Longtime Orme Ranch managers Alan and Diana Kessler must deal with the massive damage unauthorized, unrestricted OHV use causes.
"Sometimes I feel like I'm the only one who cares," Alan Kessler said. "The trails don't heal over, and what is not often recognized is the 'staging areas,' where large areas of grass are trampled out by campers, trailers, fire pits and increased and concentrated traffic."
Other OHV users see a bare area and continue to use it, he noted. Some recreational OHV users, and sometimes hunters, cut fences, leave gates open and even injure livestock, leading to economic and safety concerns.
"There are a lot of nice people out there. But nice or not, the sheer numbers cause resource damage," Kessler said. "Sometimes I feel like I'm the only one who cares."
He isn't by a long shot.
The ecological impacts of vehicles driving off-road have been recognized since the 1920s, and some of the damage remains nearly 100 years later.
"Meinecke (1928) recorded damage to the roots of redwood trees," Australian Ralf Buckley said in his 2004 book, Environmental Impacts of Ecotourism.
That was decades before the advent of modern OHVs and the controversy their use causes.
Although OHVs benefit professions from ranching to border patrol, even limited use destroys fragile landscapes. That was apparent visually, but scientifically not well documented until the past couple of decades.
With an explosion of recreational use, the environmental impact of OHVs is a worldwide concern, with studies from Alaska to Australia.
In the 1960s and 1970s, the rapid growth of vehicle recreation prompted scientific studies by federal and state land-managing agencies, according to a report by Michael Sampson, California associate state archeologist.
Buckley said researchers began to focus on particular ecosystems, including the U.S. Southwest.
What they found was 4-wheel drive vehicles and trailbikes applied five to 15 times the pressure to the soil as that of a hiking boot, and that can be 10 times greater when OHVs are braking, accelerating or skidding.
Immediate effects are to break up soil crusts and compress deeper layers. Ultimately, this increases erosion, destroys vegetation and introduces non-native plants.
Other researchers have found wildlife can suffer specific damage, such as hearing loss in kangaroo rats, desert iguanas and fringe-toed lizards. This interfered with the animals' ability to detect predators, especially rattlesnakes.
Spadefoot toads, mistaking OHV noise for thunder associated with the rainy season, emerged early from their burrows.
Even the results of humans traveling where they otherwise might not go - from litter to fire - are under the microscope.
"There are enormous differences in impacts between different OHV users. Driven carefully at the right speed, with the right tyres, in the right places, by a well-informed user, a 4WD vehicle is a perfectly reasonable and legitimate way to enjoy many landscapes. Driven carelessly or with deliberate impacts, in fragile areas, by an ignorant or heedless user, OHVs can rapidly cause major and ecologically significant damage to soils, plants and animals," Buckley concluded.
USGS staff member Robert Webb, an adjunct associate professor of geosciences at the University of Arizona, has made a career studying the environmental impact of OHVs. He published Environmental Effects of Off-Road Vehicles, Impacts and Management in Arid Regions (1983), documenting the results of OHV use in California's Mohave Desert.
"But until 2008, I did no research because I could find nothing scientifically interesting about it," Webb said.
Webb now has unpublished data on the subject.
"What is scientifically interesting is the amount of time required to recover," he said. "Soil compaction associated with extreme use, such as you would find in an OHV pit area or heavily used road takes 100 to 125 years to recover fully IF there's no additional disturbance."
He said vegetation recovery, regardless of species composition, takes 80 years to recover in the Mohave Desert, but can take up to 1,000 years in fragile areas.
"No one's done any real research in Arizona," Webb said.
He now measures compaction from foot traffic and OHVs in Organ Pipe Cactus National Monument near Ajo, Ariz.
"What I'm trying to do is develop an objective method for testing soil and the vulnerability of soil compaction. There are no value judgments. It's to help land managers better manage our national resources," Webb said.
"We look at it as anything from a border patrol agent driving around trying to catch drug smugglers to recreational use."
His conclusion: environmental damage occurs rapidly but heals slowly.
"The main thing is, the greatest changes occur within the first few passes," he said. "What could be done by an OHV in a few hours can take decades to recover."
Sheer numbers of OHVs translates to rapid destruction of the environment.
OHV numbers in the U.S. tripled during the decade from 1993-2003. The inter-mountain west, including Arizona, has the greatest participation rates, according to USGS research ecologist Michael Duniway.
Steve Carmickle, an Arizona Game & Fish volunteer and past president of the Arizona Off-Highway Vehicle Coalition, said statewide it's a $3.5 to $4 billion industry, with about 400,000 OHVs of all types.
"Dealers say it's the largest growth market in Arizona," Carmickle recently told ranchers during the annual Cattleman's Association Convention in Prescott.
Longtime Queen Creek rancher Craig Shelley is leading an effort to revamp OHV use.
"I'm just trying to get people aware and get the facts out," Shelley said. "There is a lot of (scientific) information out there and none of it is good for the OHV user."
Next week: social and economic impacts, viewpoints and possible solutions from OHV enthusiasts, ranchers and government land managers.For the full article check.... http://www.cvrnews.com/main.asp?SectionID=1&SubSectionID=446&ArticleID=55918