ADDISON COUNTY — Although lumber companies are concerned with possible onset of the invasive emerald ash borer, they’re currently preoccupied with a case of the ash yellows — a sometimes fatal disease that slows the growth of ash trees.
The main cause is a mycoplasmalike organism (MLO) — an organism with no cell wall — that Addison County Forester Chris Olson said “defies categorization.” But he indicated there are other potential stimuli that may encourage such symptoms in ash trees like an overly wet, too dry or other extreme environmental conditions.
He explained that the primary MLO spreader in Addison County is the spittlebug, which can often be found on long blades of grass, where it leaves behind a path suggestive of saliva. The spittlebug transmits the MLO to the plant and the organism dams the tree’s circulatory system.
“It basically clogs the plumbing of the tree and causes what looks to be like drought-like symptoms,” said Olson. “If you’re looking at ash trees and you see them dying from the top down, it’s a pretty good bet that the trees are infected by MLOs.”
Even if there was a method for killing these MLOs, Olson thinks that people would still find problems with ash.
“Ash is a fickle tree and has limitations related to changes in soil moisture or temperature and different environmental variables,” he said.
Reporter Andrew Stein is at [email protected].