USA: Border States Plant Regulations

Summary of Approaches

Federal, FED
Alaska AK
Idaho ID
Maine ME
Michigan MI
Minnesota MN
Montana MO
New Hampshire NH
New York NY
North Dakota ND
Ohio OH
Pennsylvania PE
Vermont VT
Washington WA
Wisconsin WI

map of USA with Canada border states highlighted
USA – States that share a border with Canada

U.S. Regulatory Approach

In 2016, U.S. Executive Order 1352 Safeguarding the Nation From the Impacts of Invasive Species identified invasive species as a national issue and established the National Invasive Species Council (NISC) to coordinate federal invasive species efforts and information sharing.

Federal authorities play a central role in regulating which plants may be imported into the country and which may be moved across state borders. Federal law does not regulate the sale of invasive plants. As a result, plants identified as invasive or listed as Federal Noxious Weeds may still be legally sold within a state if they are propagated locally, unless a state chooses to impose additional restrictions.

At the federal level, the U.S. Department of Agriculture (USDA) regulates plant importation and interstate movement under the Plant Protection Act (7 U.S.C. §§ 7701–7786, 2000) and the Federal Seed Act (7 U.S.C. §§ 1581–1610, 1939).

Under the Plant Protection Act (PPA), invasive plants may be designated as Federal Noxious Weeds (7 CFR Part 360), listed as Not Authorized Pending Pest Risk Analysis (NAPPRA) under the Plants for Planting regulations (7 CFR § 319.37-4), or regulated indirectly as hosts for other plant pests. These designations restrict importation into the United States and interstate movement, but they do not prohibit in-state propagation or sale.

Import requirements for plants for planting are set out in the Plants for Planting Manual (most recently updated in 2021), which details the conditions under which plants may enter the country.

The Federal Seed Act (FSA) governs agricultural and vegetable seed quality and labeling. It requires disclosure of weed seeds and sets zero tolerance for designated noxious weed seeds, while allowing states to impose additional restrictions.

Federal Noxious Weeds State noxious-weed seed requirements recognized in the adminstration of the Federal Seed Act (USDA, 2025):
💧 Aquatic and wetland weeds: mosquito fern or water velvet (Azolla pinnata), killer algae, Mediterranean strain (Caulerpa taxifolia), water hyacinth relative (Eichhornia azurea), hydrilla (Hydrilla verticillata), water-spinach or swamp morning-glory (Ipomoea aquatica), waterweed (Lagarosiphon major), ambulia (Limnophila sessiliflora), melaleuca or paperbark (Melaleuca quinquenervia), Monochoria species (Monochoria hastata, M. vaginalis), ottelia (Ottelia alismoides), arrowhead (Sagittaria sagittifolia), Salvinia species (Salvinia auriculata, S. biloba, S. herzogii, S. molesta), wetland nightshade (Solanum tampicense), and exotic bur-reed (Sparganium erectum).

Parasitic weeds: Aeginetia species (Aeginetia spp.), Alectra species (Alectra spp.), dodders (Cuscuta spp.), broomrapes (Orobanche spp.), and witchweeds (Striga spp.).

Terrestrial weeds: gum arabic tree or thorny acacia (Acacia nilotica), crofton weed (Ageratina adenophora, A. riparia), sessile joyweed (Alternanthera sessilis), capeweed (Arctotheca calendula), onionweed (Asphodelus fistulosus), animated oat or wild oat (Avena sterilis, including A. ludoviciana), wild safflower (Carthamus oxyacantha), pilipiliula (Chrysopogon aciculatus), Benghal dayflower (Commelina benghalensis), common crupina (Crupina vulgaris), African couchgrass or fingergrass (Digitaria abyssinica), velvet fingergrass or annual couchgrass (Digitaria velutina), lightning weed (Drymaria arenariodes), devil’s thorn (Emex spinosa), false caper or Geraldton carnation weed (Euphorbia terracina), goatsrue (Galega officinalis), giant hogweed (Heracleum mantegazzianum), Brazilian satintail (Imperata brasiliensis), cogongrass (Imperata cylindrica), British elecampane or British yellowhead (Inula britannica), murainograss (Ischaemum rugosum), African boxthorn (Lycium ferocissimum), maidenhair creeper (Lygodium flexuosum), Old World climbing fern (Lygodium microphyllum), melastoma (Melastoma malabathricum), mile-a-minute (Mikania cordata, M. micrantha), giant sensitive-plant (Mimosa diplotricha), catclaw mimosa (Mimosa pigra var. pigra), Onopordum thistles (Onopordum acaulon, O. illyricum), jointed prickly pear (Opuntia aurantiaca), red rice complex (Oryza longistaminata, O. punctata, O. rufipogon), Kodo-millet (Paspalum scrobiculatum), kikuyugrass (Pennisetum clandestinum), African feathergrass (Pennisetum macrourum), kyasumagrass (Pennisetum pedicellatum), missiongrass or thin napiergrass (Pennisetum polystachion), Prosopis species (Prosopis alpataco, P. argentina, P. articulata, P. burkartii, P. caldenia, P. calingastana, P. campestris, P. castellanosii, P. denudans, P. elata, P. farcta, P. ferox, P. fiebrigii, P. hassleri, P. humilis, P. kuntzei, P. pallida, P. palmeri, P. reptans, P. rojasiana, P. ruizlealii, P. ruscifolia, P. sericantha, P. strombulifera, P. torquata), itchgrass (Rottboellia cochinchinensis), wild blackberry complex (Rubus fruticosus complex) and wild raspberry (Rubus moluccanus), wild sugarcane (Saccharum spontaneum), wormleaf salsola (Salsola vermiculata), South African and Madagascar ragwort (Senecio inaequidens, S. madagascariensis), Spermacoce(Spermacoce alata), turkeyberry (Solanum torvum), tropical soda apple (Solanum viarum), coat buttons (Tridax procumbens), and liverseed grass (Urochloa panicoides).

A little more depth

No new taxa have been added to the Federal Noxious Weed List since 2010, although taxonomic updates have occurred. While the list includes some plants sold in the ornamental and horticultural trades, federal designation limits movement only. For example, cogon grass (Imperata cylindrica) is a Federal Noxious Weed that cannot be imported or moved across state lines, yet it may still be sold within a state if propagated locally, unless state law prohibits its sale. There are 87 terrestrial, 19 aquatic, and 5 parasitic taxa on Federal Noxious Weed List.

The USDA’s Animal and Plant Health Inspection Service (APHIS) serves as the United States’ National Plant Protection Organization under the International Plant Protection Convention (IPPC) and conducts pest and weed risk assessments in accordance with International Standards for Phytosanitary Measures (ISPMs). Weed Risk Assessments (WRAs) are publicly available.

Only plants that meet the U.S. interpretation of quarantine pest under ISPM 5-24 (pp. 25-27) or regulated non-quarantine can be subject to import restrictions (trade barriers). Therefore only high-risk species not yet present are typically placed on the NAPPRA list. There are currently 79 NAPPRA designated plant species; and 207 restricted taxa that may be hosts of other pests. An example of a prohibited plant is dwarf arrowhead (Sagittaria pygmaea) assessed as high-risk for both the U.S. and Canada. By contrast, fig buttercup (Ficaria verna) has also been assessed as a potential major invader across the U.S., but because it has already begun to naturalize in some states, it is considered beyond federal regulatory control and becomes a state problem. This is a widely recognized problem in the international community. (We discuss this issue in our white paper – pp. 19-23; 70).

Below is a summary of invasive plant regulations in the 13 U.S. states (including Alaska) that share a border with Canada. Because invasive plants do not respect political boundaries, understanding regulatory approaches in neighbouring jurisdictions helps identify shared risks. A spreadsheet summarizing plants regulated across these states (as of July 13, 2023) has been  uploaded. While errors may be present, links to primary sources are provided below and on the Canada: Province & Territories Plant Regulations page.

Alaska AK

Regulatory approach

Alaska regulates invasive and noxious plants primarily under the Plant health and quarantine regulations (11 AAC 34), administered by the Alaska Department of Natural Resources (DNR), Division of Agriculture. Within this regulation, the Seed regulations (§ 11 AAC 34.010–11 AAC 34.090) and Pest control provisions (§ 11 AAC 34.100–11 AAC 34.190) establish the framework used to:

  • set seed quality and labelling standards,
  • maintain a noxious weed list governing seeds in commerce, and
  • issue quarantines that prohibit the importation, movement, sale, or distribution of specified plant pests and plant materials
    (Alaska DNR, Plant Quarantine Summary, 2025).

What is regulated

🌱 24 regulated plant seeds — Prohibited and restricted noxious weeds (11 AAC 34.020)

Prohibited (seed regulation):
Russian knapweed (Acroptilon repens), whitetops and its varieties (Cardaria draba, C. pubescens, Lepidium latifolium), Canada thistle (Cirsium arvense), field bindweed (Convolvulus arvensis), quackgrass (Elymus repens), leafy spurge (Euphorbia esula), hempnettle (Galeopsis tetrahit), galinsoga (Galinsoga parviflora), orange hawkweed (Hieracium aurantiacum), blue-flowering lettuce (Lactuca pulchella), purple loosestrife (Lythrum salicaria), Austrian fieldcress (Rorippa austriaca), horsenettle (Solanum carolinense), and perennial sowthistle (Sonchus arvensis).

