Roanoke Times
Copyright (c) 1995, Landmark Communications, Inc.
DATE: THURSDAY, May 10, 1990 TAG: 9005100583
SECTION: VIRGINIA PAGE: B6 EDITION: EVENING
SOURCE: Associated Press
DATELINE: BLACKSBURG LENGTH: Medium
Procerum Root Disease also may be a threat to pines grown in nursery plantations for resale and timber stands, said Sam Alexander, whose research has been limited to Christmas trees.
Experts at the Virginia Department of Forestry and Westvaco Corp., which owns large tracts of pine trees in Virginia used for making paper products, were unavailable for comment Wednesday.
"Procerum has been around for a long time, but until now it was only a serious problem in isolated areas," Alexander said. "It has just exploded."
Virginia is the nation's seventh largest producer of Christmas trees with about 1.8 million trees harvested each year. More than 1,400 growers are involved in the $20 million industry, according to Bill Francisco, president of the state Christmas Tree Growers Association.
The disease, caused by a fungus, has been found in numerous areas of eastern and Wastern Virginia, including the Blue Ridge Parkway, Hampton, Portsmouth and Suffolk, Alexander said. The disease also has broken out in West Virginia and Maryland, he said.
Researchers believe the fungus is carried from tree to tree by Pales weevils. The fungus then spreads to the tree's root collar and eventually kills the tree by choking off its supply of water and nutrients.
One of the first symptoms of the disease is that the new buds on infected trees don't break open or are much later opening than healthy trees. In some cases, resin may be seen on the outside of the bark near ground level.
Within weeks or months, depending on the size of the tree, the crown will turn from a lush green to a light green, then yellow and finally to reddish-brown. The needles will droop and wilt.
Once a tree is infected there is no way to treat it, Alexander said, and the only way to control the disease is to control the weevils.
by CNB