Roanoke Times
                 Copyright (c) 1995, Landmark Communications, Inc.

DATE: MONDAY, June 20, 1994                   TAG: 9406200081
SECTION: VIRGINIA                    PAGE: C3   EDITION: METRO 
SOURCE: By CATHRYN McCUE STAFF WRITER
DATELINE: NEW CASTLE                                LENGTH: Long

TINY BUGS A BIG THREAT TO VA. FORESTS

He had traveled from Asheville, N.C., to assist local authorities in tracking the beast that has invaded this corner of Craig County in a devastating march through the southern Appalachian mountains.

Armed with a hand ax and a degree in entomology, Barry snagged his prey.

"This is the Southern pine beetle," Barry said, holding out his hand to expose the voracious herbivore. "There it is, a little tiny black thing."

On the tip of his finger lay, indeed, a little tiny black thing, like a mouse dropping. On its own, one beetle can't eat much.

In the thousands and millions, though, pine beetles can attack and kill a tree within a matter of weeks, turning a healthy stand of loblolly or white pine into worthless deadwood.

Infestations have hit Bedford and Botetourt counties and other areas of Southwest Virginia. The bad spots are easy to see - splotches of reddish-brown dead trees blemishing the mountain tableau.

The pine beetle isn't the only bug that finds our woods appetizing. The gypsy moth is swooping in from New England, and an obscure critter called the woolly adelgid is hitting Virginia hemlocks.

These pests don't provide the drama of a forest fire or the controversy of clear-cut logging, but they are nonetheless quietly taking their toll. Experts say it won't be long, in ecological time, before a good portion of the Southwest Virginia forests are dead.

"I would say it's very alarming, especially since we're entering into an environmental awareness on the part of the public," said Robert Anderson, a forest pathologist with the U.S. Forest Service office in Asheville who watches over forests in seven Southern states.

Last year alone, the Southern pine beetle killed 8.5 million trees in Virginia, the state Department of Forestry estimates.

Gypsy moth caterpillars have defoliated about 3 million acres in Virginia since 1984.

And the hemlock woolly adelgid, harder to track than the other two pests, has been found in at least 44 counties.

These bugs come at a time when Appalachian forests are vulnerable because of past use and natural events, Anderson said. In the 1930s, whole hillsides turned brown as the chestnut blight virtually wiped out an entire species.

The chestnuts were replaced by oaks, which aren't well suited to this region's soil and climate. And the oaks, already under stress, are aging and declining.

"Here comes the gypsy moth . . . and then you just get incredible mortality all over the place," Anderson said. Red maple, poplar, Eastern red cedar and other species are replacing oaks, changing the forests once again.

This time around, human hands have reached into the ecological mix. Turn-of-the-century "high-grading" - taking only the best trees - resulted in a genetically weakened forest. Clearing and burning the land for farming and heavy commercial logging caused extensive erosion and left poor quality soil.

The result is a mostly even-aged forest about 80 to 90 years old, Anderson said. The ecosystem is mature and declining naturally.

Now, the silent threat of pollution is creeping in. Ozone - beneficial in the atmosphere but harmful near the Earth's surface - and acid rain are showing up, adding stress to the ecosystem in still poorly understood ways. It's generally believed that pollution doesn't directly kill trees, but seems to weaken a plant's immunity to pests, ice, wind and other natural forces.

"We can't be looking at the gypsy moth or oak decline or chestnut blight - we've got to look at the whole system," Anderson said.

Looking into the future - beyond the brown patch of dead pine on a Bedford County hillside, the pocket of graying hemlock along the Blue Ridge Parkway and the swarms of gypsy moth caterpillars in the Shenandoah National Park - experts say the forests won't disappear.

They'll look different, display different fall colors and host different species of wildlife, but they'll still be forests.

In the meantime, the mountains are turning brown. The old oak in the back yard is threatened, stands of timber are being lost and the cost is mounting.

Here's a closer look at three of the major pests invading the Appalachian woods. Southern pine beetle This native bug breaks out every decade or so. The larvae eat through layers of bark, leaving tiny tunnels that kill the tree. The beetles also carry a fungus that chokes the flow of water and nutrients, and leaves a blue stain that reduces the wood's market value.

Beetles can produce five generations in one growing season. One female can lay 200 eggs. An active infestation can move 50 feet a day.

Since 1960, it's estimated that the pest has killed more than 36.6 million cords of wood - a stack four feet high, four feet wide, circling the Earth 2\ times.

Weather conditions have favored the beetle lately. Pine stands are thick, mature and vulnerable. The recent outbreak began in the Shenandoah Valley in early 1991. Bedford, Botetourt, Craig and Franklin counties have reported infestations of varying degrees.

Last year, there were 18,531 infestations in Virginia, ranging from half an acre to hundreds of acres. Fewer than a quarter of those spots were salvaged for sale, the rest dying on the stump.

This is the worst outbreak on record, but the end may be in sight. Barry, the beetle expert, checked his traps in Craig County this spring and found that 95 percent or more of the population had been killed by the cold winter. Plus, clerid beetles, the natural enemy of pine beetles, are on the rise.

"It is great news," Barry said, adding a note of caution. Pine beetles have a way of flaring up, so foresters will continue to monitor them through the summer.

Tim Tigner, chief entomologist with the Virginia Department of Forestry, estimates the outbreak has cost about $1.5 billion. That includes lost income from trees that died, trees cut prematurely in an attempt to prevent the spread of the pest, acres lost to production and lost income from the wood products processing.

Lynn Dickerson knows all about lost income. He owns a 70-acre certified tree farm in Botetourt County.

