Different circumstances, same set of harvest challenges for Ohio’s corn crop

first_imgShare Facebook Twitter Google + LinkedIn Pinterest By Matt ReeseIn what has been a tale of two Ohio growing seasons, the state’s corn crop has seen a widely divergent set of challenges, but may have similar harvest challenges that need to be monitored closely this harvest season.While some northern corn suffered from delayed planting, excessive moisture and then dry conditions that could lead to stalk integrity concerns this fall, the lush growing conditions in the southern two-thirds of the state led to a nearly ideal early season for corn (and diseases).“From U.S. 30 south seems to have a lot higher incidence of gray leaf spot (GLS) compared to what I’ve seen in the north,” said Roy Ulrich, DEKALB Asgrow technical agronomist. “We had GLS start on corn a lot earlier than we have typically seen. Last year we really didn’t start to see GLS until the middle or end of July in southern Ohio. This year we started picking up GLS at the end of June or first of July — almost a full month ahead of last year. This wasn’t a big surprise because we had the heat and then we had all that rain in June so we had plenty of moisture to get GLS to sporulate, get inoculum on the plants and start infecting fields. It was probably the highest GLS pressure I have seen in my 9-year career. It was pretty aggressive.”As temperatures dropped off a little later in the summer it changed the corn disease dynamic.“We hit the end of July and early August and temperatures relaxed. We saw GLS slow down. It was still out there at high levels but now we have seen northern corn leaf blight (NCLB) pick up in some areas,” Ulrich said. “Disease pressure is a lot higher than what we typically see, but we still see differences as to how severe that disease pressure is within products and between fields based on how they lay and their rotation.”Those summer conditions will have an impact on harvest this fall.“Early disease pressure put stress on the plant from a photosynthetic standpoint so it couldn’t produce as much energy as it would like to and, when you couple that with the really high nighttime temperatures that increase respiration rates, the plant was burning more energy than usual. Those plants could have cannibalized some of their stalks early in the season trying to get enough nutrients to move to the ear for grain fill,” Ulrich said. “We have a scenario where we could have some stalk integrity issues going into the fall. Any of those fields with higher disease pressure are at higher risk because the plant wasn’t able to produce as much energy during grain fill. Then August completely flipped the weather pattern on us and the plants may not have cannibalized the stalks like they would have if the high temperatures would have continued.”Pest issues could also contribute to stalk concerns this harvest.“In corn-after-corn fields, it was easy to find corn rootworm beetles. Rotated acres are more hit and miss. In some rotated non-traited fields we definitely saw more beetles than we have in recent years, but other areas we didn’t see it,” Ulrich said. “The corn-after-corn fields were pretty much at economic levels this year, but those corn-after-soybean fields, I am not sure.”At this point in the season, to get the most out of the 2018 corn crop, it needs to be monitored statewide for stalk integrity and for any late introduction of ear rots. Harvest needs to be prioritized accordingly, for corn in northern or southern Ohio. This column was contributed by Ohio’s Country Journal for DEKALBlast_img

Leave a Reply

Your email address will not be published. Required fields are marked *