Restricted (seed contamination thresholds):
wild oats (Avena fatua), seven seeds per pound; mustard (Brassica juncea, Sinapis arvensis), 36 seeds per pound; blue burr (Lappula echinata), 18 seeds per pound; yellow toadflax (Linaria vulgaris), one seed per pound; buckhorn plantain (Plantago sp.), 90 seeds per pound; annual bluegrass (Poa annua), 90 seeds per pound; wild buckwheat (Polygonum convolvulus), two seeds per pound; radish (Raphanus raphanistrum), 27 seeds per pound; and tufted vetch (Vicia cracca), two seeds per pound.

⚠️ Important clarification:
Alaska’s noxious weed provisions regulate seed quality and contamination. They do not generally mandate eradication, control, or prohibit the sale of live plants once species are established in the landscape. This distinguishes Alaska’s approach from weed control acts used in many other jurisdictions.

🌳 2 terrestrial quarantine plants (Quarantine on mayday and chokecherry trees established, 2025)

  • European bird cherry (Prunus padus) & chokecherry (Prunus virginiana)

💧 5 aquatic quarantine plants (Quarantine of aquatic invasive weeds, 2014)

  • Brazilian waterweed (Egeria densa), Canadian waterweed (Elodea canadensis), western waterweed (Elodea nuttallii), hydrilla (Hydrilla verticillata), and Eurasian watermilfoil (Myriophyllum spicatum).

Key point: Alaska relies on quarantine authority under 11 AAC 34 to restrict the entry, transport, sale, and distribution of specified pests. This authority is species- and pathway-specific, not comprehensive.

Key limitations

  • Regulation is fragmented, with no unified invasive plant statute addressing prevention, sales, and post-establishment impacts.
  • Noxious weed rules focus on seed commerce and contamination, not ecological harm or landscape-level spread.
  • Watchlists and rankings lack regulatory force, relying on voluntary compliance and education.

Learn more

The Alaska Center for Conservation Science developed a list of non-native plant species occurring in Alaska. Some have been screened using an invasiveness plant ranking system (Carson et al., 2008). Some of the ornamental plants ranked high-risk include: sneezeweed (Achillea ptarmica), goutweed (Aegopodium podagraria), European alder (Alnus glutinosa), lady’s mantle (Alchemilla mollis, A. monticola), meadow foxtail (Alopecurus pratensis), spineless plumeless thistle (Carduus acanthoides), Siberian pea shrub (Caragana arborescens), brass buttons (Cotula coronopifolia), Scotch broom (Cytisus scoparius), purple foxglove (Digitalis purpurea), knotweeds (Fallopia japonica, F. sachalinensis), ground ivy (Glechoma hederacea), baby’s-breath (Gypsophila paniculata), English ivy (Hedera helix), giant hogweed (Heracleum mantegazzianum), dame’s rocket (Hesperis matronalis), St. John’s wort (Hypericum perforatum), ornamental jewelweed (Impatiens glandulifera), yellow flag iris (Iris pseudacorus), white dead-nettle (Lamium album), oxeye daisy (Leucanthemum vulgare), toadflaxes (Linaria dalmatica, L. vulgaris), Tatarian honeysuckle (Lonicera tatarica), bigleaf lupine (Lupinus polyphyllus subsp. polyphyllus), loosestrifes (Lythrum salicaria, L. virgatum), mints (Mentha piperita, M. spicata), forget-me-nots (Myosotis scorpioides), American white waterlily (Nymphaea odorata), Iceland poppy (Papaver croceum), smartweeds (Persicaria lapathifolia, P. maculosa, P. wallichii), reed canarygrass (Phalaris arundinacea), rugosa rose (Rosa rugosa), bouncingbet (Saponaria officinalis), red campion (Silene dioica), cordgrasses (Spartina spp.), comfrey (Symphytum officinale), common mullein (Verbascum thapsus), and Johnny-jump-up (Viola tricolor).

The Strategic Plan for Invasive Weed & Agricultural Pest Management and Prevention in Alaska (2011) identified the need to improve regulations

Idaho ID

Regulatory Overview

Within Idaho’s Agricultural and Horticultural Statutes (Title 22), invasive plants are regulated under an Invasive Species Act (C.19) and a Noxious Weeds regulation ( C. 24). Both statutes are administered by the Idaho Department of Agriculture under the Rules Governing Invasive Species and Noxious (IDAPA 02.06.09).

The Invasive Species Act regulates a limited number of high-risk plants associated with bioenergy or trap-cropping systems and prohibits their cultivation, transport, or release without a permit. Additional invasive plants are regulated under the Noxious Weeds Law, which applies more broadly to agricultural, horticultural, aquatic, and natural systems. No article containing noxious weed propagules may be sold within the state of Idaho.

What is regulated

🌱 7 invasive tax are regulated under the Invasive Species Act

  • Regulated energy crops include giant reed (Arundo donax and hybrids), cold-tolerant eucalypts (Eucalyptus spp. and hybrids), purging nut (Jatropha curcas and hybrids), Chinese silvergrass (Miscanthus × giganteus and hybrids), and kudzu (Pueraria montana and hybrids).
  • Regulated trap crops include black nightshade (Solanum nigrum and hybrids) and litchi tomato (Solanum sisymbriifoliumand hybrids).

🌱 ~74 invasive tax are regulated as Noxious Weeds

  • Prohibited genera include all plants and plant parts, including all subtaxa, within the genera Cytisus, Genista, Spartium, and Chamaecytisus.
  • Early Detection and Rapid Response (EDRR): feathered mosquito fern (Azolla pinnata), fanwort (Cabomba caroliniana), purple starthistle (Centaurea calcitrapa), Iberian starthistle (Centaurea iberica), squarrose knapweed (Centaurea triumfettii), Brazilian elodea (Egeria densa), water hyacinth (Eichhornia crassipes), goatsrue (Galega officinalis), giant hogweed (Heracleum mantegazzianum), yellow devil hawkweed (Hieracium glomeratum), tall hawkweed (Hieracium piloselloides), hydrilla (Hydrilla verticillata), common/European frogbit (Hydrocharis morsus-ranae), cogongrass (Imperata cylindrica), policeman’s helmet (Impatiens glandulifera), variable-leaf milfoil (Myriophyllum heterophyllum), starry stonewort (Nitellopsis obtusa), yellow floating heart (Nymphoides peltata), giant salvinia (Salvinia molesta), water chestnut (Trapa natans), and Syrian beancaper (Zygophyllum fabago).
  • Control-listed species: Russian knapweed (Acroptilon repens), small bugloss (Anchusa arvensis), flowering rush (Butomus umbellatus), Turkish thistle (Carduus cinereus), musk thistle (Carduus nutans), meadow knapweed (Centaurea debeauxii), common crupina (Crupina vulgaris), Scotch broom (Cytisus scoparius), viper’s bugloss (Echium vulgare), orange hawkweed (Hieracium aurantiacum), yellow hawkweed (Hieracium caespitosum), black henbane (Hyoscyamus niger), dyer’s woad (Isatis tinctoria), parrotfeather milfoil (Myriophyllum aquaticum), Eurasian watermilfoil (Myriophyllum spicatum and hybrids), matgrass (Nardus stricta), common reed (phragmites) (Phragmites australis), Bohemian knotweed (Polygonum × bohemicum), Japanese knotweed (Polygonum cuspidatum), giant knotweed (Polygonum sachalinense), Mediterranean sage (Salvia aethiopis), perennial sowthistle (Sonchus arvensis), and Johnsongrass (Sorghum halepense).
  • Containment-listed species: jointed goatgrass (Aegilops cylindrica), hoary alyssum (Berteroa incana), white bryony (Bryonia alba), whitetop or hoary cress (Cardaria draba), plumeless thistle (Carduus acanthoides), diffuse knapweed (Centaurea diffusa), yellow starthistle (Centaurea solstitialis), spotted knapweed (Centaurea stoebe), rush skeletonweed (Chondrilla juncea), Canada thistle (Cirsium arvense), poison hemlock (Conium maculatum), field bindweed (Convolvulus arvensis), houndstongue (Cynoglossum officinale), leafy spurge (Euphorbia esula), yellow flag iris (Iris pseudocorus), oxeye daisy (Leucanthemum vulgare), perennial pepperweed (Lepidium latifolium), Dalmatian toadflax (Linaria dalmatica ssp. dalmatica), yellow toadflax (Linaria vulgaris), purple loosestrife (Lythrum salicaria), milium (Milium vernale), Scotch thistle (Onopordum acanthium), curlyleaf pondweed (Potamogeton crispus), tansy ragwort (Senecio jacobaea), saltcedar (Tamarix spp.), and puncturevine (Tribulus terrestris).

💧 ~25 Noxious Weed could be considered aquatic or wetland-associated species

  • Feathered mosquito fern (Azolla pinnata), fanwort (Cabomba caroliniana), Brazilian elodea (Egeria densa), water hyacinth (Eichhornia crassipes), hydrilla (Hydrilla verticillata), common/European frogbit (Hydrocharis morsus-ranae), cogongrass (Imperata cylindrica), policeman’s helmet (Impatiens glandulifera), variable-leaf milfoil (Myriophyllum heterophyllum), parrotfeather milfoil (Myriophyllum aquaticum), Eurasian watermilfoil (Myriophyllum spicatum and hybrids), starry stonewort (Nitellopsis obtusa), yellow floating heart (Nymphoides peltata), giant salvinia (Salvinia molesta), water chestnut (Trapa natans), flowering rush (Butomus umbellatus), matgrass (Nardus stricta), common reed (phragmites) (Phragmites australis), Bohemian knotweed (Polygonum × bohemicum), Japanese knotweed (Polygonum cuspidatum), giant knotweed (Polygonum sachalinense), yellow flag iris (Iris pseudocorus), purple loosestrife (Lythrum salicaria), curlyleaf pondweed (Potamogeton crispus), and saltcedar (Tamarix spp.).