"Over the years, I've probably lost several thousand dollars to the beetle," said Dickerson, who lives in Richmond. "I just hate to lose those trees after planting them and caring for them for 40 years."

Dickerson faces the dilemma of many private landowners and big timber industries. Beetle infestations force landowners to cut trees before they've reached full economic value. Much of the pine goes for pulp, which brings less money than saw timber.

Right now, lumber is flooding the mills, dropping the price about 40 percent because of ice-storm and beetle damage. By harvesting now, Dickerson would get less money but it would help control the spread of the beetle by taking away its food.

If he waits until fall, the price may go up, but the beetle may do more damage.

"It will be a gamble. If you figure in the time and money I put in it, I would have been better off investing in the stock market." Gypsy moth

The frigid winter may have had the opposite effect on the gypsy moth. After several years of relative quiet in Virginia's battle against the moth, there may be a resurgence, said William Ravlin, an entomology professor at Virginia Tech who has followed the moth's progress for years.

"My guess is this past winter they did just fine," he said.

The moth is eating its way south and west through Virginia, the front line of attack lying roughly from Bath County to Pittsylvania County. Egg masses and larvae have been found in the Roanoke and New River valleys.

A French astronomer brought the moth over in 1869 in hopes of producing silk. Some escaped and began feasting on New England forests. Efforts to stop the moth began in 1905, with little success.

Caterpillars feed from May to June and often defoliate an entire tree. They prefer oak, but also feed on other hardwood trees. Depending on other conditions, most trees can withstand several defoliations before dying, so infestations aren't always deadly.

Northern Virginia and the Shenandoah Valley have been hardest hit, despite repeated sprayings of pesticides and a state quarantine. State agriculture inspectors try to check timber, nursery products and outdoor household items such as doghouses and picnic tables for signs of the gypsy moth, so named for its penchant for hitching rides and moving to new territories. The moth first showed up in Virginia in 1969 in Shenandoah National Park.

"It will do well here," Ravlin said. "We'll be able to look at Brush Mountain, and it'll be defoliated by, oh, say, the year 2005. It'll look like winter in the middle of summer."

It would be hard to assess the total cost of moth damage. There's lost timber value, lost revenue from recreation areas that have to be closed and the cost of pesticides. More than $6 million in federal, state and local funds has been spent since 1990 on pesticide spraying, said Gary McAninch, who heads the moth suppression program in Virginia.

Some tree growers in Rockbridge, August, Bath and Highland counties are thinning their hardwood stands in hopes of stalling the invasion.

Dickerson hasn't seen any moths on his trees in Botetourt yet. Spraying is too expensive, so watching is about all he can do.

"There's just things you can't do anything about," he said. Hemlock woolly adelgid Tinier than the pine beetle, deadlier than the gypsy moth, a bug called the hemlock woolly adelgid is on its way to infesting the entire range of eastern hemlocks in the next 20 years.

"It has the potential to kill all the hemlock trees in Virginia, and we have nothing at this point to stop it," said Anderson of the Forest Service.

The adelgid, a native of Asia, was introduced in the eastern United States in the 1950s near Richmond, apparently a stowaway on exotic tree species brought over by a private collector.

It lives in the bark, sucking the fluids and secreting a toxic saliva. Infested trees turn gray and die over seven or more years. Infestations have been found in Franklin, Bedford and Botetourt counties and the Roanoke and New River valleys.

Hemlocks aren't commercially valuable like pines and hardwoods, and make up less than 10 percent of the forest. Still, they play a crucial role.

Found primarily along streams, they shade the water in summer, maintaining the cold temperatures for native brook trout. Many bird, mammal and plant species depend on hemlock stands for food and shelter.

Humans also value hemlocks for their beauty, both in the wild and in their neighborhoods.

Not as much is known about the adelgid as the other two pests, probably because the damage is less noticeable and takes longer to appear, said David Gray, in Tech's entomology department. Hemlocks grow in patches scattered throughout the forest, so it's more difficult to track the adelgid populations and gauge damage.

This year, researchers found that many of the bugs seemed to have died over the winter, although Gray was hesitant to credit the cold.

He is among a small but growing number of researchers trying to learn more about the adelgid, including how to stop it. Pesticides are effective in urban areas, for individual trees, but not in the forests. The adelgid has no natural enemies in the East.

While homeowners, tree growers and timber companies want to stop the march of the bugs, public lands managers face a different question.

Increasingly, people are seeking out the solitude and beauty of forests and parks, to hike, fish and camp. But the public also is becoming more ecologically literate, Anderson said. They don't want dead trees, but they won't stand for large-scale logging or massive pesticide sprayings, either.

Resource managers tread a narrow middle path.

The pine stand in Craig County that Barry investigated was scheduled for an emergency harvest that would have bypassed some Jefferson National Forest logging regulations. Because of past public pressure, the agency first had to justify the cut. As it turned out, the logging was called off because most of the beetles had died from the cold.

The Jefferson generally allows the pine beetle to run its course on steep, out-of-sight slopes that aren't valuable for timber or recreation. When infestations threaten designated timber or campsites and other recreation areas, the forest may thin the pine stands to suppress the beetle.

But this beetle outbreak will subside. And although the gypsy moth might kill the 150-year-old shade tree in the front yard, oaks and other hardwoods will rebound as they have in New England after a century of living with the moth.

"In the grand scheme, bugs play a valuable role in the energy cycle," said Ravlin, the Tech entomologist. They break down leaves and wood that return nutrients to the soil, preparing the way for a new forest for future generations.