Delaware Bay Estuary Project
Northeast Region

Invasive Species

Invasive species are organisms that are introduced into a non-native ecosystem.  Invasive species are harmful to our natural resources (fish, wildlife, plants and overall ecosystem health) because they disrupt natural communities and ecological processes.

porcelain berry
Invasive porcelain-berry

Porcelain-berry Control in Milford, Delaware

The City of Milford, Delaware, has the largest infestation of porcelain-berry (Ampelopsis brevipedunculata) known in the Delaware Estuary.  Porcelain-berry is a deciduous, woody, perennial vine, in the grape family. It was originally brought to the United States from Northeast Asia, around the 1870s, as a landscape plant.  Porcelain-berry is a vigorous invader of open and wooded habitats.As it spreads, it climbs over shrubs and other vegetation, shading out native plants and consuming habitat. Porcelain-berry spreads by seed and through vegetative means. The colorful fruits, each with two to four seeds, attract birds and other small animals that eat the berries and disperse the seeds in their droppings. The seeds of porcelain-berry germinate readily to start new infestations. Porcelain-berry is often found growing in riparian areas downstream from established patches, suggesting they may be also be dispersed by water. This exotic vine potentially threatens some of the most valuable habitat in the Estuary in the Milford Neck Region.  

Milford Neck is a 10,000 acre conservation area that includes state and private conservation land holdings. This area has been recognized for its importance to migratory birds because of its extensive forest and wetland habitat. In addition it provides habitat for rare plants, reptiles, and amphibians. Expansion of porcelain-berry into the Milford Neck area would result in habitat degradation and the loss of biodiversity. The Mispillion River flows through the city of Milford, and then through the Milford Neck conservation area, before emptying into the Delaware Bay. This gives porcelain-berry an easy route into Milford Neck, and throughout the Delaware Bay, from the City of Milford. This threat brought together a team of local, state, federal, NGOs, and private landowners to form the Porcelain-berry Task Force.

Removal Success

The hard work and dedication by the Porcelain-berry Task Force resulted in the removal of 180+ acres of porcelain-berry in Milford, Delaware.  Three types of control methods: (1) manual - hand pruning followed by stem treatment; (2) mechanical - mowing and brown brush monitoring; and (3) chemical - foliar treatment applications were used.  Approximately 80% of the sites that were treated are located in open forested wetlands, the remainder in upland edges and backyards.  A public meeting was held to educate the landowners of Milford about the crisis and steps they can take to control the problem on their land.

Project Partners

City of Milford Department of Parks and Recreation, Delaware Department of Agriculture, Delaware Department of Natural Resources and Environmental Control, U.S. Department of Agriculture, U.S. Fish & Wildlife Service, Delaware Riverkeeper Network, Partnership for the Delaware Estuary, Inc., Integrated Vegetation Management Partners, Inc., National Fish & Wildlife Foundation, Sussex County Agricultural Center, Friends of the Milford Library, Delaware Department of Transportation, Delaware Office of State Planning, University of Delaware Department of Plant and Soil Sciences, Delaware Forest Service, Sussex County Agricultural Center.

For more information visit the City of Milford Parks and Recreation (Delaware) website at  or call them at 302-422-1104
Last updated: July 18, 2012

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