Plant and Insect Diagnostic Clinic Update - April 9, 2008

We have received several samples from evergreens showing symptoms of "winter browning." Winter browning results from a combination of freeze/thaw cycles, rapid temperature changes, and cold temperatures as evergreens continue to lose water as they photosynthesize over the winter. See the Horticulture and Home Pest News March 8, 2006, for more information.

We received two interesting galls. Western pine gall rust is a fungal disease that causes round galls on branches of Scots pines. See this week's article.

Many wasps form galls in oaks, especially shingle oaks. We received a large gouty oak gall from a shingle oak (see picture below). See Extension bulletin IC407 for information on insect galls

We have been receiving samples of wood cockroaches. These cockroaches live outdoors, but warming temperatures cause them to wander. Please see our Insect Information Notes for more information on wood cockroaches.

Speaking of warmer weather, I am starting to notice more multicolored Asian lady beetles crawling around my windows. These are beetles that have been overwintering in my house since fall. Homeowners can also expect to see boxelder bugs crawling about as well if they had had high populations last fall. These insects did not reproduce in the walls. They have just been waiting for warmer weather.

Gouty oak gall.  (Photo by Christine Engelbrecht) Gouty oak gall. (Photo by Christine Engelbrecht)


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