–by Dr. Jeff Whitworth — Field Crops
Most alfalfa around north central Kansas, has been swathed at least once and some fields even twice. Adult alfalfa weevils were very common in many fields up until about 10 days ago, which caused considerable concern. When temperatures finally approached and/or exceeded 80-85 °F, however, most adults migrated out of the fields and should not cause any more concern, or return in large numbers, to alfalfa fields, until September. Adult alfalfa weevils do feed just a little-but not anywhere as voraciously or as long as the larvae (see pic 1-alfalfa weevil larva noted still in the field on 8 June, 2021)
Picture 1 Alfalfa weevil larva
Picture 2 Grasshopper Nymph
Very few actual pests have been noted in alfalfa fields over the last couple of weeks. However, grasshoppers are hatching and these small nymphs (see pic 2) should be closely monitored. Adult leafhoppers have started migrating back into the state so as fields start to grow back after cutting these should be monitored also. Fortunately, there seem to be good numbers of lady beetles (see pic 3-lady beetle larva; pic 4-lady beetle pupa; and pic 5-adult- -this adult has the neatest name in entomology in my opinion–twicestabbed lady beetle) which should help control any aphid problems going forward.
Picture 3 Lady beetle larva
Picture 4 Lady beetle pupa
Picture 5 Lady beetle adult (Twicestabbed lady beetle) – two distinct red spots on their back
(All Photos by Cody Wyckoff)