KSMU's Michele Skalicky met up with Missouri Department of Conservation urban forester, Cindy Garner, recently at the Springfield Conservation Nature Center to talk about diseases and insects that can affect trees. MDC will hold a tree pest clinic Tuesday, June 25, from 8:30 a.m. to 1 p.m. at the nature center, 4601 S. Nature Center Way.
Garner pointed to a hawthorn that has cedar hawthorn rust, which she said is common in Missouri. It’s caused by spores that infect the tree at the time it flowers.
"So, when a tree's flowering, it's receptive, open to receive pollen and/or giving off pollen, and in this case it's receptive to receiving these spores--these microscopic spores," she said.
These spores come from what Garner describes as “an orange ball of gelatinous goo,” or spore horns, which are found on cedars.
That’s just one tree problem that can be identified at the tree pest clinic. Take photos or infected branches at least 12 inches long with you for identification. If you plan to take the branch with you to work so you can attend the clinic on your lunch break, Garner suggests wrapping the end in a wet paper towel and putting it in a plastic bag or put the branch in the office fridge.
Some other common tree problems include jumping oak gall on white oaks, which Garner is seeing a lot of this year. This causes small galls on the underside of white oak leaves—each one containing a wasp larvae—and leaves to turn brown in late spring. There’s also oak wilt on red oak (according to Garner, insect and disease are usually specific to the species), cedar apple rust, bagworms, aphids and spider mites.
"The other one that often I receive a lot of calls about that they think is an insect is damage that's caused by the sapsucker, which you know is a member of the woodpecker family," she said. "And, everybody always thinks that it's an insect, and they want to spray, but it's not."
Sapsuckers peck on the tree, which causes the tree to produce sap, and the birds feeds on it, according to Garner. She’s heard from homeowners who’ve sprayed insecticide to try to treat the problem before they found out what it was.
"Often, people want to spray for whatever's going wrong or what they think is going wrong with their tree when they, after looking at it and figuring out or finding out the correct diagnosis, they could avoid using chemicals," said Garner, "and we just want to try to avoid that 'cause often it might be just that it's caused by a bird, not by an insect or a disease."
Some diseases and insect problems on trees are harmless, though unsightly, but some, including oak wilt and bagworms, can be detrimental to trees.
Here are some things you should watch out for:
"Really sparce foliage; maybe cracked, peeling bark popping off that's not a characteristic of that species of tree; possibly curled, ruffled leaves; a discoloration of the leaf itself; a lot of leaves on the ground right now in June and we didn't have, maybe not a heavy storm, but there's still indication of it looks like fall to you outside, and you have oaks specific," she said. "These are things you want to take note of when you place that call for us to help diagnose it."
If you can’t make it to the tree pest clinic Tuesday, you can send a photo of tree damage to a Missouri Department of Conservation forester for identification.
