Clark Nature Preserve

About This Preserve

PRESERVE NOTICE: As we work to install the universally accessible Lloyd Clark Trail, the red-blazed trail through the Clark Nature Preserve meadow, as well as the two white connector trails to the Conestoga Trail, will be closed for construction. The parking lot and preserve will remain open during preparation and construction. Visitors can still access the Ralph H. Goodno Trail from the Clark Nature Preserve parking lot. Please be cautious of moving equipment during this time. Thank you!

Formerly three separate nature preserves known as House Rock, Reed Run, and Pequea South, Clark Nature Preserve was created and named in 2021 in honor and recognition of an extraordinary gift by the Clark Associates Charitable Foundation, in celebration of the Clark Associates’ 50th Anniversary. This important philanthropic contribution will help support land acquisition efforts and stewardship of the nature preserves in the Lancaster River Hills, an area along the Susquehanna River between Safe Harbor and Holtwood Dam.

Planning Your Hike

Ralph H. Goodno Trail Loop | 2.4 Miles – Strenuous

From the parking area at the end of House Rock Road, follow the posts demarcating the Ralph H. Goodno Trail, named in memory of the late Ralph Goodno, former Lancaster Conservancy President who during his 12 year tenure preserve over 2,500 additional acres of land. Turn south to stay along the edge of the meadow and enter the woods. Follow a single path dirt trail, cross House Rock Run, and connect with the Conestoga Trail at the House Rock Scenic Overlook. You can continue your hike south along the Conestoga Trail (passing the yellow and white trails to your left) before turning left to follow the blue blazes as you travel up along Reed Run. Complete the loop hike back up through the meadows to House Rock Road, and turn left to finish with a short road walk back to the parking area.

Out-and-Back Hike to House Rock Scenic Overlook | 0.6 Miles – Moderate

From the parking area at the end of House Rock Road, follow the posts demarcating the Ralph H. Goodno Trail. Turn south to stay along the edge of the meadow and enter the woods. Follow a single path dirt trail, cross House Rock Run, and connect with the Conestoga Trail at the House Rock Scenic Overlook. To reach the overlook, there is a moderate rock scramble. Return the same way you came to get back to the parking area.

Announcing the Lloyd Clark Trail – Coming Soon!

The Conservancy, in further recognition of a transformational gift from the Clark Associates Charitable Foundation, will also name a soon-to-be built universally accessible trail in memory of the Clark Associates’ founder, Lloyd Clark. This trail will loop through the meadow located by the main parking area at House Rock Road. The plans for this new trail also include accessible wildlife blinds and will provide even more members of our community, including those who use wheelchairs or other mobility devices, the ability to explore this unique meadow ecosystem, enjoy a winter view of the river, and participate in hunting, a passion of Lloyd Clark.

Ecology & Geology

Clark Nature Preserve is part of the ancestral lands of the Shenks Ferry and Susquehannock peoples as well as those who came before them. Deep eastern deciduous forests and pawpaw groves cover the steep sides of the river valley between schist bedrock outcrops. Open meadows in various stages of succession and patches of savannah have been restored on the plateau. As you hike, discover the diversity of ecology and landscape that make this preserve a special place.


House Rock Scenic Overlook, which offers a beautiful vista of the river, is a large outcrop of schist bedrock, which defines the Lancaster River Hills. It was formed from the sediments of an ancient sea that were heated and pressurized into twisted ropey bands of rock that shimmer with mica. Nearby you can find another geologic feature – Wind Cave, the largest tectonic cave in the east.


Clark Nature Preserve offers deep forests, dry rocky ridgetops, small clear cold streams, and open savannahs and meadows. The diversity of habitats lead to a diversity of organisms and the preserve is home to a wide array of plants and animals. Common meadow plants include milkweed, goldenrod, purple coneflower, butterfly weed, wild bergamot and warm season grasses. Monarchs, tiger swallowtails, admiral butterflies, goldenrod gall fly and grasshoppers are all insects supported by the native meadow vegetation and gold finches, bluebirds, swallows, kestrels, red tailed and red shouldered hawks like the open habitat. The meadows grade to late successional meadow and savannah as locust and oak trees start to grow and ultimately a mature deciduous forest lines the streams and Susquehanna River in a wide swath of oak, maple, tulip poplar and hickory trees. Paw paw and spicebush make up the shrub layer and the forest floor is home to an incredible display of spring
ephemeral wildflowers like Dutchmen’s breeches, Virginia bluebells, may apples, and trillium.

