Step 4: Safeguard Pollinator Habitat
The legal definition of an invasive species, and the official position of the U.S. government, is “An alien species – not native to the ecosystem – whose introduction does or is likely to cause economic or environmental harm or harm to human health.” (“Alien” refers to species not native to the ecosystem).
Some invasive plants have been introduced accidentally. Others have escaped from our gardens. Once they establish in natural areas their ability to propagate in several ways and to thrive in many conditions allows them to spread rapidly. Because they have few or no natural enemies in their new home they can usually out-compete native plants. This upsets the delicate balance of local ecosystems and affects the insects and pollinators dependent on the natural habitat.
Some common garden plants that are on the invasive list are: Japanese Barberry (Berberis thunbergii); Burning Bush (Euonymus alatus); Autumn Olive (Elaeagnus umbellata). Another imported plant that is showing up on invasive lists is Buddleia davidii, better known as Butterfly Bush. It has been escaping to roadsides and natural areas in the Mid-Atlantic region and has the potential to displace important butterfly host plants.
What can you do? Avoid buying and planting invasive plants in your landscape. Consider removing any invasives already present. If you have a woodlot or meadow on your property remove any invasives and protect existing populations of native plants. Where invasives are removed, replant with native plants as soon as possible.

Japanese barberry invades a Pennsylvania forest

Oriental bittersweet swallows white pine trees in a York County park
Butterfly bush invades habitat along Rt 83
For more information and list of invasive plants in your area, click on the publications below:
- Weeds Gone Wild, Plant Conservation Alliance's Alien Plant Working Group
- Invasive.org, Center for Invasive Species and Ecosystem Health
- Invasive Plants, National Arboretum
- Invasive Plants in Pennsylvania, Pennsylvania Department of Conservation and Natural Resources
In order to certify, the following is required of your garden:
- Remove and/or avoid use of invasive plants
- Protect existing natural woodland or meadow
Reduce Pesticide Use
Pesticides do not distinguish between pests and beneficial insects and can be very deadly to pollinators. Using fewer and less toxic pesticides will also protect beneficial insects such as green lacewings, ladybird beetles and assassin bugs that are your allies in pest control.
Before reaching for a pesticide make sure you have identified the pest and have determined that it is a threat to the health of the plant. If you have trouble identifying the problem, your Cooperative Extension office can help. If a pesticide can’t be avoided, look for less toxic options such as insecticidal soap or horticultural oil. Be sure to read and follow the directions on the label and apply at the appropriate time to control the pest. Never use a pesticide when the plants are in bloom or when pollinators are active.
- Pollinators And Their Threats, Penn State University Pennsylvania Pollinator Series
- Pollinators, U.S. Fish & Wildlife Service
- Reducing Risks to Pollinators from Pesticides, North American Pollinator Protection Campaign
In order to certify, the following is required of your garden:
- Reduce or eliminate pesticide use
* Application for Certification *


