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Forages & Grains
Volume 58 Number 8 Date 06/20/2013 ALFALFA WEEVIL - Larval counts have begun to decline due to pupation and harvest of first crop alfalfa. Carryover of larvae into second-crop regrowth is common, although averages are below 0.5 per sweep and leaf tip damage is generally less than 20%. Most larvae are in the late instars and will pupate by early July. Routine scouting is suggested until the second crop is established or the weevil season has passed. POTATO LEAFHOPPER - Migrant adult populations are approaching the economic threshold of 1.0 per sweep for 8- to 11-inch alfalfa and warmer temperatures expected next week could cause an abrupt population increase. Counts for the period of June 13-16 varied from 0.1-0.7 per sweep, with the highest average (14 per 20 sweeps) found near Richland Center. Nymphs were noted this week in scattered fields as far north as Black River Falls. PEA APHID - This insect has become more numerous since early June and populations in the southern and central Wisconsin alfalfa now range from 0.2-6.7 per sweep. Dispersal of winged adults to peas has not been noted as of June 19. -- Krista Hamilton, DATCP Entomologist 
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