Restoration & Research Efforts

Meadow Habitat

Formerly agricultural crop land, Clark Nature Preserve has been managed by a series of partners to revert this preserve to its natural habitat. As part of the Cooperative Agreement program, PA Game Commission and the National Wild Turkey Federation helped the Conservancy establish native grass meadows in the northwestern portion of the preserve. Large areas of the eastern part of the preserve are being reforested through the Conservancy’s efforts with the Natural Resources Conservation Service’s (NRCS) Conservation Reserve Enhancement Program (CREP). A diverse array of native tree species has been planted into former agricultural lands to help establish greater protection of the preserve’s headwaters.

American Chestnut Research

Through the early 1900s, the American chestnut comprised one fourth of all trees in Appalachian forests. They were large, fast growing trees that were considered the “backbone” of the eastern forest ecosystem. But then the blight struck. The rapid decline of the American Chestnut was caused by a fungus introduced to the US in the 1800s from Asia. The loss of the American chestnut had a huge impact on the Appalachian forest ecosystem because its seeds, flowers, and leaves were the primary food source for wildlife. As we continue to lose other native local species like Elm and Ash to invasives, the opportunity to restore the American chestnut to the hole it left in the forest ecosystem many years ago becomes even more significant.

As part of the American Chestnut Foundation’s numerous research plots, four American chestnut groves were planted on this preserve. Two of the groves that are crossed with Chinese chestnut fill in gaps between woodlands north of the main parking area. All of these groves provide the opportunity to study chestnut blight resistance while helping to reforest this preserve and restore habitat.


Three beautiful river hills streams, House Rock Run, the tiny Brubaker Run, and the larger Reed Run, flow through the woods of the preserve, with many small waterfalls as the streams descend to the Susquehanna River and on into the Chesapeake Bay.

Hunting Information

House Rock is open to Mixed-Use Hunting. Respect property boundaries and safety zones. All Pennsylvania Game Commission Rules and Regulations apply. See ‘Where to Hunt’ for more details.

Report Hunting Violations: PA Game Commission Centralized Dispatch Center at 1-833-PGC-HUNT (1-833-742-4868) or 1-833-PGC-WILD (1-833-742-9453)

Acquisition History

2003 – REED RUN

The 148 acres of land that originally made up Reed Run Nature Preserve was acquired at a public auction in 2003 with funding from the PA Department of Conservation and Natural Resources and the Community Parks Initiative of Lancaster County.


This property, totalling 96 acres was acquired in 2006 with funding from the PA Department of Conservation and Natural Resources and the Natural Lands Preservation Fund of Lancaster County.


143 acres of land were donated by Brookfield Renewable in 2020, as part of the final phase of land transfers which began in 2010 led by an ongoing partnership effort to protect the Susquehanna Riverlands Conservation Landscape. This decades-long public-private partnership focuses on protecting land, responsibly stewarding natural and cultural resources, and connecting the community and visitors to this landscape. Partners include the Pennsylvania Department of Conservation and Natural Resources, The Conservation Fund, Lancaster and York Counties, PPL, Talen Energy, Brookfield Renewable, National Park Service, and Susquehanna National Heritage Area. These partners have worked together with local municipalities, and state and federal resource-based agencies to protect natural lands, waterways, riparian buffers, and wildlife habitat for the public.


400 House Rock Road, Pequea PA


Parking. Kiosk. Semi-Permanent Port-a-John.


Header Photo by Dustin Underkoffler from House Rock Scenic Overlook at Clark Nature Preserve.

Prevent Tick Borne Illness!

  • Wear repellent
  • Check for ticks after your visit
  • Shower soon after being outdoors
  • Call your doctor if you get a fever or rash

For more information visit

Spotted Lanternfly Alert!

Lancaster County is a Spotted Lanternfly quarantine area. This highly invasive insect is a serious threat to the health of our forests.

What you can do to help:

  1. Report spotted lanternfly sightings to Penn State Extension or call 1-888-4BADFLY.
  2. Stop the Spread. Look before you leave! Check gear, vehicles, and trailers.
  3. Smash them, bash them, kill them dead.
  4. Scrap and smash egg masses.

Emergency Information

In case of emergency, call 911

Nearest Hospital – 14.9 miles away
Penn Medicine Lancaster General Hospital

555 N. Duke Street, Lancaster, PA 17602

Additional Resources

Rawlinsville Fire Company

PA State Police