitored as crop development continues. Diseases may still develop or spread with additional moisture, but there would likely not be a ROI with an additional fungicide application at this point in crop development. Overall, crop conditions across northwest Iowa remain fairly positive, but rainfall variability continues to be something to watch. The next couple of weeks will be important for corn grain fill and soybean pod and seed development. Where soils are beginning to dry, additional timely rainfall would be beneficial as the crops work to finish out the growing season.”
Source : iastate.edu