Several common landscape plants have made it onto NH and Massachusettes Invasive Non-Native Species List. They are deemed to be invasive due to their rapid growth and ease of propagation, which causes them to crowd out native plants. The best known example of this is Purple Loostrife.
The Burning Bush (Euonymus alatus), Japanese Barberry (Berberis thunbergii) and Norway Maple (Acer Platanoides) are not legal for sale and were prohibited starting January 1, 2007. This includes the popular Crimson King Maple which is actually a Norway Maple, not a Red Maple as many people think.
The following is the list of Currently Prohibited Plants in NH:
- Tree of Heaven (Ailanthus altissima)
- Garlic Mustard (Alliaria petiolata)
- European Barberry (Berberis vulgaris)
- Oriental Bittersweet (Celastrus orbiculatus)
- Black Swallow-wort (Cynachum nigrum )
- Pale Swallow-wort (Cynanchum rossicum)
- Autumn Olive (Elaegnus umbellata)
- Giant Hogweed (Heracleum mantegazzianum)
- Yellow-Flag Iris (Iris pseudacorus)
- Blunt Leaved Privet (Ligustrum obtusifolium)
- Showy Bush Honeysuckle (Lonicera x bella)
- Japanese Honeysuckle (Lonicera japonica)
- Morrow’s Honeysuckle (Lonicera morrowii)
- Tatarian Honeysuckle (Lonicera tatarica)
- Japanese Knotweed (Polygonum cuspidatum)
- Common Buckthorn (Rhamnus cathartica)
- Glossy Buckthorn (Rhamnus frangula)
- Multiflora Rose (Rosa multiflora)
- Fanwort (Cabomba caroliniana)
- Variable milfoil (Myriophyllum heterophyllum)
- Purple loosetrife (Lythrum salicaria)
- Common Reed (Phragmites australis)