Maine ME

Regulatory Overview

Maine regulates invasive plants through several legal instruments: noxious-weed seed regulations, invasive-terrestrial plant rules, and an aquatic nuisance plant statute.

The Maine Seed Law (Maine Regulatory Statute 07-103, §1041-1043) establishes labelling requirements and limits the presence of noxious-weed seed. Products must indicate the presence by weight of weed seeds. Primary noxious weeds are prohibited. This is administered under he Dept. of Agriculture, Conservation and Forestry (DACF).

DACF is also responsible for implementing an administrate rule that explicitly regulates the sale of invasive terrestrial plants, entitled Criteria for listing invasive terrestrial plants (Code of Maine Rule. 01-001, c. 273) The rule prohibits the sale, import, export, propagation and distribution of plants that meet invasive criteria. To be listed, a plant must:

  • be non-native to Maine;
  • have the potential for rapid growth, dissemination, and establishment in minimally managed habitats;
  • have the biological potential for widespread dispersion, including dispersal across spatial gaps;
  • have the biological potential to occur in high numbers or large colonies in minimally managed habitats; and
  • have the potential to displace native species in minimally managed habitats.

In addition a Watch List indicates plant with invasive potential that may become prohibited in five years, providing growers and retailers and opportunity to prepare. Plants may also be listed as Special Concern. These plants may be sold with labels that clearly indicate “Invasive Species – Harmful to the Environment.” Labels must also include non-invasive alternatives and provide instructions for preventing the spread of the labeled plant.

A third set of statutes are aimed a preventing the spread of invasive aquatic plants to protect water and navigation. The Dept. of Environmental Protection (DEP) oversees implementation of Aquatic nuisance species control  (M. R. S. 38, §419-C). This regulation prohibits the sale and transport of nuisance aquatic plants. In addition an Interagency Task Force on Invasive Aquatic Plants and Nuisance Species (M.R.S. 30-03 §1871) is required by law to develop an action plant to limit the spread of invasive plants and oversee control.

The Maine Horticultural Program ensures that healthy plant material is sold within and exported out of the state. Web portals provide Invasive Plants Information clearly indicating plants that are prohibited from sale, along with Grower Resources and Licensing and Inspection information. Nurseries are licensed and inspected to prevent the spread of pests and invasive plants ( Horticulture, M.R.S. 07-405 §2213).

What is regulated

🌱 ~15 noxious-weed taxa are regulated under the Maine Seed Law

  • Prohibited: quackgrass (Elymus repens, syn. Agropyron repens), Canada thistle (Cirsium arvense), bindweed (Convolvulus arvensis), nut grass (Cyperus esculentus), and woundwort (Stachys palustris)
  • Regulated: corncockle (Agrostemma githago), wild onion (Allium canadense), wild garlic (Allium vineale), yellow rocket (Barbarea vulgaris), wild mustard (Brassica spp.), dodder (Cuscuta spp.), buckhorn plantain (Plantago lanceolata), wild radish (Raphanus raphanistrum), horsenettle (Solanum carolinense), and perennial sowthistle (Sonchus arvensis)

🌱 ~63 invasive taxa are regulated under Criteria for listing invasive terrestrial plants (one requires labelling)

  • Prohibited: amur maple (Acer ginnala), Norway maple (Acer platanoides), bishop’s weed (Aegopodium podagraria), tree of heaven (Ailanthus altissima), garlic mustard (Alliaria petiolata), European alder (Alnus glutinosa), false indigo bush (Amorpha fruticosa), porcelain berry (Ampelopsis glandulosa), woodland angelica (Angelica sylvestris), wild chervil (Anthriscus sylvestris), Japanese angelica tree (Aralia elata), common mugwort (Artemisia vulgaris), Japanese barberry (Berberis thunbergii), common barberry (Berberis vulgaris), flowering rush (Butomus umbellatus), Asiatic bittersweet (Celastrus orbiculatus), Russian olive (Elaeagnus angustifolia), autumn olive (Elaeagnus umbellata), burning bush (Euonymus alatus), wintercreeper (Euonymus fortunei), cypress spurge (Euphorbia cyparissias), silver lace vine (Fallopia baldschuanica), Japanese knotweed (Fallopia japonica), fine-leaved sheep fescue (Festuca filiformis), lesser celandine (Ficaria verna), glossy buckthorn (Frangula alnus), yellow hornpoppy (Glaucium flavum), creeping charlie (Glechoma hederacea), reed (great) mannagrass (Glyceria maxima), dame’s rocket (Hesperis matronalis), sea buckthorn (Hippophae rhamnoides), ornamental jewelweed (Impatiens glandulifera), yellow flag iris (Iris pseudacorus), border privet (Ligustrum obtusifolium), common privet (Ligustrum vulgare), Japanese honeysuckle (Lonicera japonica), amur (bush) honeysuckle (Lonicera maackii), Morrow’s honeysuckle (Lonicera morrowii), Tatarian honeysuckle (Lonicera tatarica), dwarf honeysuckle (Lonicera xylosteum), purple loosestrife (Lythrum salicaria), European wand loosestrife (Lythrum virgatum), stiltgrass (Microstegium vimineum), amur silvergrass (Miscanthus sacchariflorus), paulownia / princess tree (Paulownia tomentosa), mile-a-minute (Persicaria perfoliata), fuki / butterbur (Petasites japonicus), reed canary (ribbon) grass (Phalaris arundinacea), amur cork tree (Phellodendron amurense), photinia / Christmas berry (Photinia villosa), common reed (Phragmites australis), golden bamboo (Phyllostachys aurea), yellow grove bamboo (Phyllostachys aureosulcata), white cottonwood / white poplar (Populus alba), Callery / Bradford pear (Pyrus calleryana), creeping buttercup (Ranunculus repens), black locust (Robinia pseudoacacia), multiflora rose (Rosa multiflora), wineberry (Rubus phoenicolasius), cup plant (Silphium perfoliatum), European mountain ash (Sorbus aucuparia), coltsfoot (Tussilago farfara), common valerian (Valeriana officinalis).
  • Special Concern: rugosa rose (Rosa rugosa)
  • Watch List: hardy kiwi (Actinidia arguta), chocolate vine / five-leaf akebia (Akebia quinata), Italian arum (Arum italicum), paper mulberry (Broussonetia papyrifera), butterfly bush (Buddleja davidii), yam-leaved virgin’s bower / sweet autumn clematis (Clematis terniflora), Indian yam (Dioscorea oppositifolia), Chinese yam (Dioscorea polystachya), weeping lovegrass (Eragrostis curvula), queen of the meadow (Filipendula ulmaria), bicolor lespedeza / two-colored bush-clover (Lespedeza bicolor), California privet (Ligustrum ovalifolium), honeyberry / haskap (Lonicera caerulea), ragged robin (Lychnis flos-cuculi / Silene flos-cuculi), white mulberry (Morus alba), sawtooth oak (Quercus acutissima), rugosa rose / beach rose (Rosa rugosa), Ravenna grass / hardy pampas grass (Saccharum ravennae / Tripidium ravennae), sticky sage (Salvia glutinosa), milk thistle (Silybum marianum), Japanese spiraea (Spiraea japonica), sapphire-berry (Symplocos paniculata), Japanese tree lilac (Syringa reticulata), Chinese cedar (Toona sinensis), Siberian elm (Ulmus pumila), linden arrowwood (Viburnum dilatatum), Siebold viburnum (Viburnum sieboldii), Japanese wisteria (Wisteria floribunda), Chinese wisteria (Wisteria sinensis).

💧 ~11 invasive aquatic taxa are prohibited under Aquatic nuisance species control

  • fanwort (Cabomba spp., including but not limited to Cabomba caroliniana), Brazilian elodea (Egeria densa), hydrilla (Hydrilla verticillata), European frog-bit (Hydrocharis morsus-ranae), nonindigenous water-milfoils (Myriophyllum spp., including Myriophyllum heterophyllum, variable-leaf water-milfoil; Myriophyllum spicatum, Eurasian water-milfoil; and Myriophyllum aquaticum, parrot feather), European naiad (Najas minor), yellow floating heart (Nymphoides peltata), curly pondweed (Potamogeton crispus), giant salvinia (Salvinia molesta), water soldier (Stratiotes aloides), water chestnut (Trapa spp., including but not limited to Trapa natans), swollen bladderwort (Utricularia inflata).

Michigan MI

Regulatory Overview

Michigan invasive plant prevention regulations fall within three Acts: Michigan Seed Law Act, Michigan Noxious Weeds Act and Natural Resources and Environmental Protection Act.

As in other states, the Michigan Seed Law Act 329 of 1965 (MCL 286.701–715) ensure seed products are accurately labeled and exclude or restrict seeds from species of noxious weeds (including invasive species) specified in the Seed Law Implementation (Reg. 715) regulation.

