Hunt for hemlocks this Saturday at McConnells Mill

There was a time, before European colonization, when William Penn’s woods were literally that — 46,055 square miles of mostly forest land. From the deep river valleys to the high mountain tree lines, much of the land was shaded by a prolific, long-living species of flatneedled conifer tree that had adapted to live almost everywhere.

So adaptive is the Eastern hemlock that even after a century of logging it stands in urban backyards, shades native trout streams and remains Pennsylvania’s state tree.

On Saturday in Lawrence County, a family oriented hike will take participants on a 1½-mile hunt for hemlocks near the spectacular Slippery Rock Gorge at McConnells Mill State Park.

“Hemlock is our predominant evergreen tree,” said Natalie Simon, education specialist at McConnells Mill and Moraine state parks. “It covers the trail in places. Its low branches and soft wide needles shade the gorge so much it’s like it’s another climate in there. Hikers should bring a jacket.”

The hike begins with a brief staff-led clinic about Eastern hemlock trees. Participants hit the trail ready to spot, measure and count the hemlocks along the Alpha Pass Trail, part of the federally managed North Country National Scenic Trail that passes through seven northern states.

Throughout the American East, including Pennsylvania, hemlocks are in trouble. A small invasive insect, the wooly adelgid, has killed or threatened tens of thousands of hemlocks. Ms. Simon said resource managers from the state Department of Conservation and Natural Resources and Forestry Bureau are working with hemlocks in Ohiopyle, Cook Forest and other state parks, attempting to protect the giant trees from the tiny bugs.

“We have not found them here,” Ms. Simon said, “but we know [the adelgids] are not far away in Butler County.

The hike, said Ms. Simon, is all about building appreciation for the state tree.

“It’s a very long-lived tree — they can live about 800 years,” she said. “The ones that are older in our area grew on the steep, rocky gorge and were very, very difficult to log. That’s why they’re still there.”

If you’re going: The hike is free and meets at 10 a.m. Saturday in Point Parking Lot at McConnells Mill State Park (1761 McConnells Mill Road, Portersville, PA 16051). All ages welcome, but the hike is moderately difficult with some rocky ups and downs. Wear sturdy shoes or boots, dress for the weather, and bring a snack and water. It ends at about noon. Afterward, stick around for a spectacular Fall Foliage Hike. Free, 45:30 p.m. Meets beside Kildoo Pavilion, McConnells Mill State Park.