Spring seems to be on the way! Temps around Chicago are struggling to get out of the 40s, but soon enough warmer temps will be here and we must look to checking our trees.
In springtime, it’s a good idea to keep an eye on your trees for traces of troublesome insects that can cause problems as we move into warmer weather. Experts from Morton Arboretum tell us three kinds are especially pesky: gypsy moths, Zimmerman pine moths, and bagworms.
Gypsy moths leave egg masses on the lower 20 feet of the trunk and the underside of the lower branches. The masses are tan to yellowish brown, are less than an inch wide, and about an inch and a half long. Scrape them off carefully and try not to remove too much bark. They can trigger allergic reactions so wear gloves and a face mask if you have severe allergies. Just plunge them in a bucket of soapy water to kill them and pour some soapy water on the affected area. Mild soapy water is a great organic insecticide as it will not harm plants but suffocates insects.
Zimmerman moths tunnel into Austrian and Scots pines and feed under the bark. They can weaken branches, which then die or break off in the wind. The larvae are almost impossible to see. If you see any white or pinkish pitch dripping, you probably have an infestation. Keep your pines healthy; they are attracted to stressed trees. You can apply insecticide to the bark and needles in April and August.
Bagworms are usually found on junipers and arborvitae. These caterpillars feed on needles and leaves in the summer then form them into bags that hang down resembling pinecones. They are smaller, about 2.5 inches long. The problem is that they hold about 1,000 eggs to perpetuate the next generation. It’s easier to see them before trees leaf out. Cut them off well before June when they will hatch.
See images and obtain other info at www.mortonarb.org. Click on “Trees and Plants”, then click “Help with Pests”.
KATHLEEN WEAVER-ZECH & DEAN’S TEAM CHICAGO