The list of noxious-weed seed species associated with the Michigan Seed Law, does not align with the list of noxious weeds regulated under Michigan’s Noxious Weeds Act 247 of 1941 (MCL 247.61–72)  This Act specifies maintenance and control obligations for particular species like invasive giant hogweed (Heracleum mantegazzianum).

The Natural Resources and Environmental Protection Act 451 of 1994 Part 413 (MCL 324.41301–41341) regulates Transgenic and Non-native Species that have the potential to harm human health, or harm natural, agricultural, or silvicultural resources. There are additional special provisions regulating the sale or watercraft movement of aquatic invasive plants (NREPA 324, §324.41325, §324.41329)

Michigan recognizes and discourages the spread of many invasive plants, like tree-of-heaven (Ailanthus altissima) that are not currently not regulated – Invasive Plants.

What is regulated

🌱 Regulated noxious-weed seed taxa defined by Michigan Seed Law Implementation (Mich. Admin. Code R. 285.715)

  • Prohibited: quackgrass (Agropyron repens, syn. Elytrigia repens), plumeless thistle (Carduus acanthoides), musk thistle (Carduus nutans), whitetop, hoary cress, or perennial peppergrass (Cardaria draba, syn. Lepidium draba), Russian knapweed (Centaurea picris), spotted knapweed (Centaurea maculosa, syn. Centaurea stoebe), Canada thistle (Cirsium arvense), bull thistle (Cirsium vulgare), field bindweed (Convolvulus arvensis), hedge bindweed (Convolvulus sepium), dodder (Cuscuta spp.), yellow nutsedge (Cyperus esculentus), leafy spurge (Euphorbia esula), morning glory (Ipomoea spp.), Johnsongrass (Sorghum halepense, including Sorghum almum and seed indistinguishable from Johnsongrass), perennial sowthistle (Sonchus arvensis), horsenettle (Solanum carolinense), puncturevine (Tribulus terrestris), and serrated tussock (Nasella trichotoma).
  • Restricted noxious-weed seed: velvetleaf (Abutilon theophrasti), wild onion (Allium canadense), wild garlic (Allium vineale), wild oat (Avena fatua), yellow rocket (Barbarea vulgaris), hoary alyssum (Berteroa incana), black mustard (Brassica nigra), Indian mustard (Brassica juncea), wild carrot (Daucus carota), jimsonweed (Datura stramonium), buckhorn plantain (Plantago lanceolata), wild radish (Raphanus raphanistrum), curled dock (Rumex crispus), charlock (Sinapis arvensis), giant foxtail (Setaria faberi), bitter nightshade (Solanum dulcamara), black nightshade (Solanum nigrum), eastern black nightshade (Solanum ptychanthum), silverleaf or purple nightshade (Solanum elaeagnifolium), hairy nightshade (Solanum sarrachoides), nightshade complex (Solanum spp., including species with indistinguishable seed), and cocklebur (Xanthium strumarium).

🌱 Regulated noxious weeds requiring control under Michigan Noxious Weed Act (§247.62)

  • Hoary alyssum (Berteroa incana), wild carrot (Daucus carota), bindweed (Convolvulus arvensis), Canada thistle (Cirsium arvense), dodders (any species of Cuscuta), mustards including charlock (Sinapis arvensis), black mustard (Brassica nigra), and Indian mustard (Brassica juncea), poison ivy (Toxicodendron radicans), poison sumac (Toxicodendron vernix, syn. T. vernix), ragweed (Ambrosia artemisiifolia, historically cited as Ambrosia elatior L.), perennial sowthistle (Sonchus arvensis), and giant hogweed (Heracleum mantegazzianum).

🌱 ~20 regulated Invasive taxa are mostly aquatic plants and terrestrial plants that impact wetlands regulated under NREPA, (§324.41301) 💧~19 aquatic taxa*

  • Prohibited: fanwort (Cabomba caroliniana), cylindro (Cylindrospermopsis raciborskii), Brazilian elodea (Egeria densa, syn. Elodea densa), J giant hogweed (Heracleum mantegazzianum), European frogbit (Hydrocharis morsus-ranae), hydrilla (Hydrilla verticillata), African oxygen weed (Lagarosiphon major), parrot’s feather (Myriophyllum aquaticum), starry stonewort (Nitellopsis obtusa), yellow floating heart (Nymphoides peltata), apanese knotweed (Reynoutria japonica syn Fallopia japonica), giant salvinia (Salvinia molesta, S. auriculata, S. biloba, and S. herzogii), and water chestnut (Trapa natans).
  • Restricted: flowering rush (Butomus umbellatus), autumn olive (Elaeagnus umbellata), purple loosestrife (Lythrum salicaria), Eurasian watermilfoil (Myriophyllum spicatum), common reed or phragmites (Phragmites australis), and curly-leaf pondweed (Potamogeton crispus).

Minnesota MN

Regulatory Overview

Invasive plant prevention regulation in Minnesota falls three laws: Minnesota Seed Law (21.80 – 21.92), Minnesota Noxious Weed Law (18.75-18.91) and the Invasive Species law (84D.01-84D.15). The Departments of Agriculture (MDA) and Department of Natural Resources (MDNR) coordinate administration regulated species.

As with other seed laws, the central purpose is to ensure truthful labelling and seed quality. The prohibition or restriction of specified weed seed does reduce the spread of certain invasive plants. Minnesota updates regularly updates its list of Prohibited & Restricted Weed Seeds, 2025. No listed plants are purposely spread through the horticultural trades.

The Noxious Weed Law acknowledges the role of horticulture in spreading invasive plants and makes it illegal to possess, import, purchase, sell, propagate, transport, or introduce prohibited invasive plants (identified by DNR) and restricted noxious weeds (identify by MDA). Prohibited plants explicitly include the Federal Noxious Weed list, Minnesota and Federal Prohibited and Noxious Plants (2024). This law also provides provisions mandating the control of noxious weeds on private property.

Regulated categories – detailed explanation MDA Noxious Weed List (2025) :

  • FN – Federal noxious weed (USDA–APHIS) – all aquatic plants listed as federal noxious weeds (except Ipomoea aquatica) are also listed as prohibited invasive species by the MDNR
  • SN – State noxious weed (MDA): prevent their spread by prohibiting the importation, sale, and transportation of their propagating parts in the state. These include Specially Regulated Plants that may be sold with conditions.
  • RN – Restricted noxious weed (MDA): prevent their spread by prohibiting the importation, sale, and transportation of their propagating parts in the state
  • PS – State prohibited weed seed (MDA)
  • RS – State restricted weed seed (MDA)

The prohibited invasive plant species regulated under the Invasive species statutes (6216.0100 – 6216.0600) are aquatic at this time. All aquatic plants listed as federal noxious weeds (except Ipomoea aquatica) are also listed as prohibited invasive species by the MDNR.

For explanation of laws and current list of Minnesota prohibited and restricted noxious weeds see MDA Noxious Weed List opens in a new browser tab.  Minnesota Statutes 18.75 – 18.91 opens in a new browser tab and 160.23 opens in a new browser tab.

What is regulated

🌱 Regulated noxious-weed seed taxa

  • Prohibited weed seed: Palmer amaranth (Amaranthus palmeri), hemp* (Cannabis sativa), plumeless thistle (Carduus acanthoides), musk thistle (Carduus nutans), Canada thistle (Cirsium arvense), bull thistle (Cirsium vulgare), field bindweed (Convolvulus arvensis), leafy spurge (Euphorbia esula), perennial peppergrass (Lepidium draba), Russian knapweed (Rhaponticum repens), and perennial sowthistle (Sonchus arvensis).
  • Restricted weed seed: quackgrass (Agropyron repens), hoary alyssum (Berteroa incana), dodder (Cuscuta spp.), buckhorn plantain (Plantago lanceolata), wild radish (Raphanus raphanistrum), giant foxtail (Setaria faberi), wild mustard (Sinapis arvensis), horsenettle (Solanum carolinense), eastern black nightshade (Solanum ptycanthum), and field pennycress or Frenchweed*** (Thlaspi arvense).

