Settlement is expected next month, but the preserve will not be immediately open to the public.
Located about six miles west of West Chester, the roughly rectangular property stretches nearly four miles as the crow flies. It starts at Route 162 across from the former Embreeville State Hospital complex and extends south, reaching almost to Route 842.
It encompasses rolling hills, hollows and valleys, meadows and uplands, fields of grains, forests, marshes, ponds, riparian woodlands framing streams too small to have a name, and a long, lovely stretch of the west branch of the Brandywine Creek.
"It's huge and diverse," said Morrison. "And remote - there are places on that property where there is no evidence of the 20th century."
At the northern edge, a chirping cedar waxwing, its black mask resplendent in the morning sun, flitted effortlessly through an enormous sycamore tree, the leaves creating a soft green canopy across the Brandywine.
Along the creek banks, an exuberant crowd of youngsters from Avon Grove Middle School were launching canoes into the chilly water, forming a haphazard flotilla as the current carried them downstream.
Earlier, Zeke Hubbard, owner of Northbrook Canoe Co., was barking out instructions to more than 100 students, all wearing orange life-jackets and fully prepared to get wet.
He warned about low-hanging branches. "Don't lean backward - you'll get stuck in a tree," he said. "Lean forward."
"Brown runs you aground - that's shallow water," he said. "Follow the green!"
Nearby, song sparrows were singing, red-winged blackbirds darted through the meadows, and overhead a red-tailed hawk rode the thermals, spiraling higher into a brilliant blue sky.
Just beyond the railroad tracks of the Penn Eastern Line that cut through the landscape, four tall cedar trees stand sentry at the corners of Potter's Field, an old graveyard that is the final resting place for anonymous residents of the 19th-century county poorhouse at Embreeville.
Cannery Road, named after a mushroom cannery that operated on the property years ago, bisects the new preserve at the halfway point, forming the boundary between the Lenfest land and the county land.
Winding along a small, unnamed stream through a wooded glen is Lost Trail Road, part of the preserve's southeastern boundary.
Much of Lenfest's land is classic Chester County farmland, with immaculate fields of corn, soybeans, wheat and hay.
As the trust begins an in-depth inventory of the preserve's natural resources and develops a long-range management plan, the farm fields are not likely to change for several years, said H. Scott Wendle, the trust's vice president for preserve stewardship.
Lenfest, 77, a former owner of Suburban Cable, is one of the region's best known philanthropists. He is chairman of the board of trustees of the Philadelphia Museum of Art, and through the Lenfest Foundation has become a major benefactor to arts and educational institutions throughout the region.
He bought his Chester County property in 1987, intending to build a house and live there. At one point, Lenfest said he considered developing about 125 acres near Route 842 and putting up condominiums. The outcry was predictable.
"There was so much opposition from the local people, especially Nancy Hannum," he said. "She's in love with that part of the Chester County and wanted to preserve it. I listened to her."
Hannum is legendary in the region for her love of foxhunting and her love of open space. The deal with the trust allows the hunt and other equestrian pursuits to continue using the property, but there are no plans for it to become an "equestrian destination," Morrison said.
Wendle said he planned to enhance the preserve's habitat by converting the fields of cool season grasses to native warm season grasses the Leni-Lenape would have seen when they trod the land before European settlement.
Cool-season grasses cover the ground with single stalks, Wendle said, but warm-season grasses grow in clumps, allowing room for birds to build their nests and find food for their young, and protecting them from predators.
This step alone will improve the ecology of the tract by attracting groundnesting birds such as bobolinks and eastern meadowlarks, native insects and butterflies.
The conversion will be a long process, possibly taking a generation or more, he said. In the meantime, the trust will also be developing public access points, parking areas and trails.
"The uses going on now will continue, but it will be a while before we are inviting folks on and having what we consider to be an active program," he said.
Larry Lewis, owner of Early Bird Nature Tours, has spent several years monitoring bird life on the Embreeville portion of the tract, especially around the marsh at the northern end. For attracting birds, warm-season grasses would be a terrific addition to the site, he said.
"Management is going to be critical," he said. "If it's done right, it could be wonderful."
Morrison said she expected the preserve to be a magnet for hikers and bird-watchers as well as for those seeking something increasingly rare in today's world - a refuge from the frenzy of today's world.
"It's a place for renewal," she said. "And it's becoming more important and meaningful to have these places - and for folks to be able to access them."
Contact staff writer Nancy Petersen at 610-701-7602 or email@example.com.