A sign at the base of a trail leading into an electric-green oak forest in Annadel State Park reads: "Illegal Trail. No Trespassing. Area Under Surveillance."
Yet horse hoofprints, tire tracks and boot prints show how commonly people disregard park rules designed to keep some areas free from human impact.
Some call them "social" or "unofficial" trails. Others call them "outlaw" trails. Whatever the name, these trails are far more prevalent than official ones in Annadel.
The park is home to 44 miles of maintained trails. Park rangers estimate there are twice as many miles of paths off-limits to visitors.
Generations of ranchers, miners and wild animals wore paths before the area became Annadel State Park in 1971. But the recent crash of a cyclist who broke his neck on an illegal trail near Bennett Peak has highlighted tension between avid park users who stray from official trails and park stewards charged with preserving the area.
"What do you want Annadel to look like in 100 years?" State Park Supervising Ranger Neill Fogarty asked.
Annadel's paths traverse more than 5,500 acres nestled among Santa Rosa's eastern neighborhoods. The park, which is known for its quality biking, is rare because all but a mile of its official trails are open to hikers, bikers and equestrians.
A new series of educational placards soon will appear on popular paths to explain why the park is asking people to stay out of certain areas.
The sign was developed with the Sonoma County Trails Council and Bike Monkey, a cycling events group that puts on Levi Leipheimer's King Ridge GranFondo.
"It is a problem, yes," said Danita Rodriguez, acting superintendent for state parks' Diablo Vista District, which includes Annadel. "In Annadel, social trails are growing in numbers and heavily used."
Many users ignore park rules. An average of 410 people visit the park each day, but of those only about 20 people pay the entrance fee, according to an estimate based on 2010-2011 figures.
"The closer a park is to urbanization, of course it's going to get more use, and with more use there is more use legal or otherwise," Rodriguez said.
Park stewards say they are up against a culture of disregard, not just by cyclists but also equestrians and illegal campers.
"I think they're short-sighted," said Ken Wells, executive director of the Sonoma County Trails Council.
No cyclists, including avid mountain bikers, would speak publicly about why so many people ignore park rules.
In interviews, cyclists who did not want to be quoted, cited several reasons they head into uncharted areas, including that trails aren't always clearly marked as out of bounds, and official trails are in poor shape.
Some of Annadel's most popular stretches of trails have become pock-marked, rocky and dangerous.
Jim Keene, co-owner of the Bike Peddler and NorCal Bike Sport shops in Santa Rosa, said he has heard customers compare rutted official trails with relatively pristine secret ones.
"I don't ride on illegal rides. It's not something that I've ever been comfortable with. However, I know scores of people who do," Keene said. "They make a good case for themselves in that the (illegal) trails are better maintained. They're safer. They don't erode nearly as much."
Sonoma County Regional Parks took over park maintenance at Annadel in July after raising nearly $300,000 to keep the park open. The state had been threatening to close Annadel since 2009. The yearlong agreement will either expire or be renewed by the end of June.
The Sonoma County Trails Council has become the primary force behind trail maintenance and building projects, particularly after the state sharply cut staff. They bring volunteers to fix trails at least once a month, often more.
Wells said he has a list of potential projects and has prioritized problems with equal importance to hikers, cyclists and equestrians, such as deep ruts.
This summer Wells plans to start repairing the popular Marsh Trail.
"They're as good as they've been in the last 10 years," Wells said.
Annadel used to have maintenance staff and several rangers, but now Fogarty is the sole state staffer in the park. The county oversees maintenance, and county rangers respond to calls when Fogarty isn't working.
Bert Whitaker, Sonoma County Regional Parks operations director, said his department has spent about $10,000 since July repairing and replacing state-installed red posts warning people to stay off certain trails.
The county recently installed new, sturdier signs with the stronger message: "Area Under Surveillance."
He declined to say what kind of surveillance.
"We're not interested in writing a bunch of citations, but we really want people to respect the park," Whitaker said.
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