In 2012, the Ballston Pond Invasive Plant Management Project was initiated by the Department of Environmental Services in coordination with the Department of Parks and Recreation. The goal of the project is to contribute to the ecological health of the pond by eliminating, to the extent possible, invasive plants that harm the local ecology and to lay the groundwork for maintaining the pond in an invasive-free state for future generations.
What Is an Invasive Plant?
The 1999 Federal Executive Order on Invasive Species defines an invasive species as a species that’s not native to a particular ecosystem and whose introduction does or is likely to cause economic or environmental harm or harm to human health (Code of Virginia §2.2- 220.2). Invasive plants dominate new areas because they’re without the natural controls that would keep down population in their native settings. Some of the negative impacts to natural areas include degradation of ecosystem health and displacement of native plant species, which provide important habitat and food source for wildlife.
Three invasive plant species have been targeted for management in Ballston Pond:
Alligatorweed – Alternanthera philoxeroides
Appearance: Emergent or rooted floating plant with opposite, elliptical leaves that are up to 4 inches long. Flowering occurs during the summer with white, clover-like heads.
Ecological Threat: Roots in wet soils or shallow water and grows out into waterways. The thick mats can displace native vegetation and wildlife habitat, clog waterways, restrict oxygen levels of water, increase sedimentation, interfere with irrigation and prevent drainage.
Water Primrose – Ludwigia peploides
Appearance: Perennial herbaceous plant of wetlands whose sprawling stems usually grow flat along mud or the surface of the water. Leaves are alternately arranged and range from 0.5-4 inches. Solitary flowers have five yellow petals, 0.4-0.6 inches (1-1.5 centimeters) long.
Ecological Threat: Forms dense, fast-growing, floating mats that can displace native aquatic plants, wetland grasses, lower dissolved oxygen and pH of the water, reduce water quality for wildlife, and increase sedimentation.
Purple Loosestrife – Lythrum salicaria
Appearance: Erect perennial herb with a square, woody stem usually covered by downy hair; 4-10 feet high, depending upon conditions. Leaves are arranged in pairs or whorls around the stem. It produces a showy display of magenta-colored flower spikes throughout much of the summer.
Ecological Threat: Under favorable conditions, purple loosestrife is able to rapidly establish and replace native vegetation with a dense, homogeneous stand that reduces local biodiversity, endangers rare species and provides little value to wildlife.
What Can You Do?
You can help this effort by identifying and removing invasive exotic plants on your own property. For more information, visit our Invasive Plant Program online, and then click on “Additional Resources.” There you can download two booklets, “Plant Invaders of Mid-Atlantic Natural Areas,” and “Mistaken Identity?: Invasive Plants and their Native Look-Alikes.” You can also contact the Invasive Plant Program at 703-228-1862 for more information.