Late Summer is Right Time to Attack Magnolia and Tuliptree Insects, says IAA

ANTIOCH, IL, August 18, 2010 (Press-News.org) August and September are good months to control many of the insects - called "scales" - attacking woody trees and shrubs throughout the state, says Illinois Arborist Association (IAA) President Bill Bolt, a Springfield, Ill.-based consulting arborist. Two trees most affected by scales are Magnolias and Tuliptrees, which may seem to be raining a sticky fluid.

"The syrup-like fluid is actually honeydew - a result of insect feeding by a scale measuring up to one-half-inch in diameter," Bolt said. "This year we have seen one-to-two year old magnolia branches covered with this pest." Magnolias commonly attacked are the Star, Saucer, Cucumbertree, and Lily Magnolias.

The honeydew can attract a black sooty mold fungus which covers leaves and twigs attracting ants and bees. Other symptoms include small leaves, stunted growth and poor flower production. In late summer the mature female turns pinkish orange to dark brown. Late August and early September are prime times to control the pest during the crawler stage. Crawlers are gray/reddish brown and easily spotted on the underside of branches.
Tuliptree scale is another insect producing large amounts of honeydew and sooty mold fungi.

Host plants affected by this pest are Tuliptree, Magnolia, Basswood, Linden, Redbud and Walnut. Adult females are easily spotted this time of year. They are a large, convex scale, orange with black mottling.

"Heavy infestations of this scale may kill small trees," Bolt said. "Live crawlers, red in color, are produced this time of year. As many as 3,000 crawlers per female are possible. The crawler stage is a good time to control this pest."

Contact a certified arborist for proper timing and the best control methods available to combat these scales. To locate a certified arborist in your area, contact the IAA at (877) 617-8887 or visit http://www.illinoisarborist.org.

Illinois Arborist Association background
The Illinois Arborist Association is a non-profit organization that educates members and the general public in proper tree care. IAA supports research on trees and is based on the mission to "Foster interest, establish standards, exchange professional ideas and pursue scientific research in Arboriculture."