🌱 Regulated Invasive plants and noxious-weeds, MDA Noxious Weed List

  • 💧Prohibited aquatic invasive plants: mosquito fern or water velvet (Azolla pinnata), flowering rush (Butomus umbellatus), Mediterranean strain killer algae (Caulerpa taxifolia), Australian stonecrop (Crassula helmsii), anchored or rooted water hyacinth (Eichhornia azurea), hydrilla (Hydrilla verticillata), European frog-bit (Hydrocharis morsus-ranae), Indian swampweed or Miramar weed (Hygrophila polysperma), water-spinach or swamp morning-glory (Ipomoea aquatica), African oxygen weed (Lagarosiphon major), ambulia (Limnophila sessiliflora), purple loosestrife (Lythrum salicaria, Lythrum virgatum, including any variety, hybrid, or cultivar), broadleaf paperbark tree (Melaleuca quinquenervia), heart-shaped false pickerelweed (Monochoria hastata), arrowleaf false pickerelweed (Monochoria vaginalis), Eurasian watermilfoil (Myriophyllum spicatum), brittle naiad (Najas minor), starry stonewort (Nitellopsis obtusa), yellow floating heart (Nymphoides peltata), ducklettuce (Ottelia alismoides), common reed, non-native subspecies (Phragmites australis subsp. australis), curly-leaf pondweed (Potamogeton crispus), arrowhead (Sagittaria sagittifolia), Salvinia species including aquarium watermoss and giant salvinia (Salvinia auriculata, S. biloba, S. herzogii, S. molesta), wetland nightshade (Solanum tampicense), exotic bur-reed (Sparganium erectum), water aloe or water soldiers (Stratiotes aloides), and water chestnut (Trapa natans).
  • Prohibited / Eradicate terrestrial plants: Palmer amaranth (Amaranthus palmeri), tree of heaven (Ailanthus altissima), black swallow-wort (Cynanchum louiseae), pale swallow-wort (Cynanchum rossicum), brown knapweed (Centaurea jacea), diffuse knapweed (Centaurea diffusa), yellow starthistle (Centaurea solstitialis), Grecian foxglove (Digitalis lanata), common teasel (Dipsacus fullonum), cutleaf teasel (Dipsacus laciniatus), giant hogweed (Heracleum mantegazzianum), hooked hair hops (formerly Japanese hops) (Humulus japonicus), Dalmatian toadflax (Linaria dalmatica), golden honeysuckle vine (formerly Japanese honeysuckle) (Lonicera japonica), stiltgrass (Microstegium vimineum), Johnsongrass (Sorghum halepense), and red hailstone (Thladiantha dubia).
  • Prohibited / Control terrestrial plants: Common barberry (Berberis vulgaris), narrowleaf bittercress (Cardamine impatiens), plumeless thistle (Carduus acanthoides), round leaf bittersweet (Celastrus orbiculatus), meadow knapweed (Centaurea × moncktonii), spotted knapweed (Centaurea stoebe subsp. micranthos), Canada thistle (Cirsium arvense), poison hemlock (Conium maculatum), leafy spurge (Euphorbia virgata and Euphorbia esula), purple loosestrife (Lythrum salicaria), wild parsnip (Pastinaca sativa, except for non-wild cultivated varieties), non-native phragmites (Phragmites australis subsp. australis), Bohemian knotweed (Polygonum × bohemicum), Japanese knotweed (Polygonum cuspidatum), giant knotweed (Polygonum sachalinense), and common tansy (Tanacetum vulgare).
  • Restricted terrestrial plants: European alder (Alnus glutinosa), garlic mustard (Alliaria petiolata), creeping meadow foxtail (Alopecurus arundinaceus), porcelain berry (Ampelopsis brevipedunculata), Japanese barberry (restricted cultivars only) (Berberis thunbergii), Siberian peashrub (Caragana arborescens; exemption for Green Spires® ‘Jefarb’), wild carrot or Queen Anne’s lace (Daucus carota), autumn olive (Elaeagnus umbellata), winged burning bush (Euonymus alatus), lesser celandine (Ficaria verna), glossy buckthorn (Frangula alnus), Amur honeysuckle (Lonicera maackii), Bell’s honeysuckle (Lonicera × bella), Morrow’s honeysuckle (Lonicera morrowii), Tatarian honeysuckle (Lonicera tatarica), creeping miscanthus (formerly Amur silvergrass) (Miscanthus sacchariflorus), common or European buckthorn (Rhamnus cathartica), black locust (Robinia pseudoacacia), multiflora rose (Rosa multiflora), crown vetch (Securigera varia), and saltcedar (Tamarix ramosissima).
  • Specially regulated terrestrial plants: Amur maple (Acer ginnala), Norway maple, including all cultivars (Acer platanoides), Tatarian maple (Acer tataricum), common butterbur (Petasites hybridus), giant butterbur (Petasites japonicus), Amur corktree (Phellodendron amurense), Callery pear (Pyrus calleryana), rowan or mountain ash (Sorbus aucuparia), and poison ivy (Toxicodendron radicans and T. rydbergii).

Montana MO

Regulatory Overview

Montana ensures the quality of seed through Montana Code Agricultural Seed and Patented Plant Material (80-5-1 – 80-5-6), Noxious Weed Seed Free Forage Act (MCA 80-7-9) and associated Seed Labelling Rules (4.12.30 – 4.12.3115). This prevents the spread of some invasive plants, but does not target plants in the horticultural trades.

Invasive plants and noxious weeds are regulated under Montana Disease, Pest, and Weed Control (80-7-701- 80-7-720); Weed and Pest Control (7-22-21 & – 7-22-41) and associated Designation of Noxious Weeds (4.2.201 – 4.2.210) . These regulations grant authority to the Montana Department of Agriculture for the listing of noxious weeds and specifying the modes of prevention or reduction required. This includes the ability to prohibit of sales.

There is an additional Aquatic Invasive Species Law (80-7-1001-80-7-1031) and associated rule (12.5.706) aimed at preventing the introduction, importation, and infestation of species like Eurasian watermilfoil (Myriophyllum spicatum) (Montana Fish Wildlife an d Parks, AIS Rules).

What is regulated

🌱 Regulated noxious-weed seed taxa – Labeling for agricultural, vegetable, and flower seed must show the name and approximate number of restricted noxious-weed seeds per pound.

  • Jointed goatgrass (Aegilops cylindrica), quackgrass (Agropyron repens), Palmer amaranth (Amaranthus palmeri), wild oat (Avena fatua), dodder (Cuscuta spp.), Persian darnel (Lolium persicum), curly dock (Rumex crispus), perennial sowthistle (Sonchus arvensis).

🌱 Regulated noxious-weed taxa. These categories specify required control measures. PRIORITY 3 plants specifically prohibit sales.

  • PRIORITY 1A:) These weeds require eradication: Yellow starthistle (Centaurea solstitialis)ˌ Dyer’s woad (Isatis tinctoria), common reed (Phragmites australis ssp. australis).
  • PRIORITY 1B: These weeds require eradication or containment and education: rush skeletonweed (Chondrilla juncea); Scotch broom (Cytisus scoparius); purple loosestrife (Lythrum salicaria); knotweed complex (Polygonum cuspidatumˌ P. sachalinenseˌ P. × bohemicumˌ Fallopia japonicaˌ F. sachalinensisˌ F. × bohemicaˌ Reynoutria japonicaˌ R. sachalinensisˌ and R.× bohemica)
  • PRIORITY 2A: These weeds require eradication or containment where less abundant: flowering rush (Butomus umbellatus); blueweed (Echium vulgare); Meadow hawkweed complex (Hieracium caespitosumˌ H. praealtumˌ H. floridundumˌ and Pilosella caespitosa); orange hawkweed (Hieracium aurantiacumˌ Pilosella aurantiaca); Yellowflag iris (Iris pseudacorus); perennial pepperweed (Lepidium latifolium); Eurasian watermilfoil (Myriophyllum spicatum); tall buttercup (Ranunculus acris); tansy ragwort (Senecio jacobaeaˌ Jacobaea vulgaris)
  • PRIORITY 2B: These weeds require control where less abundant. Management shall be prioritized by local weed districts: Russian knapweed (Acroptilon repensˌ Rhaponticum repens); hoary alyssum (Berteroa incana); Canada thistle (Cirsium arvense); leafy spurge (Euphorbia esula); whitetop (Cardaria drabaˌ Lepidium draba); diffuse knapweed (Centaurea diffusa); spotted knapweed (Centaurea stoebe, C. maculosa); oxeye daisy (Chrysanthemum vulgare, Leucanthemum vulgare); field bindweed (Convolvulus arvensis); St. Johnswort (Hypericum perforatum); Dalmatian toadflax (Linaria dalmatica); sulfur cinquefoil (Potentilla recta); houndstongue (Cynoglossum officinale); yellow toadflax (Linaria vulgaris); curlyleaf pondweed (Potamogeton crispus); saltcedar (Tamarix spp.); common tansy (Tanacetum vulgare).
  • PRIORITY 3 REGULATED PLANTS (NOT MONTANA LISTED NOXIOUS WEEDS) These regulated plants have the potential to have significant negative impacts. The plant may not be intentionally spread or sold other than as a contaminant in agricultural products. The state recommends research, education, and prevention to minimize the spread of the regulated plant: cheatgrass (Bromus tectorum); Brazilian waterweed (Egeria densa); Russian olive (Elaeagnus angustifolia); hydrilla (Hydrilla verticillata); parrot feather watermilfoil (Myriophyllum aquaticum or M. brasiliense).

💧Aquatic invasive plants included in the above list.

  • flowering rush (Butomus umbellatus); rush skeletonweed (Chondrilla juncea); Scotch broom (Cytisus scoparius); Brazilian waterweed (Egeria densa); hydrilla (Hydrilla verticillata); yellowflag iris (Iris pseudacorus); purple loosestrife (Lythrum salicaria); parrot feather watermilfoil (Myriophyllum aquaticum or M. brasiliense); Eurasian watermilfoil (Myriophyllum spicatum); common reed (Phragmites australis ssp. australis); knotweed complex (Polygonum cuspidatum, P. sachalinense, P. × bohemicum, Fallopia japonica, F. sachalinensis, F. × bohemica, Reynoutria japonica, R. sachalinensis, and R. × bohemica); curlyleaf pondweed (Potamogeton crispus); saltcedar (Tamarix spp.).

New Hampshire NH

Regulatory Overview

The New Hampsphire Seed Law (433:1) and associated Seed Administrative Rule (Agr. 2200) provide for the regulation of the labeling, sale, offering, or transporting for sale of agricultural, vegetable, flower, tree, and shrub seeds in the state. They are implemented by the NH Department of Agriculture, Markets & Food (DAMF).

