Volume 62 Number 18 Date 08/31/2017
LATE BLIGHT - Potato and tomato growers are advised to continue protective fungicide treatments and monitoring plants for signs of infection. Development of this disease has been confirmed by the UW on tomato in five counties (Dane, Kenosha, Jefferson, Pierce and Waukesha) and on potato in three counties (Iowa, Portage and Waushara), though late blight is likely to be more widespread given favorable weather conditions throughout August.
SQUASH BUG - Egg deposition is still occurring in home gardens and larger plantings. Several fresh egg masses and many small nymphs were found this week on acorn squash in a La Crosse County, emphasizing the need for thorough fall clean-up of garden debris to reduce populations and eliminate winter hibernation sites. Crop rotation is also suggested if squash bugs have been a problem this summer.
FALL ARMYWORM - Low numbers of this late-season pest were registered in the Janesville black light trap in the past week. Fall armyworm moths seldom arrive in Wisconsin in damaging numbers, but the larvae occasionally appear in corn where they can be mistaken for the corn earworm. Fall armyworm larvae have a lateral stripe and are usually light brown or black in color, whereas the corn earworm larva may be green, yellow, pink or tan.
-- Krista Hamilton, DATCP Entomologist