The D&L Blog

Delaware & Lehigh - Restoring Native Plant Communities in the Corridor

CLICK PHOTO TO ENLARGE. This series of photos from our work at the Weissport Trailhead shows the removal of invase Tree of Heaven, seeding of native grasses and wildflowers, and restoration of native flora.

What is an “invasive plant”?

Invasive Plants are known as “non-native” species that come from Europe, Asia, and even parts of North America that damage the native ecosystems which stop the growth and spread of native vegetation. Invasive plants can be trees, shrubs, vines, grasses, or flowers which do not have natural enemies. This is one of the main factors in their uninhibited growth and colonization. The most aggressive spread rapidly and choke out native vegetation and alter the landscape.  The most notable seen across the Corridor include Japanese Knotweed (Polygonum cuspidatum or Fallopia japonica) and Tree of Heaven (Alianthus altissima). Click here for more information.

For information on specific invasive plants, refer to the following fact sheets:

Characteristics & Impacts of Invasive Plants

Japanese Knotweed fact sheet

Tree of Heaven fact sheet

How can we control them?

Invasive plants can spread by seed and by vegetation including rhizomes, runners, shoots, tubers, and bulbs. Control methods are determined by the landowner based on species, size of infestation, and research guidelines. Research shows it is important to understand thecharacteristics and means of reproduction of the invasive plant species to guide control methods.  Invasive plants should be removed and replaced with native species.  For more information, please see either this National Park Service information or PA DEP information.

How can we restore native plant communities?

A native plant include ferns and mosses, grasses, sedges, and rushes, perennial and annual wildflowers, woody trees and shrubs, and vines which covered “Penn’s Woods” when the first settlers arrived. There are over 2,100 native plant species known in Pennsylvania.

It is important to landscape with native plants to rejuvenate native plant communities which grow commonly across Pennsylvania.  Part of the ecological restoration process is to remove invasive plant species, control erosion and soil compaction, and plant with native species. Select appropriate native plants for the right environment and site conditions to enhance the ecosystem and landscape.  Click here for more information.