Scouting By Brian Banks, Senior Agronomist
Overall, this season has not seen any major concerns with disease or insect infestations across the Corn Belt as a whole. It is, however, that time of year to be scouting for the following issues in corn and soybeans.
Western bean cutworm (WBC) moths are currently being trapped and numbers are increasing. Scouting should be done for egg masses and larvae now, and then continue until about a week after the peak moth flight. WBC eggs take roughly a week to hatch and the larvae will feed on leaves and pollen before making it to the ear to feed on silks and kernels. There is a relatively small window of opportunity to kill the eggs or larvae before they reach the ear and are then protected by the husk. Check with local universities for moth trap numbers and treatment threshold levels. Other insects on the increase in corn at this time are corn earworm and western corn rootworm beetles. If an insecticide treatment is warranted, consider a tank mix application of OverPass CF, Super 72, or Phosfix.
Soybean aphids are a pest that will typically be scouted for in late July and into August but South Dakota State University has reported finding populations that are increasing in the eastern part of the state. Because of warmer than average temperatures this winter, soybean aphids may reach economic threshold levels earlier this year. Other insects to be scouting for at this time are Japanese beetles and bean leaf beetles. These insects may not reach threshold levels independently, but if all are found in a field, an insecticide application may prove beneficial. If applying an insecticide, consider tank mixing OverPass SF, Phosfix, or Bean Maker. CLICK HERE for more information.
The most recent crop progress report shows soybeans that are blooming or setting pods are both just above the 5 year average. Soybeans in good/excellent condition are at 62%, which is down from the last report and well below the last few years as shown in Figure 1. Corn in good/excellent condition is at 65% which is down from the previous report and is well below the last few years, shown in Figure 2. Corn silking is at 19%, which is behind the 5-year average of 27%. Weather predictions for July 17-21 (Figure 3 & 4) show a high probability of above average temperatures and below average precipitation. With a lot of corn just beginning to silk, these are not the best conditions. This is why it is important to have a well-planned fertility program in place early to maximize plant health and development, giving plants a better chance to maximize yield in adverse conditions.
Hot, dry conditions will speed up pollination, pollen will drop for a shorter period of time. These hot, dry conditions also impact silk development. Silks from the butt of the cob emerge first and from the tip last. If pollen drop is hastened by weather conditions, it is possible to have poor kernel fertilization, resulting in blank ear tips. Modern hybrids will typically be silking at the same time as tassel emergence so that pollination can be successful even when hot, dry conditions exist. CLICK HERE for an in-depth explanation of tasseling, silk development, and pollination written by Bob Nielson from Purdue University.
Figure 3 & 4:
Graphics from National Weather Service, Climate Prediction Center.
Research Trials By Amy Schroeder, Research Agronomist
HARNESS THE POWER OF THE ANDERSONS MICROSOLUTIONS® MICRONUTRIENTS —
Summary: In 4 replicated plots across the nation, Phosfix applied at V6 has resulted in an average yield increase of 5.22 bu/A. Yield was improved by enhancing crop vigor and encouraging crop health.
These photos were taken in the same Ohio field on 7/27/16. The soybeans were at the R3 growth stage. The treated plot, pictured on the right, received a foliar application of Phosfix at the V6 growth stage. A 5.2 bu/A yield increase over the check, pictured on the left, was observed in this replicated testing.
Phosfix is a 7-4-9 with micronutrients and trace amounts of humic and fulvic acids. Phosfix improves yield by enhancing crop vigor and encouraging crop health. Phosfix is designed for use on all crops and helps plants recover from environmental stress. Early application enhances seed set and fruit fill.
Phosfix can be applied to a variety of field and row crops, vegetable crops and fruit. The recommended application rate is 1-2 pt/A. Phosfix can be applied at a variety of post-emergence timings.