RANCHO BERNARDO -- Local researchers clad in orange vests are preparing to fan out into the woods this week to launch a yearlong hunt for detailed information about what people do when they visit the Cleveland National Forest, U.S. Forest Service officials say.

"They're going to be throughout the forest," Anabele Cornejo, a forest service spokeswoman in Rancho Bernardo, said in a telephone interview Monday. "They may be on trails. They may be at campgrounds."

Visitors might also stumble upon researchers while driving through to take in the scenery. Cornejo said at points on forest roads signs will be posted that say "Traffic survey ahead," and those bright orange vests won't be far away.

Al Colby, Palomar Ranger District recreation officer, said the first interviews with recreation enthusiasts are scheduled for Saturday at the Wildomar Off Highway Vehicle staging area and the Tenaja Trailhead leading into the San Mateo Canyon Wilderness, in Southwest Riverside County.

It's all part of the first effort in six years to gauge the recreational interests of visitors to the sprawling but fragmented forest that spans 437,000 acres in three Southern California counties.

"San Diego, Riverside and Orange counties are still growing, and they're not going to stop growing," Cornejo said. "The needs are changing and we need to be ready to meet them."

The project is scheduled to wrap up in September 2009, after surveyors talk to people at 54 sites in all three of the forest's districts, Colby said. The Palomar district is in North San Diego County, the Trabuco Ranger District straddles the Riverside-Orange county line and the Descanso district is in southeastern San Diego County.

Cornejo said the Forest Service contracted with Cal State San Marcos to conduct the study. The research team will be composed of university students and employees, she said.

Cal State also has been asked to survey visitors of San Bernardino National Forest in central Riverside County and San Bernardino County and Los Padres National Forest north of Los Angeles, she said.

In the Cleveland National Forest, visitors will be asked what places they visited, how many people they traveled with, whether they stopped at any other sites and whether they were satisfied with the campgrounds and other facilities they used. Cornejo said visitors also will be asked to supply confidential personal information, such as age, income and ethnicity "to see who are the visitors."

Cornejo said the answers will help shape forest programs and improvements.

For example, she said, officials believe there is a trend toward larger groups, which may indicate a need to place two tables at each picnic site instead of one.

Increasing interest in enjoying the forest from the comfort of one's own car could indicate the need for other improvements.

"One of our growing user groups is folks driving for pleasure," Cornejo said. "We wouldn't necessarily come into contact with them at a campground or on a trail. This is one way of getting into contact with those folks who are just cruising."

The last survey found that more than 800,000 people visited annually, with viewing natural features, looking for wildlife, driving for pleasure, relaxing and hiking/walking being the top five activities.

Cornejo said the number of visitors is probably closer to 1 million today.

Contact staff writer Dave Downey at (760) 745-6611, Ext. 2623, or ddowney@nctimes.com.