The DAMF also oversees regulation of invasive species within the plant industry under an Insect, Pests and Plant Diseases Statute (430:51-58). This enables the state to make it illegal to collect, transport, buy, sell, or release any listed invasive plants. Regulated plants are specified under the rules for Invasive Species code (Ag. 3800).

Aquatic invasive plants are regulated under Water Management and Protection for the Control of marine pollution and aquatic growth (487-16a-b, 18, 24). No exotic aquatic weeds shall be offered for sale, transported, or introduced in the state without a permit. Regulated aquatic weeds are designated in associated rules for Water Quality (Env-Wq 1300). This is overseen by NH Department of Environmental Services (NHDES) .

In 2023, N(NHDAMF) NHDES jointly published a New Hampshire Comprehensive Invasive Plant List.

What is regulated

🌱  Noxious-weed seed taxa regulated under the NH Seed Law

  • Prohibited weed seeds: quackgrass (Agropyron repens); Canada thistle (Cirsium arvense); field bindweed (Convolvulus arvensis); serrated bedstraw (Galium spp.); tussock (Nasella trichotoma).
  • Restricted weed seeds: corncockle (Agrostemma githago); wild onion (Allium canadense); wild garlic (Allium vineale); yellow rocket (Barbarea vulgaris); wild mustard (Brassica spp.); nutsedge (nutgrass) (Cyperus esculentus); dodder (Cuscuta spp.); purple loosestrife (Lythrum salicaria); ribwort plantain (Plantago lanceolata); annual bluegrass (Poa annua); wild radish (Raphanus raphanistrum); horsenettle (Solanum carolinense); perennial sowthistle (Sonchus arvensis).
  • Undesirable grass seed: redtop (Agrostis gigantea); bentgrass (creeping, colonial, velvet) (Agrostis spp.); bermudagrass (Cynodon spp.); orchardgrass (Dactylis glomerata); tall fescue (Festuca arundinacea); meadow fescue (Festuca pratensis); velvetgrass (Holcus lanatus); timothy (Phleum pratense); annual bluegrass (Poa annua); rough bluegrass (Poa trivialis).

🌱  Invasive plant taxa prohibited under Invasive Plants Species Rules 3800

  • Norway maple (Acer platanoides; incl. Acer platanoides var. schwedleri); European black alder (Alnus glutinosa; syn. Alnus alnus, Betula alnus var. glutinosa); tree of heaven (Ailanthus altissima; syn. Ailanthus glandulosa); garlic mustard (Alliaria petiolata; syn. Alliaria alliaria, Alliaria officinalis, Erysimum alliaria, Sisymbrium alliaria); Japanese barberry (Berberis thunbergii); European barberry (Berberis vulgaris); oriental bittersweet (Celastrus orbiculatus); spotted knapweed (Centaurea stoebe subsp. micranthos; syn. Centaurea biebersteinii, C. maculosa misapplied); black swallow-wort (Cynanchum louiseae; syn. Cynanchum nigrum, Vincetoxicum nigrum); pale swallow-wort (Cynanchum rossicum; syn. Vincetoxicum rossicum); autumn olive (Elaeagnus umbellata var. parvifolia; syn. Elaeagnus parvifolia); burning bush (Euonymus alatus; syn. Celastrus alatus); glossy buckthorn (Frangula alnus; syn. Rhamnus frangula); reed sweet grass (Glyceria maxima; syn. Glyceria spectabilis, Molinia maxima); giant hogweed (Heracleum mantegazzianum); dame’s rocket (Hesperis matronalis); ornamental jewelweed (Impatiens glandulifera; syn. Impatiens roylei); water-flag (Iris pseudacorus); perennial pepperweed (Lepidium latifolium; syn. Cardaria latifolia); blunt-leaved privet (Ligustrum obtusifolium; incl. var. leiocalyx); common privet (Ligustrum vulgare); Japanese honeysuckle (Lonicera japonica; syn. Nintooa japonica); Amur honeysuckle (Lonicera maackii); Morrow’s honeysuckle (Lonicera morrowii); Tartarian honeysuckle (Lonicera tatarica); Bella honeysuckle (Lonicera ×bella); moneywort (Lysimachia nummularia); Japanese stilt grass (Microstegium vimineum; syn. Andropogon vimineum, Eulalia viminea); mile-a-minute weed (Persicaria perfoliata; syn. Ampelygonum perfoliatum, Polygonum perfoliatum); kudzu (Pueraria montana var. lobata; syn. Pueraria lobata, Pueraria thunbergiana, Dolichos lobatus); Japanese knotweed (Reynoutria japonica var. japonica; syn. Fallopia japonica, Polygonum cuspidatum); giant knotweed (Reynoutria sachalinensis; syn. Fallopia sachalinensis, Polygonum sachalinense); Bohemian knotweed (Reynoutria ×bohemica; syn. Fallopia ×bohemica); common buckthorn (Rhamnus cathartica); multiflora rose (Rosa multiflora).

💧 Aquatic invasive taxa prohibited under Prohibited Exotic Aquatic Weeds Env-Wq 1303.02

  • Flowering rush (Butomus umbellatus); fanworts (Cabomba spp., incl. Cabomba caroliniana); swamp stonecrop (Crassula helmsii); Brazilian elodea (Egeria densa); great willowherb / hairy willowherb (Epilobium hirsutum); reed sweet grass / manna grass (Glyceria maxima); hydrilla / anacharis (Hydrilla verticillata); frogbit (Hydrocharis morsus-ranae); East Indian hygrophila (Hygrophila polysperma); water spinach (Ipomoea aquatica); yellow iris / yellow flag iris (Iris pseudacorus); African oxygen weed (Lagarosiphon major); ambulia (Limnophila sessiliflora); purple loosestrife (Lythrum salicaria, L. virgatum, L. alatum and cultivars); water fern (Marsilea quadrifolia); water forget-me-not (Myosotis scorpioides); milfoils / featherfoils (Myriophyllum spp., incl. M. heterophyllum, M. spicatum, M. aquaticum); European naiad (Najas minor); yellow floating heart (Nymphoides peltata); common reed (Phragmites australis [syn. P. communis]); curly leaf pondweed (Potamogeton crispus); double flowering arrowhead / Japanese arrowhead / old world arrowhead (Sagittaria japonica); giant sagittaria (Sagittaria sagittifolia); giant salvinia (Salvinia molesta); water chestnuts (Trapa spp.); slender cattail (Typha gracilis); dwarf cattail / Laxman’s cattail (Typha laxmannii); miniature cattail / micro-mini cattail (Typha minima).

New York NY

Regulatory Overview

The New York Consolidated Laws (AGM Chapter 69, §§ 136–142) establish the Inspection and Sale of Seeds law, including the statutory definition of Noxious Weed Seeds and authority to regulate them (1 NYCRR Part 95).

In 2015, 6 NYCRR Part 575 Prohibited and Regulated Invasive Species became effective (March 10, 2015) under the New York State Department of Environmental Conservation, establishing prohibitions and regulations on possession, transport, sale, importation, purchase, and introduction of select invasive species. Regulated species require labels that clearly state: Invasive Species – Harmful to the Environment.

A companion regulation, 6 NYCRR Part 576 Aquatic Invasive Species Spread Prevention, was later adopted to require reasonable precautions to prevent spreading aquatic invasive species via watercraft and related equipment.

New York State licensing laws for nurseries require adherence to invasive species regulations.

In addition, weeds, including invasive plants, may require control under the New York State Property Maintenance Code  (PMCNYS 2025 – §§ 202 & 302.4). But weeds here is broadly defined as Uncultivated vegetation such as grasses, brush, briars, and annual plants, excluding trees and cultivated vegetation, such as shrubs, flowers, gardens, and vegetation used for agricultural purposes. 

🌱 2 noxious weed-seed taxa – Noxious Weed Seeds

  • spurge, leafy (Euphorbia esula)
  • bluegrass, annual (Poa annua) (in lawn seed)

