What you can do
Your landscaping choices can play an imporant role in contributing to your area's ecological health! Maintain and plant native vegetation wherever possible--this will not only support local biodiversity, it will also reduce your landscaping maintenance needs compared to a garden full of ornamentals not suited to this climate.
Native plants provide essential habitat for hundreds of species, and provide the foundation of a healthy ecological community. For example, there are over 600 species of insects in this area that can only survive on oak trees, and dozens if not hundreds of other species that in turn depend on those insects. Over 95% of bird species that either live here year round or migrate through depend on caterpillars for a large portion of their diet, and many caterpillars depend on very specific plant species, like oaks, for survival.
Native plants require less water, less fertilizer, less herbicide, and are more disease-resistant and hardy than most non-native vegetation. All of this means they'll stay healthy and you'll spend less money and put less chemicals into the environment in the process.
In addition, a large healthy native tree in your yard will cut down on air conditioning expenses if situated properly, and can add thousands of dollars to your property value.
Avoid planting common landscaping plants that are known to be aggressive invaders of our native woods. English Ivy, Vinca or Periwinkle, Pachysandra, Porcelainberry, Bamboo, Bush Honeysuckle, Wisteria, and Bradford Pear are some very commonly planted species that, when they escape and begin spreading in the woods, cause great environmental damage. Non-native invasives have few native predators to keep them in check. They crowd out native plants by growing fast, and reproducing early and in large quantities. Insects lose their host plants and disappear, the forest structure changes and becomes inhospitable for native wildlife, birds find little food and can no longer raise their young in the area, and in the worst case scenario, the result is essentially an ecological desert. So please, plant natives, or at least not invasives.
Create wildlife habitat. In addition to a thriving garden of native plants, filled with butterflies and birds, you can help other species of wildlife survive with a few simple additions to your yard. A water source will always attract wildlife, especially if it is running, flowing or dripping in some way (which will also reduce mosquitos). Brush piles over small stacks of rocks will provide shelter for small birds and mammals, though these should be kept at a distance from the house and living areas.
Reduce your Ecological Footprint
There are many ways to use fewer resources and reduce your impact on the earth. Turning off the lights, using less water, making use of re-useable containers and bags, and carpooling or biking to work are all obvious solutions, but there are other less obvious but powerful ways to help the environment with your daily choices:
Supporting your local farmer's market by buying locally-grown, seasonal produce saves vast quantities of fossil fuels that would otherwise be required for transportation. It also supports the rural economy and helps keep farmers in business, which means they're less likely to have to sell their farms to developers.
Planting native vegetation in your landscaping reduces the need for supplemental watering, fertilizer, herbicides, etc. Also the less lawn you maintain, the happier the environment around you will be--lawns are highly artificial environments, virtual dead zones when it comes to biodiversity, and standard lawn care (fertilizer, etc.) is a significant contributor to water pollution in our local streams and in the Chesapeake Bay.
Reducing your meat and seafood consumption has wide-ranging environmental benefits as well as health benefits. Raising animals for meat production requires vast inputs of land, water, grain (that could otherwise go to feed people), fossil fuels, etc. The key is moderation and choosing the source of your food carefully. Many vendors at farmers' markets offer meat products that are raised in ecologically sustainable and humane ways. Freshwater fish are also a more ecologically responsible choice than seafood--currently the oceans are being overfished across the globe, creating food shortages for higher level predators and upsetting the ecological balance of the oceans as a whole. Large scale fish farming creates massive water pollution and spreads disease to wild fish, so is not a very sustainable alternative.
Local Educational Opportunities
Curious to learn more about the natural world? Check out these organizations that offer excellent environmental education for adults!
Audubon Naturalist Society: Natural History Field Studies Certificate through the USDA Graduate School
Virginia Master Naturalists
Audubon Society of Northern Virginia