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Fruits
Volume 60 Number 1 Date 04/23/2015 SPOTTED TENTIFORM LEAFMINER - The first of three flights expected this season began by April 10 in southern Wisconsin. The apple orchard near Hillpoint in Richland County reported 450 moths this week, which is considered moderate for this apple pest and suggests peak emergence (or peak trap catch) of spring adults is approaching. This event can be anticipated at advanced sites during the first or second week of May. GRAPE FLEA BEETLE - The spring migration of overwintered beetles into vineyards from nearby wooded areas and fencerows has started. Scouting twice weekly for this insect is critical from bud swell until the first leaf separates from the shoot tip, and may be discontinued once shoot growth has reached three inches. Early spring feeding by adult flea beetles damages primary buds, preventing shoot expansion and ultimately reducing grape yields. Plants on the margins of vineyards are at greatest risk of injury. An economic threshold of 5% of buds damaged should be used to determine the need for control. BROWN MARMORATED STINK BUG - Adult specimens have been collected from six Dane and Milwaukee County locations so far in 2015, nearly double the number of reported cases in the previous two years combined. The increase in BMSB sightings may be due to generally warmer weather than in the last two years favoring early spring activity from overwintered stink bugs. Since the first 2010 detection of BMSB in Wisconsin, there have been 25 confirmed reports from 10 counties. Sixteen of the reports involved specimens that were found indoors or inside structures (vehicles, shipping boxes, etc.), another seven cases were of specimens found outdoors, and two reports lacked collection information. Most of the outdoor stink bug detections were made in Dane County, where reproducing populations are suspected. This species has now been detected in 42 states and two Canadian provinces, posing severe agricultural problems in six states and nuisance problems in nineteen others. REDBANDED LEAFROLLER - Reports indicate RBLR moths began appearing in pheromone traps earlier than STLM moths this month, opposite of the usual emergence sequence. Counts since mid-April have ranged from 0-183 per trap and the first peak flight has not yet occurred. The RBLR degree day model forecasts this early-season event for 200 degree days (simple base 45°F). The accumulation at Madison was 137 degree days as of April 22. SPOTTED CUTWORM - Nocturnal feeding by this cutworm and other climbing species can be especially damaging to grape vines during bud swell. Scouting for cutworm activity is recommended through mid-May, particularly for vineyards on light, sandy soils where the risk of cutworm infestation is greatest. -- Krista Hamilton, DATCP Entomologist 
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