🌱 69 Noxious weeds taxa Prohibited and Regulated Invasive Species 

  • sycamore maple (Acer pseudoplatanus); japanese chaff flower (Achyranthes japonica); garlic mustard (Alliaria petiolata); porcelain berry (Ampelopsis brevipedunculata); wild chervil (Anthriscus sylvestris); japanese angelica tree (Aralia elata); mugwort (Artemisia vulgaris); small carpet grass (Arthraxon hispidus); japanese barberry (Berberis thunbergii); slender false brome (Brachypodium sylvaticum); fanwort (Cabomba caroliniana); narrowleaf bittercress (Cardamine impatiens); oriental bittersweet (Celastrus orbiculatus); spotted knapweed (Centaurea stoebe syn. C. biebersteinii, C. diffusa, C. maculosa misapplied, C. ×psammogena); canada thistle (Cirsium arvense syn. C. setosum, C. incanum, Serratula arvensis); black swallow-wort (Cynanchum louiseae syn. C. nigrum, Vincetoxicum nigrum); pale swallow-wort (Cynanchum rossicum syn. C. medium, Vincetoxicum medium, V. rossicum); chinese yam (Dioscorea polystachya syn. D. batatas); cut-leaf teasel (Dipsacus laciniatus); brazilian waterweed (Egeria densa); autumn olive (Elaeagnus umbellata); cypress spurge (Euphorbia cyparissias); leafy spurge (Euphorbia esula); lesser celandine (Ficaria verna syn. Ranunculus ficaria); smooth buckthorn (Frangula alnus syn. Rhamnus frangula); reed manna grass (Glyceria maxima); giant hogweed (Heracleum mantegazzianum); japanese hops (Humulus japonicus); hydrilla, water thyme (Hydrilla verticillata); european frogbit (Hydrocharis morsus-ranae); cogon grass (Imperata cylindrica syn. I. arundinacea, Lagurus cylindricus); yellow iris (Iris pseudacorus); broad-leaved pepper-grass (Lepidium latifolium); chinese lespedeza (Lespedeza cuneata); border privet (Ligustrum obtusifolium); japanese honeysuckle (Lonicera japonica); amur honeysuckle (Lonicera maackii); morrow’s honeysuckle (Lonicera morrowii); tartarian honeysuckle (Lonicera tatarica); fly honeysuckle (Lonicera × bella); uruguayan primrose-willow (Ludwigia hexapetala syn. L. grandiflora); floating primrose-willow (Ludwigia peploides); garden loosestrife (Lysimachia vulgaris); purple loosestrife (Lythrum salicaria); japanese stilt grass (Microstegium vimineum); marsh dewflower (Murdannia keisak); parrot-feather (Myriophyllum aquaticum); broadleaf water-milfoil (Myriophyllum heterophyllum); broadleaf water-milfoil hybrid (Myriophyllum heterophyllum × M. laxum); eurasian water-milfoil (Myriophyllum spicatum); yellow floating heart (Nymphoides peltata); wavyleaf basketgrass (Oplismenus hirtellus); mile-a-minute weed (Persicaria perfoliata syn. Polygonum perfoliatum); amur cork tree (Phellodendron amurense); common reed grass (Phragmites australis); golden bamboo (Phyllostachys aurea); yellow groove bamboo (Phyllostachys aureosulcata); curly pondweed (Potamogeton crispus); kudzu (Pueraria montana); japanese knotweed (Reynoutria japonica syn. Fallopia japonica, Polygonum cuspidatum); giant knotweed (Reynoutria sachalinensis syn. Fallopia sachalinensis, Polygonum sachalinensis); bohemian knotweed (Reynoutria × bohemica syn. Fallopia × bohemica, Polygonum × bohemica); common buckthorn (Rhamnus cathartica); multiflora rose (Rosa multiflora); wineberry (Rubus phoenicolasius); gray florist’s willow (Salix atrocinerea); cup-plant (Silphium perfoliatum); water chestnut (Trapa natans); beach vitex (Vitex rotundifolia).
  • Regulated plants that require labelling: Norway maple (Acer platanoides); Japanese virgin’s bower (Clematis terniflora); burning bush (Euonymus alatus); winter creeper (Euonymus fortunei)*; Chinese silver grass (Miscanthus sinensis)*; black locust (Robinia pseudoacacia).
  • Exempt cultivars include Berberis thunbergii (‘Aurea’, ‘UCONNBTCP4N’ [Crimson Cutie™], PPAF; ‘UCONNBTB113’ [Lemon Cutie™], PPAF; ‘UCONNBTB048’ [Lemon Glow™], PPAF; ‘UCONNBTB039’ [Mr. Green Genes™], PP 30,128 P3); Miscanthus sinensis (‘My Fair Maiden’, ‘Scout’); and Euonymus fortunei (‘Kewensis’, ‘Vanilla Frosting’). These exemptions apply only to the specifically named cultivars and do not apply to the species as a whole; exemptions are conditional and subject to review should new evidence indicate increased invasive risk.

💧 aquatic and wetland invasive taxa included in Prohibited and Regulated Invasive Species 

  • 💧 wetland species included in the above list: smooth buckthorn (Frangula alnus syn. Rhamnus frangula); reed manna grass (Glyceria maxima); yellow iris (Iris pseudacorus); purple loosestrife (Lythrum salicaria); marsh dewflower (Murdannia keisak); common reed grass (Phragmites australis).
  • 💧 aquatic species included in the above list: fanwort (Cabomba caroliniana); brazilian waterweed (Egeria densa); hydrilla (Hydrilla verticillata); european frogbit (Hydrocharis morsus-ranae); uruguayan primrose-willow (Ludwigia hexapetala syn. L. grandiflora); floating primrose-willow (Ludwigia peploides); parrot-feather (Myriophyllum aquaticum); broadleaf water-milfoil hybrid (Myriophyllum heterophyllum × M. laxum); eurasian water-milfoil (Myriophyllum spicatum); yellow floating heart (Nymphoides peltata); curly pondweed (Potamogeton crispus); water chestnut (Trapa natans).

North Dakota ND

Regulatory Overview

North Dakota regulates seed quality through its state seed laws, which establish standards for purity, labeling, and allowable levels of prohibited and restricted weed seeds in agricultural and forage seed sold in the state. These requirements are set out in NDCC Chapter 4.1-53 (Seeds) and implemented through administrative rules and seed certification programs. Specific lists of prohibited and restricted weed seeds are designated by the State Seed Commissioner through administrative rule and can be found in N. D. Administrative Code § 74-03-01-09, Field Inspection. This provision identifies prohibited noxious weed seeds subject to zero tolerance and restricted noxious weed seeds subject to limitation and labeling. These designations underpin seed inspection, certification, and enforcement and are reflected in the USDA’s State Noxious-Weed Seed Requirements used for Federal Seed Act compliance.

Under North Dakota law, every person is required to “do all things necessary and proper to control the spread of noxious weeds.” This includes preventing seed dispersal and eradicating infestations in accordance with § 4.1-47-01 through § 4.1-47-28 of the North Dakota Century Code, as summarized in the North Dakota Department of Agriculture’s 2025 Noxious Weeds Law and Regulations. No person may distribute, sell, or offer for sale within this state a noxious weed.

The North Dakota Game and Fish Department, with input from members of the Aquatic Invasive Species Committee (AISC), has created a listing of North Dakota aquatic nuisance species (ND ANS).

In North Dakota, aquatic nuisance species are addressed through a pathway-based management frameworkadministered by the North Dakota Game and Fish Department. Under its statutory authority and with input from the Aquatic Invasive Species Committee (AISC), the Department maintains a list of North Dakota aquatic nuisance species and implements measures to reduce their spread. As outlined in North Dakota Administrative Code Chapter 30-01-01, these measures focus on education, monitoring, and inspections, particularly related to watercraft, equipment, and water use activities. This framework emphasizes prevention of spread rather than regulation of plant sales or comprehensive ecosystem-based invasive species control.

🌱 noxious weed-seed taxa

  • Prohibited: absinthe wormwood (Artemisia absinthium); Palmer amaranth (Amaranthus palmeri) – zero tolerance applied; musk thistle (Carduus nutans); Canada thistle (Cirsium arvense); field bindweed (Convolvulus arvensis); diffuse knapweed (Centaurea diffusa); spotted knapweed (Centaurea stoebe subsp. micranthos); yellow starthistle (Centaurea solstitialis) – zero tolerance applied; hound’s-tongue (Cynoglossum officinale); leafy spurge (Euphorbia esula); Dalmatian toadflax (Linaria genistifolia subsp. dalmatica); yellow toadflax (Linaria vulgaris); hoary cress (Lepidium chalepense); purple loosestrife (Lythrum salicaria); purple loosestrife, cultivars (Lythrum virgatum and all cultivars); Russian knapweed (Rhaponticum repens); perennial sowthistle (Sonchus arvensis); saltcedar (Tamarix spp.).
  • Restricted: wild oat (Avena fatua); hedge bindweed (Calystegia sepium); dodder (Cuscuta spp., except Cuscuta coryli); quackgrass (Elymus repens subsp. repens).

🌱 Noxious weed-seed taxa Noxious Weeds Law and Regulations.

  • absinth wormwood (Artemisia absinthium L.); Palmer amaranth (Amaranthus palmeri); musk thistle (Carduus nutans L.); diffuse knapweed (Centaurea diffusa Lam.); Russian knapweed (Centaurea repens L.); spotted knapweed (Centaurea maculosa Lam.); Canada thistle (Cirsium arvense (L.) Scop.); hound’s-tongue (Cynoglossum officinale L.); leafy spurge (Euphorbia esula L.); Dalmatian toadflax (Linaria genistifolia subsp. dalmatica); yellow toadflax (Linaria vulgaris); purple loosestrife (Lythrum salicaria L., Lythrum virgatum L., and all cultivars); saltcedar (Tamarix spp.).

💧 Aquatic invasive taxa regulated as aquatic nuisance species

  • didymo or rock snot (Didymosphenia geminata); Eurasian watermilfoil (Myriophyllum spicatum); curly-leaf pondweed (Potamogeton crispus).

