Integrated Crop Management News

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Fall Fertilizer Nitrogen Application

October 30, 2019

Fall nitrogen (N) fertilizer application continues to be popular for several reasons, including lower cost, time for application, equipment availability, often better soil conditions, and competing springtime field activities.

Crop Quality in 2019: Another Unusual Year

October 10, 2019
Fusarium on an ear of corn (left) and Pennicillium on an ear of corn (right). 

This year continues the chain of growing seasons with extremes and rapid changes beyond our long-term experiences. This made for periods of both stress and favorable crop growth despite the planting dates. Frost, potentially killing in the northern half of Iowa, is expected between October 11-13. USDA data indicate a wide range of maturity due to planting date, but the periods of hot weather scattered through September and early October may have reduced the potential for very high moisture corn and soybean. Variability will be the key issue to manage in 2019 corn and soybeans.

Phosphorus and Potassium Management for 2020 after a Year with Highly Variable Yields

October 1, 2019
Net returns to P or K fertilization of corn and soybean for different soil-test levels in many Iowa soils for shown prices

Very variable weather this season will result in variable corn and soybean yield within and between fields. Entire fields or portions of fields were planted later than usual or were not planted. This will result in variable removal of phosphorus (P) and potassium (K) with harvest. Reduced yields combined with continued low market values create uncertainty about P and K fertilization decisions for the 2020 season.

Fall Burndown Treatments for Winter Annual Weeds

October 1, 2019

The plentiful rain in September has provided ideal conditions for establishment of winter annual weeds, thus many no-till fields will have dense stands of these weeds going into winter (Fig. 1). The wetter springs we have encountered recently complicate getting spring burndown applications made in a timely matter.