ST. LOUIS – A giant force of nature is vulnerable to a minuscule wasp, capable of destroying it. This is the conflict between the oak tree and the oak gall.
An oak gall wasp lays its eggs on the oak tree leaves and then infestation spreads. The spread could kill an oak tree but it can be prevented.
Glendale resident Debbie Goodman says neighbors weren’t sure what to make of them at first because squirrels eat the galls.
“Some of us that have the oak trees thought the squirrels were having a party or something,” said Debbie Goodman.
Goodman will be calling an arborist soon because healthy, vigorous trees are important.
Once the gall egg is laid on a leaf, it takes three years to mature. Galls can kill the trees but it’s a slow death that could take years.
“You’re not only seeing what damage you have this year, it takes three years for this to form,” said Nathan Cartwright, Davey’s Tree Expert Co. “So, what they did this past spring, you’re not going to see the damage until a couple years from now.”
So how can galls be treated? Cartwright says arborists at Davey’s use an injection.
“It’s almost like an IV into the tree and it protects the tree for two years, so as long as we get on a cycle and a program, it seems to make a difference,” he said.
If your tree is infested with galls, Cartwright says it’s better to be proactive than reactive with the galls.