Spring: A Great Time to Scout for Invasive Plants

Bush honeysuckles leafing out in the spring

Drive down any country road or take a walk in your favorite woodlot and you'll probably find non-native plant species beginning to show themselves this spring. They have invaded our forests, stream corridors, meadows, and yes, even home landscapes. Have you ever walked your property and wondered why there seems to be plants that are taking over? There is a good chance some are exotic invasives.

Spring is a great time of year to scout for invasive plants. These invasive exotic plants tend to leaf out much earlier than our native plants. This allows you to effectively scout your property, identify what species you have, make note of locations, and plan how you will control it. For some it may be as easy as pulling it once you have it correctly identified. For others more complicated interventions may be required. 

Pulled bush honeysuckle

Your property may already be invaded by “exotic invasive” plants or you might have even accidentally planted some in your landscape that will soon escape and invade a nearby forest or stream corridor. As good stewards we need to become aware of the impact these non-native invasive species have on our local environment and learn to identify and properly control these species before they completely take over an area.

What is an “Exotic Invasive Plant”?

It is really just another name for a weed that was introduced from other countries and has escaped cultivation causing serious harm to habitats for native plants and wildlife. Before you start tearing out all your landscape plants, you must know that NOT all non-native plants are classified as invasive and there are some native plants that have a tendency to become invasive (for example hayscented and New York fern).  For a plant to be considered “invasive,” it typically grows aggressively (on various sites and growing conditions), spreads quickly (by seed, roots, or cuttings), lacks natural predators, pathogens and parasites, and displaces native plants.

Garlic Mustard flowers in the spring and is easily pulled.

So What Can Be Done to Prevent and Control “Exotic Invasives”?

•    Become Educated and learn what invasive species look like. Contact your local Penn State Cooperative Extension office in your county and request information (fact sheets) about specific invasive species or drop off plant samples for identification.

•    Don’t plant species that are considered invasive. Get a copy of plant listss that should not be planted.

•    Discover native alternatives in your landscape. Promote responsible gardening by learning about the native plants around you.  Buy nursery propagated native plant material.  Never dig or buy plants that have been dug in the wild. 

•    Remove or control invasive exotics plants from your landscape and replace them with native plants or non-invasive exotics. To properly control many invasive plants, some herbicide use may be required. Many can simply be pulled but for others pulling or cutting only encourage them to spread more.  The impact of leaving an exotic invasive to take over a site outweighs the use of herbicides to remove it.

Some Great Resources:

Garlic mustard: A Minnesota woodland owner's story

Penn State Forest Vegetation Management

Penn State Wildland Weed Management

DCNR Invasive Plants

DCNR Invasive Plants List

Plant Invaders of Mid-Atlantic Natural Areas

Article revised from "Has your property been “invaded”?" by Vincent Cotrone, September 2012.