Most crop producers in Nebraska are in the midst of harvest now, and planning for next year is not on top of their “to-do” list. However, as harvest wraps up, soil sampling should be near the top of their list. This has been among the most challenging growing seasons in 50 years, with rainfall amounts far below average. Irrigation has moderated drought impacts for many Nebraska growers, but at a significant cost. The combination of drought conditions, heavy irrigation and widely varying yields means that soil testing is more important than ever this year.
In a recent CropWatch article, Grassini et al. noted that irrigated corn yields across Nebraska are predicted to be moderately lower (3-8% below average), while dryland yields will be substantially reduced (32-67% below average). These estimates are based on weather data from 2012, and assume no yield-limiting factors other than temperature and solar radiation for irrigated production. Many areas of Nebraska had high temperatures during pollination, which may further reduce yield from modeled predictions. The big question is how drought will affect nutrient requirements for next year. The net effect of crop nutrient removal on soil nutrient availability will vary from field to field, and with locations within fields.