Griffith Park South : Open space: A 6,600-acre portion of the Irvine Co.’s reserve will be opened. Company official says it will be an Orange County centerpiece.

A 4-year-old promise to open a vast swath of land that has been closed to the public--the 6,600-acre southern portion of the Irvine Co. Open Space Reserve--is about to be fulfilled, company officials announced.

Donald Bren, chairman of the Irvine Co., said the land, which will open next month, will rival the greatest urban parks in America.

“It will be the centerpiece of the county, like Central Park is the centerpiece of New York,” Bren said of the open space, which is being created in exchange for development rights on adjacent land. “It will be to Orange County what Griffith Park is to Los Angeles; a place bringing relaxation and relief from our busy lives.

“It’s an incredible asset that has been blocked by barbed wire for more than a century,” Bren said of the parcel, which stretches from Coast Highway near Laguna Beach inland through Emerald Canyon and from Laguna Canyon Road to Crystal Cove State Park. “We think it is socially and botanically important to the community.”

Actually, Irvine Co., the county’s largest developer, announced in 1990 that it intended to eventually make the property accessible to the public via docent-led tours. However, the opening of the reserve’s southern Emerald Canyon portion, which was scheduled for last October, had to be postponed because of the Laguna Beach fire, which destroyed about 80% of it.

In the seven months since then, the area has experienced a dramatic recovery, experts say. So on Saturday, it was announced Thursday, the public will be able to hike through the area for the first time, accompanied by docents.

“We want people to witness firsthand the recovery from the fire,” said Trish Smith, a Nature Conservancy biologist overseeing the project. “It really is quite remarkable.”

In 1992, the company signed an agreement with the Nature Conservancy--a nonprofit conservation organization--to preserve and protect the natural resources of the land while developing a program to provide public access to it.

The agreement covered three pieces of Irvine Co. land totaling 11,000 acres. The pieces are not contiguous, but all are along Laguna Canyon Road.

Last year, the program began with the opening of Limestone Canyon to docent-led tours. The program is expected to be completed this fall with the opening of 2,800 acres in Weir/Gypsum Canyon farther north.

For now, the southern 6,600 acres in Emerald Canyon are getting the attention, especially after the land’s impressive recovery from the devastating fire.

An advance tour by van of the reserve Thursday revealed the bustling of natural life resuming. Where six months ago the landscape looked black and barren, it now provides nourishment for fields of purple wild hyacinths, red Indian paintbrushes and yellow California sunflowers. And a land not too long ago seemingly devoid of life now supports red-tailed hawks, meadowlarks, bobcats and mule deer.

According to Smith, strenuous five-hour hiking tours led by Nature Conservancy volunteers will be available on the first and third Saturday mornings and afternoons of each month beginning Saturday. Also, 13-mile mountain cycling tours and 10-mile equestrian tours will be offered twice monthly.

To make reservations for tours, call (714) 832-7478.

“You can be here and think that you’re the only person in the world,” said Monica Floria, one of the firm’s senior vice presidents, gazing wistfully at the green and brown hills during the recent tour.

“It’s a great experience coming out here,” Smith said. “People are always amazed at the vastness of the open space. Every time I come here I experience something totally different. That’s what keeps me excited; there’s a surprise around every corner.”