INC NEWS - disease on the way for our oaks

[RW Pickle]

This past week I had the opportunity to spend a couple of hours with our
newest urban forester, Alex. I learned something that led me to the
internet to find out more. It was relative to a disease spreading across
the country that kills several oak species. In particular, the red oak (of
which we have many here in our neighborhood as well as across the City).
It's not a matter of if it will get here, it is only a matter of time
before it does. And there appears to be no solution in sight to protect
our oaks. I guess this is like a similar plague that wiped out the elm and
chestnut trees in this country.

Below is a copy and paste from a USDA NRCS National Plant Data Center
paper I found online. This helps to explain why all of new plantings (in
the City) are of the white oak variety. The fungus has not mutated to
cause them any concern (yet).

"This disease most seriously infects species of the red
oak group (including black and live oaks). Overcup
oak, bur oak, white oak, and other members of the
white oak group are not as susceptible and can be
planted in oak wilt centers. Oak wilt has reached
epidemic proportions in Texas and in the mid-West
from Iowa and Minnesota through Michigan and
Wisconsin into Ohio, West Virginia, and
Pennsylvania."

"Northern red oak is susceptible to oak wilt, a fungal
disease that invades the water-conducting vessels and
plugs them. As water movement is slowed, the
leaves wilt and rapidly drop off the tree. The disease
begins with a crinkling and paling of the leaves,
followed by wilting and browning from the margins
inward. Necrosis may be strongest along the veins or
between them. The symptoms move down branches
toward the center of the tree and the tree may die
within 1–3 months, although some diseased trees
may survive up to a year. The disease may be spread
by insects (primarily beetles) or pruning tools, but
most of the tree loss in oak wilt centers results from
transmission through root spread between adjoining
trees. A trench (dug and then immediately filled)
between neighboring trees severs the roots and
prevents fungus spread. Dead and infected trees must
be destroyed – once a tree has become infected, there
is little chance to save it. The wood may be used for
firewood provided it is debarked or covered and
sealed during the spring and summer (Johnson and
Appel 2000; Roberts 2000; Wisconsin Dept. of
Natural Resources 2000; City of Austin 2000). "

It's hard to imagine the amount of debris we'll have here when the fungus
finally arrives. From our neighborhood, it would be massive. And without a
solution for disposal other than hauling it off to VA, it looks like it
will an expensive proposition to deal with as well. It's hard to imagine
our landscape without all of our large oaks. But I guess we'll see what
that picture looks like soon enough...

RWP
27 Beverly