• Fulmer Falls at George W. Childs Park

    Delaware Water Gap

    National Recreation Area NJ,PA

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  • Hornbecks Creek Trail Partial Closure

    The trail is closed between the first and second waterfall; a portion of the trail has sloughed off, causing a hazardous condition. The first waterfall is accessible from the 209 trailhead and the second waterfall is accessible from Emory Road.

  • Dingmans Falls Area and Road Closed

    Dingmans Falls Visitor Center, the boardwalk trail to the falls, and the access road will be closed through September as repairs to the road are made. We anticipate the area reopening in October.

Non-native Species

Aerial view of a field showing two different colors of vegetation

Autumn olive (dark bluish-green) invades a former crop field.

PHOTO: Bill Agne

Plants from far away find a new home. Many times they’re purchased at a local nursery and planted because they’re pretty; but they don’t just move in and settle among their neighbors, they take over the neighborhood and kick everyone else out! Invasive exotic plants can outcompete native species and form vast monocultures, changing entire ecosystems in the process. Some can change soil pH, produce toxins, outcompete native plants, and destroy critical habitat for many birds and animals. They threaten cultural landscape vistas, the health and safety of park visitors, vegetative riparian buffers along rivers like the Delaware and its tributaries, and State Natural Heritage Program Rare Plant Communities of Special Concern.

Upland areas are threatened by tree-of-heaven (Ailanthus altissima), autumn olive (Elaeagnus umbellata) (above), multiflora rose (Rosa multiflora), oriental bittersweet (Celastrus orbiculatus), Norway maple (Acer platanoides) and honeysuckle species (Lonicera spp.)

Wetland and riparian areas are threatened by purple loosestrife (Lythrum salicaria), common reed (Phragmites australis), and knotweed (Polygonum spp), while the forest understory is invaded by Japanese barberry (Berberis thunbergii), garlic mustard (Alliaria petiolata), and Japanese stiltgrass (Mycrostegium vimineum.)

Invasive exotics are not only plants, some of them are insects as well. Hemlock woolly adelgid is an aphid that attacks and kills hemlock trees-- trees that can normally live up to 400 years. Hemlock trees are a key component of our forested ecosystem, important for fish, birds, mammals and insects alike.

Human populations within a 6-hour drive of the Water Gap are expected to double within the next 20 years from 60 million to 120 million. With all of the construction, disturbance to natural systems, and land use requirements it will entail to house these people, native plant populations and ecosystems will be further stressed and even now-common native species may be in danger of decline. It will be more important than ever for protected areas such as national parks to serve as reservoirs for native species.


Did You Know?

A ranger in the uniform of the French and Indian War.

... that in the 1750s, the northwest border of New Jersey (now Delaware Water Gap National Recreation Area) was a frontier of the English colonies. In the French & Indian (Seven Years) War, a string of forts protected these settlements. The sites of seven of these outposts are in the park. More...