Issue No. 12/June 15, 2007
ALERT:Get Ready for Japanese Beetles and Western Corn Rootworms
Record numbers of Japanes Beetles are being caught in traps in southern Illinois. Also, it seems that an earlier prediction that western corn rootworm beetles will emerge earlier than usual has come to fruition.
Hot, Dry Pattern Persists Over East-Central Illinois--Good Survivorship and Early Emergence of Corn Rootworm Adults Expected
Hot and dry conditions will speed up the larval and pupal development of many soil insects, including corn rootworms.
Accurate Identification of Western Bean Cutworm Moths Is Crucial
Moths other than western bean cutworm moths may be caught in western bean cutworm pheromone traps. Accurate identification is critical.
Japanese Beetle Numbers in Southern Illinois Are Already Alarming
Some corn in deep southern Illinois is almost ready to tassel, and many Japanese beetles can be found in the whorls. The big concern is the beetles' propensity to clip silks.
Soybean Aphid Numbers Small in Illinois, Unusually Large (This Early) Elsewhere
Given the unusually large numbers of soybean aphids in relatively young plants being found to the northeast of Illinois, everyone in northern Illinois should be examining soybean fields right now for soybean aphids, among other pests.
Short reports are provided on European corn borers, grape colaspis, white grubs, burrower bugs, and twospotted spider mite.
Time to Sample for Nematodes in At-Risk Corn Fields
Producers should be sampling for corn nematodes, especially in corn fields with risk factors: corn-on corn, minimal or no tillage, and the absence of nematode-suppressing soil-applied insecticides.
Request for Waterhemp Samples
A rapid assay is being tested as a diagnostic tool for confirming PPO resistance in waterhemp. Input is sought from anyone who suspects having a resistant waterhemp population.
Postemergence Herbicide Applications in Soybean: Pull the Trigger or Wait for Rain?
Suggestions are offered about whether to make a first postemergence application of glyphosate in soybean despite dry soil conditions.
Alfalfa Crown Rot: Time to Renovate or Rotate?
Symptoms along with scouting and control recommendations are described for alfalfa crown rot.
Soybean Disease Update
Short reports are provided on root rot and damping-off, leaf spots, and soybean rust.
"Good" Stress or "Bad" Stress?
How dry weather affects corn and soybean development and yield is discussed.
Reports are provided this issue for northern, southern, and west-central Illinois.