Preservationists and Developer Plan Joint Study of Open Space : Environment: The Irvine Co. will open 16,000 acres to hikers, bicyclists and other park users. The impact people would have on animals and plants will be examined first.

IRVINE —  The Nature Conservancy is joining with the Irvine Co. in a landmark study to determine how well people will mix with wildlife on 16,000 acres of land destined to become public parks.

The study is an outgrowth of the developer’s decision last spring to accelerate the opening of its property to hikers, bicyclists and other park users. The land is scheduled to be transferred from the Irvine Co. to public agencies over the next 20 years in exchange for the firm’s right to develop other tracts.

During a press conference Tuesday, company officials said they discovered a need to develop an overall strategy for how to manage the land and identify which parcels are most environmentally sensitive.

“As we went out and met with environmentalists, the issue really was not so much access as it was preservation and conservation,” said Gary Hunt, Irvine Co. senior vice president.

He added that public use may not be compatible with some of the endangered species found on some of the land and therefore should be limited “so we don’t, in fact, defeat the purpose for which we are setting this property aside.”

Once the $250,000 study is completed in June, the national conservation group will enter into a separate agreement with the company to manage the property until it is turned over to the governmental agencies.

The result, Irvine Co. Vice President Carol Hoffman said, will be well-managed property with an accompanying land-use plan that would otherwise have to be developed by the cities and county governments acquiring the parcels.

“Over the last 10 years,” Hunt said, “the company has really developed a better understanding of some of the uniqueness of some of this property. To the extent we can do everything possible to preserve that treasure, I think we want to do that.”

The degree to which the public will be allowed access, versus the preservation of wildlife habitat, will depend on the the master plan that is developed, said Stephen Johnson, the conservancy’s director of science and stewardship.

One area offered as an example of where public access may hurt the habitat is the Quail Hill area, where wild geese land. Other land could be open for guided tours, hiking, bicycling and other recreational uses, officials said.

Hoffman said three areas that could be open to the public as early as July are the 2,400-acre site known as Newport Coast, next to Crystal Cove State Park and featuring open space ridgelines and majestic ocean views; the 5,500-acre Limestone Canyon site, southeast of Irvine Lake, which includes a unique geological formation known as the Sinks, and Upper Peters Canyon, a 350-acre parcel within the cities of Tustin and Orange.

These properties are the top candidates for public access because they are close to major roads and highways and because many trails previously created for ranch management and firefighting already exist, Hoffman said.

Other properties to be studied include Bommer and Shady canyons, Quail Hill, Lomas Ridge and Muddy Canyon. The part of Laguna Canyon on the west side of Laguna Canyon Road--scheduled to be bought by the city of Laguna Beach in June--will also be included in the survey, she added.

The study “brings a very credible, well-known, respected environmental organization with a proven track record (to help preserve) Orange County’s natural open space resources,” Michael Phillips, executive director of two Laguna Beach environmental groups, said after the press conference.

The Nature Conservancy, known for its work in protecting habitats and natural resources, also credited the company with taking steps to protect land that might otherwise worsen over time.

Hunt said of the 64,000 acres of land now owned by the company, about half has been identified as open space or parkland. In addition to 16,000 acres set aside in the stewardship program, 10,600 acres have already been passed on to public ownership, and another 6,000 will be dedicated as open space when planning is completed on the Irvine Ranch’s northernmost properties.

THE IRVINE CO. PLANNED OPEN SPACE

Of the 16,000 acres of Irvine Co. land that will eventually be turned over to public agencies and kept for open space, the company has identified three acres where public access may be available beginning in July, 1991.

The Newport Coast: 2,400 acres of open space, including ridgelines with views of the Pacific Ocean and deep canyons dotted with huge sycamore tress. It is next to the existing 2,800-acre Crystal Cove State Park.

Limestone Canyon: 5,500 acres of some of the county’s pristine natural woodlands and home of the unique geological formation known as the Sinks. It is southeast of Irvine Lake and straddles the Lomas de Santiago Ridge.

Upper Peters Canyon: A 350-acre parcel surrounding a man-made reservoir. It is situated within the cities of Tustin and Orange.