Issue No. 6, Article 4/May 5, 2006
Cowpea Aphid Densities Diminish in Some Fields
Dennis Epplin, crop systems educator, Mt. Vernon Extension Center, reported on May 2 that cowpea aphid densities were declining in some fields. Dennis attributed some of the reduction in numbers to rainfall. Producers are encouraged to continue monitoring their alfalfa for aphids and alfalfa weevils in the coming weeks. The effectiveness of natural enemies and early harvest in many areas may eliminate the need for any rescue treatment. Let us know if aphid numbers once again begin to increase in your area of the state. As we progress through May, we will need to monitor the regrowth of alfalfa following the first cutting for insect injury. Within a few weeks, don't be surprised if potato leafhoppers begin to appear in a few southern Illinois counties. In most years, the potato leafhopper spring migration becomes noticeable in southern Illinois by late May. We'll let you know when we begin to receive reports of potato leafhopper infestations.
Cowpea aphid injury in alfalfa (courtesy of Dennis Epplin, Mt. Vernon Extension Center).