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RALEIGH, N.C. -- The droopy sprig of dead maple leaves looks like a victim of bugs. As a forester with the N.C. Forest Service, Jason Hewitt has seen this countless times before.
Since last month, when an organism that can devastate oak trees was discovered in North Carolina nurseries, leaves such as these have become suspects. They could be the first signs that the disease known as sudden oak death has escaped into the wild.
After a brief examination, Hewitt puts the crumbly gray leaves in a plastic bag that will be sent to a lab.
"I'd hate to be the person to say, 'Oh, that's not it,' and then it is," said Hewitt's searching partner, Laura Lazarus, bagging up honeysuckle and rhododendron leaves with brown spots. "We see spots every year, but we'll wait for the lab tests to tell us it's nothing new."
The N.C. Department of Agriculture found the fungus-like organism that causes sudden oak death on shrubs at nine plant nurseries across the state. All of the plants that tested positive were camellias that came from the Azusa, Calif., location of Monrovia Growers.
The state's other 60 nurseries that bought stock from the Azusa location had no infected plants when Agriculture Department inspectors arrived. But customers already might have bought diseased plants, or the disease's spores might have spread on the wind to surrounding forests, state officials say.
Now, the search is on.
With the help of $85,000 in federal money, the Department of Agriculture has tested all of the 69 high-risk nurseries at least twice and now is moving on to nurseries that bought plants from other locations in California.
Soon, the department will ask homeowners who think they might have bought infected plants to send in samples.
State agriculture officials say they will keep hunting for the disease for at least a year.
The Forest Service, which got $60,000 in federal funds to fight sudden oak death, has foresters combing the woods around the 69 nurseries for signs of the disease. After those tests are finished, they will begin surveying the woods from the air to check for dying oaks.
The disease doesn't do its worst until it spreads from a host -- which could be a camellia, a viburnum bush, a rhododendron, a honeysuckle vine or one of about 70 other plants that are susceptible -- to an oak. Infected oaks develop sores that bleed purple sap. Once enough sores develop, all the tree's leaves die within weeks.
The disease has killed thousands of oaks in California. Officials don't know whether it would be as destructive in North Carolina, since it has never been found on an oak here.
"We're treating it at the most conservative level," said Gene Cross, plant pest administrator for the N.C. Department of Agriculture, "because we don't know what it will do."
On Wednesday, Lazarus, Hewitt and fellow forester Jason Moan met at a North Raleigh plant nursery. It was their 23rd nursery in three weeks.
They survey surrounding forests and spend a few hours tramping through thick vegetation, climbing over downed limbs and watching for snakes as they search for bushes with brown leaves or oak trees with sappy sores.
They have plenty of scratches and chigger bites to show for their work. So far, they've found almost no suspicious oaks, and labs at N.C. State University and Mississippi State University haven't returned any positive tests. There are, however, still dozens more samples to be tested.
On this muggy morning, they collect eight more -- all maple, honeysuckle and rhododendron leaves.
They crawl under thorny vines, make their way down a steep muddy bank and brush past poison ivy vines to pluck leaves and examine the bases of oak trees. They prowl around a few suburban lawns to check the landscaping for signs of disease.
All the spots they find look like the innocuous fungi they see every year, but they're not taking any chances. They bag them all up for testing.
"There are so many things that cause spots," Moan says, reaching for a spotty maple leaf at the edge of a lawn. "It's like looking for a needle in a haystack."
Friday, June 18, 2004