Controlling Invasive Plants and Animals in our Community

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1 Controlling Invasive Plants and Animals in our Community PROVIDED BY THE WILDLIFE COMMITTEE What makes a plant or animal invasive? When a plant or animal from another region of the world (usually Europe or Asia) is brought to our neighborhood, it can sometimes grow out of control, like a cancer. Usually such plants or animals are introduced through the landscape or pet industry. They can be the pretty flowers we plant in our yards or the unusual snail we keep in our aquariums. But the seeds from the pretty flower can spread to other areas by wind or birds. Or we might get tired of cleaning the aquarium we keep the unusual snail in and decide to set him free in one of our ponds or streams. Since our neighborhood lacks the normal diseases or predators found in their native lands to keep them in check, these organisms begin to take over the habitats that our own native plants or animals would normally occupy. Fairfax County defines invasive species a non-native species that cause ecological or economical harm. They share certain characteristics, such as being able to mature quickly, generate many offspring and can tolerate a wide range of habitats. For instance, Japanese stilt grass will produce seed in as little as 1% sunlight! Most non-native species introduced intentionally to Virginia, such as wheat, soy, horses and chickens, are beneficial. Many accidental introductions are harmless. However, some introductions become pests that have serious ecological and economic impacts. Nationally, invasive species result in an estimated annual cost of $120 billion, and as much as $1 billion annually in Virginia alone. Why is this a problem for our community? Our forests are being choked out by invasive vines and shrubs making some areas inaccessible or unsafe. We also have a costly infestation of water chestnut in our ponds. This is a non-native or alien, invasive plant as well. It has been spread through sale for aquariums and water gardens and has been distributed to our ponds by geese and people dumping out their aquariums or water gardens. As you can see, the problem of invasive species spread is not just an aesthetic issue but also and economic issue. Invasive species pose one of the primary threats to Virginia s natural heritage. They directly threaten native species and can alter landscapes and ecosystems. Ecological harm caused by invasive species can include near extirpation of native species, as in the cases of chestnut blight and hemlock wooly adelgid, and alteration of natural ecological communities, as has occurred with the common reed or may happen due to snakehead fish. Currently, 49 percent of 1,180 imperiled or federally listed species are directly threatened by competition with or predation by invasive species. The

2 Virginia Depart of Game and Inland Fisheries identifies invasive species as a crucial statewide conservation issue. Scientists estimate that invasive species are present in over 100 million acres of the U.S., or an area roughly the size of California, with 14 million new acres, or an area about half the size of Virginia, infested every year! Recent studies have estimated the cost of invasive species at more than $100 billion a year. Over the last 30 years, invasive species have slowly taken a firm foothold in our area. There are well over 300 invasive plant species that have been reported in Fairfax County. What can we do? 1. Don t plant invasive species. Instead of planting non-native or invasive trees, shrubs or plants in your yard, choose native plants or horticultural varieties that are not invasive. To uphold our motto of "Living in Harmony with Nature", we should not contribute in any way to the spread of other alien invaders in our community. 2. Learn more about invasive species. The National Park Service's Alien Plant working group has a web site devoted to informing the public about invasive plants that pose a threat to the natural biodiversity of the entire US The Virginia Native Plant Society and the Virginia Department of Conservation and Recreation maintain a list of invasive plants that pose a threat to Virginia's biodiversity 3. If you have invasive species growing in your yard, remove them See top ten invaders below). 4. Don t release unwanted pets into the wild, especially if they are not native to Virginia. Top Ten Invasive Plants in Burke Centre Water Chestnut (Trapa natans) This Asian aquatic plant has a rosette of sawtooth, triangular floating leaves at the water's surface, with a submerged stem that can reach 12 to 15 feet in length. Water chestnut can form dense floating mats, severely limiting light, and reducing oxygen levels, which may increase the potential for fish kills. It also limits boating, fishing, swimming and other recreational activities. Suggested control: Manual, mechanical and chemical techniques are used in its control.

3 Complete removal of plants is imperative, as floating, uplifted plants and plant parts can spread the plant to new locations. It is critical that any removal take place prior to the July seed set. Eradication is difficult because water chestnut seeds may lay dormant for up to 12 years. Burning Bush The wings on the stems make this plant really easy to spot that and the brilliant red fall color. Birds eat the fruit and spread the plant into the forest. Suggested control: Prevent fruits from forming by pruning off all flowers or remove the entire plant. Multiflora Rose Multiflora rose is a prickly plant once recommended as good fencing. Now it keeps people and wildlife out of the forest. material, including roots. Japanese Barberry Japanese barberry doesn t get eaten by deer, and therefore lots of people plant it. However, birds eat the berries and plant it in the forest where it doesn t belong. Suggested control: Prevent fruits from forming by pruning off all flowers or remove the entire plant.

4 Autumn Olive My mother always said if you ve got nothing nice to say, don t say anything at all. material, including roots. Pruning worsens the problem. Privet If you want to create a solid wall of vegetation that doesn t allow anything through, privet is your best bet. But that doesn t make any sense for natural areas! Suggested control: Prevent fruits from forming by pruning off all flowers or remove the entire plant. Bradford Pear Bradford pear escapes more frequently than Houdini ever did. Puffy white clouds of flowers stand out in the spring landscape, but the indistinct green leaves can make it hard to identify in summer. Suggested control: Tree must be cut down.

5 Pachysandra If you want a ground cover that is unpleasant and very aggressive, pachysandra is the one for you! The dense carpet formed by pachysandra keeps the diversity of native wildflowers from our forests. material, including roots. Bamboo There is nothing lucky about this bamboo. Dense bamboo infestations like this one prevent all native plants and most native wildlife from flourishing. material, including roots. This may be difficult, so repeated efforts will be necessary. English Ivy Let s leave the ivy at the Ivy League! English ivy can kill the trees that it grows on. Suggested control: Keep ivy under control or remove it entirely. Prevent ivy from spreading across horizontal and vertical surfaces. Do not compost clippings.

6 Oriental Bittersweet This strangling vine with bright red fruit will quickly turn into the biggest pest in the garden. Oriental bittersweet can kill anything it climbs on. material, including roots. Make sure clippings are disposed of with the trash so they won t be composted. Resources: Invasive Backyard Plants Invasive Forest Plants Native Backyard Plants Local Native plants PLANTS Database for State Noxious Weeds for Virginia