A mysterious condition is afflicting many sawtooth oaks in Wichita, and it may kill some of the city’s stalwart trees.
Vertical cracks are showing up at the base of sawtooths, extension agent Bob Neier said. Some of the cracks may heal over, and some may widen to eventually kill the trees, he said.
“We know it’s widespread and environmental, and we don’t know what caused it,” Neier said. “Probably 80 percent will heal over and maybe 20 percent won’t.”
Some of the oaks show signs that they’ve had the cracking before, and that it healed over. “We’re just hoping” that happens this time, too, Neier said.
Nothing can be done to help the condition, he said. Do not peel any bark off the tree, but if bark has naturally come off more than halfway around the trunk because of the cracking, the tree should be removed because it will die, Neier said.
“That bark will not come back. ... They’re not going to recover at that point,” he said.
Samples from affected trees have been tested for disease but showed no evidence of a pathogen, Neier said. That means that some environmental factor, such as a temperature extreme, is responsible.
Sawtooth oaks that have split have been found in all kinds of situations in the Wichita area, Neier said: in parks and in yards, in lush landscapes and those that aren’t irrigated, and in trees that are mulched and those that have grass growing right up to them. Many of the affected trees are in the 10- to 25-year-old range, he said.
The only thing that can be done for the trees is to be sure they’re watered during times of severe drought, he said.