Decades ago, an exotic menace with spores eliminated the region's most common tree, the American chestnut. Gypsy moths, a foreign species with wings, have hammered the watershed's oaks. More recently, the nonnative woolly adelgid, a tiny insect with a voracious appetite for hemlock sap, has killed huge numbers of these majestic evergreens and threatens their entire range.

Now comes an invasive species with hooves that threatens to rip up the mid-Atlantic's forests by their roots: wild hogs.

Their swath of destruction reaches beyond forests, wildlife and water quality to include farmland and even human health.

"Feral hogs impact every part of the ecosystem," said Michael Bodenchuk, director of U.S. Department of Agriculture Wildlife Services in Texas. "They are crop deprecators and they affect human health. They eat endangered species. It's the perfect storm of all kinds of conflicts."

In Texas, approximately 2 million wild hogs wreak havoc on the landscape, and that's a conservative estimate. Damage from coyotes has been the longstanding priority in Texas, but hogs now compete for attention-and funds. Texas is spending millions of dollars to offset just a portion of their destruction.

Texas and Pennsylvania share a problem with wild hogs, but on vastly different scales. But Bodenchuk has a message for Pennsylvania: Act now.

"I get sent to other states to be the bad example," he said. "I tell them, if you don't do something when you've got 3,000 of them, you could look like us in 10 years."

Many believe that Pennsylvania's hog problem is at the tipping point.

The USDA estimated in 2007 that up to 3,000 wild hogs are trampling the landscape in at least 11 counties, but their current status is unclear. Wild hogs are prolific breeders and notoriously hard to catch or kill.

Most have been imported to Pennsylvania from southern states to stock private shooting preserves. They get into the wild by escaping captivity and from deliberate release.

Taking decisive action now could spare Pennsylvania another costly and permanent burden on its farms, forests and waterways. Instead, the response has languished, hindered by policy questions and inadequate funding.

The nonprofit Pennsylvania Biological Survey, with unanimous support from approximately 150 scientists in the state asked in early 2008 for $250,000 in the state budget to begin a more aggressive program to eliminate the hogs. The money didn't come through.

"We have all these scientists in agreement that this is a major problem in the commonwealth, but they just can't get the money together," said Frank Felbaum, past president of the survey. "It's like Nero playing the fiddle while Rome is burning."

Wild hogs pose a serious threat to forests and wildlife. They root up the forest floor and eat almost anything they find-plants, grubs, acorns, bird and turtle eggs, frogs, salamanders and fawns. They consume seeds and seedlings critical for new growth.

"The problems are in localized areas right now, but if we don't manage for it, swine could be a landscape-level concern," said spokesman Seth Cassell for the Pennsylvania Bureau of Forestry. "If they get to a critical mass, they could have an impact on everything from tree seedlings, shrubs and herbaceous cover to wildflowers and fungi."

In Texas, Bodenchuk found that hogs impact tree-nesting birds, as well as those on the ground. Tree-nesting birds eat insects, but the swine consume so much vegetation that the insects are affected, too. That, in turn, reduces nest success.

"It's an ecological train wreck," Bodenchuk said, "with one thing slamming into another."

Wild swine also destroy stream banks. Erosion and mudslides clog forest streams, and feces pollute the water.

Many Texas watersheds are impacted by E. coli bacteria, and Bodenchuk said that wild hog feces are a big part of the problem. His agency reduced E. coli in one watershed by 49 percent by removing only 260 hogs. "It went from unsafe by EPA standards to way below the EPA limit, just by removing a relatively minor number of hogs," Bodenchuk said.

Wild hogs disrupt farm operations across the nation. They eat crops, young goats and lambs, and damage field equipment with uprooted terrain. They carry airborne diseases with the potential to devastate pork production. The 2006 outbreak of E. coli from California spinach has been linked to contamination from wild hogs.

Jack Mayer, a wild hog expert at the Savannah River National Laboratory in South Carolina, found that 21 of the 44 states with wild hogs have an "established population," meaning that removing the hogs entirely is no longer realistic. Virginia is among those states-it has a small but persistent population on state and federal lands near Virginia Beach. Pennsylvania is not.

Instead, Pennsylvania has an "emerging" population that might still be eliminated through hunting and trapping.

The Western Pennsylvania Conservancy has supported two requests for state funds to help contain or eliminate the hog problem, including the 2008 request by the Pennsylvania Biological Survey. Both efforts failed.

Charles Bier, a conservation biologist with the conservancy, said it could be a costly mistake.

"This is an invasive species that we could potentially do something about," Bier said. "It's still possible, but it's difficult for people to get on the same page."

Containing the hogs, let alone removing them entirely, would depend on a coordinated and aggressive strategy, as well as better funding and an effective relationship with Pennsylvania hunters.

Pennsylvania initially tackled the problem with a task force drawn from public agencies and stakeholder groups. The task force sought ways to fund an effective program, but without success.

