What's Happening to the Dogwoods?
A new disease of dogwoods first appear in Seattle, Washington around 1976.
By 1978 the disease was found around New York City. Between 1978 and 1987,
the disease devastated dogwood populations in the northeast.
In 1988 Dr. Mark Windham, professor of plant pathology at the University
of Tennessee, discovered the disease in the Cherokee National Forest in
Polk County, Tennessee.
"The Forest Service sponsored a meeting in Dillard, Georgia
in February of 1988, because they had found it (the disease) in North Carolina
and Georgia. After that meeting, I knew what to look for. On the drive back
along highway 64, just into Polk County, I saw some trees on the side of
the road that looked like what we had been shown in Georgia and North Carolina.
I collected some samples and that's what it turned out to be."
What was Dr. Windham looking for? Spots, blotches and blights.
Spots
The spots are light brown in the middle and have
red or purple edges and a yellow halo.
Sometimes the center of the spot falls out
leaving a hole in the leaf.
Photo by Margery Daughtrey.
Blotches
Blotches are bigger than spots and
usually develop at the end of the leaf.
Photo by Margery Daughtrey.
Blight
Blight covers the entire leaf and can
then progress into the stem to cause new
limb infection and cankers.
Cankers are places where the bark and
wood have died.
Photo by Craig Hibben.
