NEWS FROM THE DELAWARE DEPARTMENT OF NATURAL RESOURCES AND ENVIRONMENTAL CONTROL

August 22, 2008
Vol. 38, No. 384

For more information contact Lyle Jones, Division of Water Resources, 302-739-9939, Robert Line, Division of Parks and Recreation, 302-739-9220, or Melanie Rapp, Public Affairs, 302-739-9902. Photos available by contacting DNREC Public Affairs, 302-739-9902.

Banks of Dover’s Silver Lake
Cleared of Invasive Plants
Two-year Revitalization Underway

DOVER, Del. – Dover’s Silver Lake received a new lease on life when more than three acres of invasive plants were removed from its banks this week. A team of DNREC watershed scientists, Parks and Recreation environmental stewardship staff and Americorps volunteers spent two days removing English ivy, porcelainberry, multiflora rose and other plants in an effort to rid the area of non-native, invasive plants that have taken over and degraded the natural ecosystem.

“Eradication of invasive plants is very labor intensive,” said Lyle Jones, program manager with DNREC Division of Water Resources Watershed Assessment. “Invasive plants are very difficult to remove, so we used hand pruners to cut vines and applied an environmentally-friendly herbicide on the cut stems just above the roots of others, such as porcelainberry. Once the porcelainberry has died, we’ll be back to remove dead plants.”

Invasive plants are non-native species introduced to an area on purpose or by accident. Once established, invasive plants reproduce rapidly, spread over large areas of landscape and have few natural controls to keep them in check. They compete for natural resources, displace native plants and disrupt the environment’s delicate ecological balance. Some invasive plants spread so rapidly they change forest, meadow, or wetland into a landscape that is dominated by one species. Recreation can be affected when some invasive species become so thick that it’s impossible to enjoy outdoor activities and the beauty of natural areas.

The removal of the invasive plants at Silver Lake is part of a two-year revitalization project underway by DNREC and the city of Dover. 

“The project has tremendous benefits to the area,” continued Jones. “We are planting a tiered riparian buffer of native plants, shrubs and trees along the banks of Silver Lake and the St. Jones River. This buffer acts as a natural filter and can reduce up to 96 percent of the sediment, 95 percent of the nitrogen and 79 percent of the phosphorus and other pollutants from entering the water. It’s the most environmentally-sound, cost effective way to improve water quality, increase plant and wildlife habitat and provide a safer, more attractive area for public recreation and enjoyment.”

Last May, DNREC and the city of Dover grounds crew planted three species of native flowering plants – swamp milkweed, swamp rosemallow (a member of the hibiscus family) and black-eyed susan or orange coneflower – about 700 plants – in two test plots along the St. Jones riverbank. The plants were grown from seed by Polytech High School students. Earlier this year, nearly 50 native trees were planted, including maples, riverbirch, sweet bay magnolia and willow oaks. This fall a team will be back to plant more than 600 native shrubs and trees.

The revitalization program was originally conceived by the St. Jones Tributary Action team, a group of dedicated volunteers who live, work and recreate within the watershed. The project’s primary focus is to improve the water quality of the St. Jones River and Silver Lake, and the team developed pollution control recommendations that include adding buffers of native trees, shrubs and plants to filter pollutants from entering the waterways.

DNREC’s Watershed Assessment Section, Division of Water Resources, works with Delaware’s eight Tributary Action Teams, oversees the health of the state’s water resources and takes actions to protect and improve water quality for aquatic life and human use. For more information, visit  http://www.dnrec.delaware.gov/wr/Services/Pages/WatershedAssessment.aspx.

For information on invasive species, go to the Delaware Invasive Species Council website, www.delawareinvasives.net.