Ohio OH (still working on this)

Regulatory Overview

Effective: January 7, 2018 “In order to protect native plant species andthwart the growth of invasive plant species, 38 plants have been declared invasive in Ohio. No person shall sell, offer for sale, propagate, distribute, import or intentionally cause the dissemination of any invasive plant in the state of Ohio” Rule 901:5-30-01 | Invasive plant species. https://codes.ohio.gov/ohio-administrative-code/rule-901:5-30-01
(A) In order to protect native plant species and thwart the growth of invasive plant species, the director of the Ohio department of agriculture pursuant to section 901.50 of the Revised Code hereby declares the plants listed in paragraphs (A)(1) to (A)(38) of this rule as invasive plants. The invasive plants are first designated by the plant’s botanical name and then by the plants common name. The botanical name is the official designation for the plant.”
“Ohio law prohibits the sale of any agricultural, flower, or vegetable seed containing prohibited noxious-weed seeds. The sale of agricultural seed containing more than 0.25 percent by weight of restricted noxious-weed seeds or bulblets, or more than 2.5 percent of all weed seeds, is also prohibited” Ohio Dept. of Agriculture Noxious Weed Seeds (https://agri.ohio.gov/divisions/plant-health/grain-warehouse-feed-and-seed/noxious-weed-seeds
“Ohio law requires counties, townships and municipalities to cut or destroy all noxious weeds, brush, briers, burrs, and vines growing along roads and streets within their jurisdictions. Cutting of the vegetation must occur every year between June 1 and 20, August 1 and 20, and if necessary, September 1 and 20, or whenever it’s necessary to destroy the vegetation to prevent or eliminate a safety hazard. Ohio Revised Code (O.R.C.) §§ 5579.04 and 5579.08.” https://farmoffice.osu.edu/sites/aglaw/files/site-library/NoxiousWeedLawBulletin.pdf

(Applicable code for management: Section 5579.04 | Destruction of brush, briers, weeds, and thistles along highways. Section 5579.05 | Notice to destroy weeds. Section 5579.08 | Cutting of briers, brush, and noxious weeds. )

Rule 901:5-37-01 | Prohibited noxious weeds. Ohio Administrative Code /901:5 /Chapter 901:5-37 | Noxious Weeds https://codes.ohio.gov/ohio-administrative-code/rule-901:5-37-01
Removal of noxious weeds is complaint driven Section 5579.05 | Notice to destroy weeds. Ohio Revised Code /Title 55 Roads-Highways-Bridges /Chapter 5579 General Highway Provisions https://codes.ohio.gov/ohio-revised-code/section-5579.05

🌱  noxious-weed taxa

💧 aquatic invasive taxa

Pennsylvania PA (still working on this)

Regulatory Overview

Noxious weeds are identified as a plant that is determined to be injurious to public health, crops, livestock, agricultural land or other property and cannot be sold, transported, planted, or otherwise propagated in Pennsylvania. Weeds are placed within one of three classes, Class A, B, or C based on spread and eradication potential and includes the the Federal Noxious Weed list by default as Class C weeds.  Class C is an interesting category as it includes plants “not known to exist in Pennsylvania but pose a potential threat if introduced and those listed on the Federal Noxious Weed List.”
“No person may research, market, distribute, transport, cultivate, hold, retail, wholesale, propagate or display a noxious weed or controlled plant without obtaining a permit from the department in accordance with the provisions of this chapter” (AGRICULTURE CODE (3 PA.C.S.) –CONTROLLED PLANTS AND NOXIOUS WEEDS Act of Oct. 30, 2017, P.L. 774, No. 46)
Controlled Plant List:
https://www.agriculture.pa.gov/Plants_Land_Water/PlantIndustry/NIPPP/Pages/Controlled-Plant-Noxious-Weed.aspx

Invasive plants management by the Pennsylvania Dept. of Conservation and Natural Resources – DCNR has deemed these trees, shrubs, vines, herbs, and aquatic plants to be invasive on state lands. The species listed are managed by DCNR staff https://www.dcnr.pa.gov/Conservation/WildPlants/InvasivePlants/InvasivePlantFactSheets/Pages/default.aspx

🌱  noxious-weed taxa

💧 aquatic invasive taxa

Vermont VT (still working on this)

Regulatory Overview

This rule established by the Agency of Agriculture, Food and Markets under the authority granted to the secretary at 6 V.S.A., Chapter 84, ‘Pest Survey, Detection and Management’, and 6 V.S.A., § 1 (a) (10) prohibits the movement, sale, possession, cultivation, and / or distribution plant material classified as a noxious weed.
“Class A Noxious Weed” means any noxious weed that is not native to the State, not currently known to occur in the State on the date of listing, and poses a serious threat to the State.”Class B Noxious Weed” means any noxious weed that is not native to the state, is of limited distribution statewide, and poses a serious threat to the State, or any other designated noxious weed being managed to reduce its occurrence and impact in the State, including those on the Federal Noxious Weed List (7 C.F.R. 360.200).
“This rule prohibits the sale, movement, distribution, and in some cases, possession or cultivation of certain species of plants that have been recognized as invasive in Vermont or adjacent States.The impacts of these plant species on native ecosystems outweigh their value as ornamental plants in the nursery and landscaping trades to the extent that the Agency of Agriculture has banned their sale in an effort to prevent their introduction into as yet uninfested areas, or slow their further spread across the state through commerce.
This rule does not prohibit the possession or cultivation of so called Class B plants already established in ornamental or landscape plantings, and there is no requirement or obligation of landowners or managers to remove B plants where they are already growing. Possession, cultivation, sale, movement, and distribution of Class A plants is prohibited.” https://agriculture.vermont.gov/sites/agriculture/files/documents/PHARM/Plant_Pest/Amended_Weed_Rule_NoxWeedsFaq.pdf
They are listed as: a) Aquatic and Wetland Weeds; b) Parasitic weeds; (c) Terrestrial weeds:
https://agriculture.vermont.gov/sites/agriculture/files/documents/PHARM/Plant_Pest/NoxiousWeedsQuarantine1.pdf

Transport of Aquatic Plant and Animal Species (10  V.S.A. § 1454) “A person shall not transport an aquatic plant, aquatic plant part, or aquatic nuisance species to or from any Vermont water.” https://dec.vermont.gov/watershed/lakes-ponds/aquatic-invasives/laws-and-regs

🌱  noxious-weed taxa

💧 aquatic invasive taxa

Washington WA (still working on this)

Regulatory Overview

RCW 17.10 (Revised Code of Washington) is the state’s basic weed law. WAC Chapter 16-750 includes the state Noxious Weed List. The State’s Noxious Weed List is Organized into Three Classes of Weeds: Class A, B, and C. All Class A Noxious Weeds and many Class B and C noxious weeds are on the Quarantine List.
“It is illegal to transport, buy, sell, or trade any quarantined species. It is also illegal to distribute seed packets, flower seed blends, or ‘wildflower mixes’ that include these plants. Anyone who violates the quarantine restrictions is subject to a civil penalty of up to $5,000 per violation.”
https://www.nwcb.wa.gov/washingtons-noxious-weed-laws
Quarantine List https://www.nwcb.wa.gov/noxious-weed-quarantine-list

Class A = Non-native species that are limited in distribution in Washington. State law requires that these weeds be eradicated.Class B = Non-native species that are either absent from or limited in distribution in some portions of the state but very abundant in other areas. The goals are to contain the plants where they are already widespread and prevent their spread into new areas.Class C = Non-native plants that are already widespread. Counties can choose to enforce control, or they can educate residents about controlling these noxious weeds.
Washington https://cms.agr.wa.gov/getmedia/9e83eb5b-8131-48a9-9066-aa76f077a219/brochureprohibitedplants.pdf

Pacific Northwest Noxious Weed List https://depts.washington.edu/waipc/pnwnoxiousweedlist.shtml(Compares states and provinces)

🌱  noxious-weed taxa

💧 aquatic invasive taxa

Wisconsin WI (still working on this)

Regulatory Overview

The invasive species rule, Wis. Admin. Code NR 40 identifies, classifies, and controls invasive species. Regulation includes the movement of invasive plants or their seeds, either intentionally through planting or unintentionally. The list: https://dnr.wi.gov/topic/invasives/documents/NR40plantlist.pdf The law: https://docs.legis.wisconsin.gov/code/admin_code/nr/001/40.pdf

The invasive species rule creates a comprehensive, science-based system with criteria to classify invasive species into two categories: “prohibited” and “restricted.” With certain exceptions, the transport, possession, transfer and introduction of prohibited species is banned. https://dnr.wisconsin.gov/topic/invasives/classification.html
https://p.widencdn.net/xy4gp3/SS1160

Restricted species are also subject to a ban on transport, transfer and introduction, but possession is allowed https://dnr.wisconsin.gov/topic/invasives/classification.html
List https://dnr.wi.gov/topic/Invasives/documents/nr40lists.pdf

“Noxious weed” means Canada thistle, leafy spurge, field bindweed, any weed designated as a noxious weed by the department of natural resources by rule, and any other weed the governing body of any municipality or the county board of any county by ordinance or resolution declares to be noxious within its respective boundaries.” (66.0407 Noxious weeds.)

Regulated Aquatic Invasive Plants in WI https://www3.uwsp.edu/cnr-ap/UWEXLakes/Documents/programs/CBCW/publications/WT-960.pdf
 Eurasian water milfoil, curly leaf pondweed and purple loosestrife are mentioned in Chapter NR 109 AQUATIC PLANTS: INTRODUCTION, MANUAL REMOVAL AND MECHANICAL CONTROL REGULATIONS https://docs.legis.wisconsin.gov/code/admin_code/nr/100/109/07/2
No person may distribute an invasive aquatic plant, under s. NR 109.07.

🌱  noxious-weed taxa

💧 aquatic invasive taxa