Action also stalled because it was unclear which agency had the lead responsibility for wild hogs. The hogs live both in confined areas on shooting preserves and loose in the forest, blurring distinctions between domestic operations and wild game.

The role appeared to fall within the Pennsylvania Department of Agriculture, which already had some authority over shooting preserves to protect livestock from wild game that carries disease. Just as the department was about to act, a 2007 Pennsylvania Supreme Court decision relegated authority for hogs "outside the fence" to the Game Commission. The lower courts have yet to detail how authority falls over shooting preserves.

"It was a recipe for disaster," said Harris Glass, director of USDA Wildlife Services in Pennsylvania. "The Game Commission is doing the best they can, but it was pushed to an agency that was not given the financial resources to do the job."

The Game Commission wants to eliminate the state's wild hog population entirely. That's a bold position for an agency that serves the hunting public, some of whom want free-ranging wild hogs for game. Shooting preserves are legal. Importing wild hogs is also legal if the reserves follow procedures for health inspections before the hogs are transported.

Game Commission veterinarian Walt Cottrell finds no conflict in the policy.

"The Game Commission is dedicated to the conservation and management of native species," Cottrell said. "This is a non-native, invasive species that competes with native species and destroys habitat. With this in mind, we find it easy to declare war on feral swine."

Cottrell said the real challenge is to get the job done. "We find it difficult to marshal resources because of lack of direction from the courts and lack of capacity to turn off the faucet," Cottrell said. "Right now, anything we do is just a finger in the dike."

Combating wild hogs is difficult under any circumstances.

They have large litters of eight to 12 young, sometimes twice a year, and often succeed in raising the entire litter to adulthood. Their numbers can double or triple in four to 12 months if conditions are right.

Some researchers estimate that a wild hog population must be reduced by approximately 70 percent each year-for several years-before the population is eliminated. A population of 1,000 could take nine years to remove. But wild hogs are not easy to hunt because they adapt their diet and disperse to new territory. They even become nocturnal to evade hunters.

Trapping can be effective while numbers are low, but the work is labor-?intensive. As a result, the Game Commission asks hunters to help kill the hogs. They can be shot any time of year with the proper safety precautions and the landowner's permission. Hunting is prohibited in areas where the Game Commission has an active trapping operation.

Involving public hunters has mixed results.

"In a lot of states, this has proved to be not effective and we're already starting to see it," Glass said.

Public hunters can help kill hogs but usually won't eliminate them unless the numbers are extremely low. Instead, public hunting often extends the hogs' territory by driving survivors into new areas and raises enthusiasm for hog hunting. Hunters don't always report their kills because they fear government trappers will remove the local hog population.

"They see it as another huntable species, not a threat," Glass said. "Educating everybody involved is one of the hardest things to do."

The Pennsylvania Department of Agriculture hopes to reduce the number of escapees from shooting preserves with a new set of rules that took effect in June.

David Griswold, a veterinarian with the department's animal health and diagnostic services, said that hogs on hunting preserves must now have ID tags in their ears so that escapees can be traced back to the preserves. Imported hogs must have a paperwork trail to show their origin and health tests. Males must be castrated so they can't breed in the wild.

"If a hog is loose and it has a tag, we can cite the preserve owner for not having adequate confinement. We can also go on any of these preserves to see if the hogs have identification and demand to see the paperwork for where they came from and the testing that was done on them," Griswold said.

But department resources are strained. Twenty-four field workers are responsible for inspecting 24 regulatory programs. Hog issues, which fall under the 1,000 hoofed-animal operations the agency inspects, are a small part of the whole.

"Enforcement will have to be complaint-driven," Griswold said.

At the Game Commission, Cottrell prefers sweeping action. "We need the courage and political will to make it illegal to own, possess or transport these animals in the state of Pennsylvania. Without it, we're not going to get anywhere."

Nebraska, Kansas, and Wisconsin have similar laws in place.

Texas, technically, has no problem with a hog elimination program. One doesn't exist. Wild hogs are unprotected in Texas, and anyone can shoot them, any time they want. "But do the math. Shooting does nothing to a population of 2 million," Bodenchuk said.

Instead, they focus on damage control.

"We go to the hot spots and do the best we can," Bodenchuk said.

The USDA and its state partners kill or trap hogs to protect peanut and corn crops through the growing season. And they protect sea turtle eggs on a barrier island because, yes, wild hogs swim.

"We have hogs that walk that beach and find every nest and eat every egg. So we try to remove every pig that can get to the island, at least for a short period of time," Bodenchuk said.

Short-term damage control is the best they can hope for, given limited financial resources in the face of 2 million swine. "Pennsylvania has a chance at eradication if they jump on it soon but, mathematically, we don't," Bodenchuk said.

Glass, though, fears that Pennsylvania's chance is fading. "Here in Pennsylvania, it's going to take all the regulatory authorities working together and at this time there really isn't a mechanism to make it happen."