PlantLegitNew Hampshire: invasive & noxious plant laws
Under RSA 430:55 and rule Agr 3800, no one may collect, transport, import, export, move, buy, sell, distribute, propagate or transplant any living part of a plant on the New Hampshire prohibited invasive species list, including all cultivars and varieties. Variances are possible for scientific use. NH DES separately prohibits exotic aquatic weeds under RSA 487:16-a and Env-Wq 1303.02 (rule readopted January 25, 2025): they may not be offered for sale, sold, distributed, imported, bought, propagated, transported or introduced, and the ban also covers accepted synonyms (Env-Wq 1303.03). A proposed revision (initial proposal, July 2026) would split the list into Class A and B; it is not yet adopted, so the current adopted list is shown.
Official sources
- N.H. Admin. R. Agr 3800 Invasive Species (NH General Court)
- Agr 3802.01 (LII)
- NH Dept. of Agriculture — invasive plants
- Env-Wq 1300 Exotic aquatic weeds (NH General Court)
- RSA 487:16-a
- Federal Noxious Weed List, 7 CFR § 360.200 (USDA APHIS) — applies in every state
Prohibited invasive plant (N.H. Admin. R. Agr 3802.01) — no collecting, moving, importing, exporting, buying, selling, distributing, propagating or transplanting; includes all cultivars and varieties (35)
| Scientific name | Common name / notes |
|---|---|
| Acer platanoides | Norway maple |
| Ailanthus altissima | tree of heaven |
| Alliaria petiolata | garlic mustard |
| Alnus glutinosa | European black alder |
| Berberis thunbergii | Japanese barberry |
| Berberis vulgaris | European barberry |
| Celastrus orbiculatus | Oriental bittersweet |
| Centaurea stoebe subsp. micranthos | spotted knapweed |
| Cynanchum louiseae (syn. Vincetoxicum nigrum) | black swallow-wort |
| Cynanchum rossicum (syn. Vincetoxicum rossicum) | pale swallow-wort |
| Elaeagnus umbellata | autumn olive |
| Euonymus alatus | burning bush |
| Frangula alnus | glossy buckthorn |
| Glyceria maxima | reed sweet grass |
| Heracleum mantegazzianum | giant hogweed |
| Hesperis matronalis | dame's rocket |
| Impatiens glandulifera | ornamental jewelweed |
| Iris pseudacorus | water-flag |
| Lepidium latifolium | perennial pepperweed |
| Ligustrum obtusifolium | blunt-leaved privet |
| Ligustrum vulgare | common privet |
| Lonicera japonica | Japanese honeysuckle |
| Lonicera maackii | Amur honeysuckle |
| Lonicera morrowii | Morrow's honeysuckle |
| Lonicera tatarica | Tartarian honeysuckle |
| Lonicera ×bella | Bella honeysuckle |
| Lysimachia nummularia | moneywort, creeping Jenny |
| Microstegium vimineum | Japanese stilt grass |
| Persicaria perfoliata | mile-a-minute weed |
| Pueraria montana var. lobata | kudzu |
| Reynoutria japonica (syn. Fallopia japonica) | Japanese knotweed |
| Reynoutria sachalinensis (syn. Fallopia sachalinensis) | giant knotweed |
| Reynoutria ×bohemica | Bohemian knotweed |
| Rhamnus cathartica | common buckthorn |
| Rosa multiflora | multiflora rose |
Prohibited exotic aquatic weed (RSA 487:16-a; Env-Wq 1303.02, eff. Jan 25, 2025) — no offering for sale, selling, distributing, importing, buying, propagating, transporting or introducing (34)
| Scientific name | Common name / notes |
|---|---|
| Aldrovanda vesiculosa | waterwheel plant |
| Butomus umbellatus | flowering rush |
| Cabomba spp. | fanworts (includes C. caroliniana, a U.S. native) |
| Crassula helmsii | swamp stonecrop |
| Egeria densa | Brazilian elodea |
| Eichhornia crassipes | water hyacinth |
| Epilobium hirsutum | great willow herb |
| Glyceria maxima | reed sweet grass, manna grass |
| Hottonia palustris | water violet |
| Hydrilla verticillata | hydrilla |
| Hydrocharis morsus-ranae | frogbit |
| Hygrophila polysperma | East Indian hygrophila |
| Ipomoea aquatica | water spinach |
| Iris pseudacorus | yellow flag iris (rule spells "pseudocarus") |
| Lagarosiphon major | African oxygen weed |
| Limnophila sessiliflora | ambulia |
| Lythrum salicaria | purple loosestrife, and cultivars |
| Lythrum virgatum | wand loosestrife, and cultivars |
| Lythrum alatum | winged loosestrife (a U.S. native), and cultivars |
| Marsilea quadrifolia | water fern |
| Myosotis scorpioides | water forget-me-not |
| Myriophyllum spp. | all milfoils, including native ones |
| Najas minor | European naiad |
| Nymphoides peltata | yellow floating heart |
| Phragmites australis (syn. P. communis) | common reed (the rule does not separate the native subspecies) |
| Pistia stratiotes | water lettuce |
| Potamogeton crispus | curly leaf pondweed |
| Sagittaria japonica | double-flowering or Japanese arrowhead |
| Sagittaria sagittifolia | giant sagittaria |
| Salvinia molesta | giant salvinia |
| Trapa spp. | water chestnuts |
| Typha gracilis | slender cattail |
| Typha laxmannii | dwarf cattail (rule spells "laxmanii") |
| Typha minima | miniature cattail |
Check plants against New Hampshire law →
Informational only, not legal advice. Lists change; always check the official source linked above before you buy, sell, plant or move a plant. Lists checked 2026-10-14.