Winter is usually a slow time for garden work, but it is actually a great season to find invasive plants. While most of our local native plants lose their leaves or go to sleep (dormant) for the winter, many invasive species stay green all year long. Because they are the only green things in the woods, they are much easier to spot!
Common Invasive Plants to Look For
You might already know some of the most common plants that stay green in the winter:
- English Ivy
- Japanese Honeysuckle
- Multiflora Rose
- Pachysandra
- Privet
- Vinca (Periwinkle)
- Wintercreeper
Early Detection: Catching the New Invaders
We also track a group called Early Detection & Rapid Response (EDRR). These are plants that are just starting to spread into our wild areas. If we find them now, we can stop them before they take over.
- Heavenly Bamboo (Nandina domestica)
- Holly Olive (Osmanthus heterophyllus)
- Italian Arum (Arum italicum)
- Leatherleaf Mahonia (Berberis bealei)
- Leatherleaf Viburnum (Virbunum rhytidophyllum)
- Lilyturf (Lirope muscari and spicata)
- Stinking Hellebore (Helleborus foetidus)
- Trifoliate Orange (Citrus trifoliata)
- Wintergreen Barberry (Berberris julianea)
- Yellow Archangel (Lamium galeobdolon)
Your Challenge: Try to learn just one plant from this list. Next time you go for a walk, keep an eye out for it. If you find it growing in a park or wild area, take a photo and upload it to the iNaturalist app. This helps park managers know exactly where to go to protect our local environment!
Extra Challenge: Species on Watch
These are species that have become invasive in other states or counties, but we only have seen a few plants in the wild. We are monitoring these plants to see if they do become invasive here. If you are up to the extra challenge, keeping an eye out for these plants would be super helpful. Plants marked with an * are ornamentals.
- Bushkiller (Causonis japonica)
- Creeping mazus (Mazus miquelii)*
- Cut-leaf Blackberry (Rubus lacinatus)
- House’s Holly Fern (Cyrtomium falcatum)*
- Japanese Holly Fern (Cyrtomium fortunei)*
- Oregon Grape (Berberis aquifolium) *
- Spotted Laurel (Aucuba japonica)*