Regulations

Individual invasive plant species are regulated in Illinois primarily through three regulations: the Illinois Exotic Weed Act, the Illinois Injurious Species Rule, IDNR, and the Illinois Noxious Weed Law, IDOA. Collectively, these rules restrict the sale and movement of many invasive plant species and genera.   

Additionally, the movement of weed seeds is regulated by the Illinois Seed Law, IDOA, and the movement of aquatic plant material is regulated by the Illinois Boat Registration and Safety Act, IDNR.

The full rules, laws, and acts for the regulations listed below are available on the Illinois General Assembly website at www.ilga.gov.

Review Unregulated Invasive Species of Concern in Illinois.

It is illegal for anyone to buy, sell, distribute, or plant any parts of the listed species or genus without a permit. Permits would only be for research or the distribution of non-viable parts. Last updated in October 2025.

The Illinois Exotic Weed Act

Illinois Administration Code Database, Title 17 Conservation, Part 1010

Species or Genus Listed
Common and scientific names

• Tree of heaven, Ailanthus altissima
• Garlic mustard, Alliaria petiolata
• Roundleaf bittersweet, Celastrus orbiculatus
• Poison hemlock, Conium maculatum
• Teasels, Dipsacus spp.
• Russian olive, Elaeagnus angustifolia
• Thorny olive, Elaeagnus pungens
• Autumn olive, Elaeagnus umbellata
• Leafy spurge, Euphorbia virgata
• Lesser celandine, Ficaria verna
• Glossy buckthorn, Frangula alnus
• Giant hogweed, Heracleum mantegazzianum
• Sericea lespedeza, Lespedeza cuneata
• Winter honeysuckle, Lonicera fragrantissima
• Japanese honeysuckle, Lonicera japonica
• Amur honeysuckle, Lonicera maackii
• Morrow's honeysuckle, Lonicera morrowii
• Tatarian honeysuckle, Lonicera tatarica
• Purple loosestrife, Lythrum salicaria
• Japanese stiltgrass, Microstegium vimineum
• Amur corktree, Phellodendron amurense
• Kudzu, Pueraria montana
• Callery pear*, Pyrus calleryana
• Japanese knotweed, Reynoutria japonica
• Giant knotweed, Reynoutria sachalinensis
• Bohemian knotweed, Reynoutria x bohemica
• Saw-toothed buckthorn, Rhamnus arguta
• Common buckthorn, Rhamnus cathartica
• Dahurian buckthorn, Rhamnus davurica
• Japanese buckthorn, Rhamnus japonica
• Chinese buckthorn, Rhamnus utilis
• Multiflora rose, Rosa multiflora
• Salt cedars, Tamarix spp.
• Black swallow-wort, Vincetoxicum nigrum
• Pale swallow-wort, Vincetoxicum rossicum

*Callery pear regulations go into effect Jan. 1, 2028. 

General description of legislation: This law, administered by the Director of the Illinois Department of Agriculture, gives county governments the authority and responsibility to survey for, control, and govern the distribution of noxious weeds within their jurisdiction. The law also provides an avenue for the establishment of both a Weed Control Superintendent and Noxious Weed Control Fund within each county. Depending upon the situation, new infestations will be managed by the landowner, by the county, and billed to the landowner, the county and landowner split the costs, or at the expense of the county.

The Illinois Noxious Weed Law

Illinois Administration Code Database

Species Listed
Common and scientific names

• Common ragweed*, Ambrosia artemisiifolia
• Giant ragweed*, Ambrosia trifida
• Marijuana, Cannabis sativa
• Musk thistle, Carduus nutans
• Canada thistle, Cirsium arvense
• Kudzu, Pueraria montana
• Perennial sowthistle, Sonchus arvensis
• Sorghum, Sorghum almum. Includes Johnsongrass X sorghum crosses with rhizomes Johnsongrass
• Johnsongrass, Sorghum halepense

* Within corporate limits of cities, villages, and incorporated towns

General description of legislation: This law, administered by the Illinois Department of Natural Resources, does not only focus on weeds but also regulates injurious animals.  It is illegal for any species on this list to be possessed, propagated, bought, sold, bartered or offered to be bought, sold, bartered, transported, traded, transferred or loaned to any other person or institution unless a permit is first obtained, except persons engaged in interstate transport for lawful commercial purposes who do not buy, sell, barter, trade, transfer, loan or offer to do so in Illinois may transport injurious species across Illinois without an injurious species permit from the Department. 

The Illinois Injurious Species Rule

Species Listed
Common and scientific names

• Mosquito fern, Azolla pinnata
• Flowering rush, Butomus umbellatus
• Mediterranean killer algae, Caulerpa taxifolia
• Brazilian elodea, Egeria densa (syn. Elodea densa, Anacharis densa)
• Anchored water hyacinth, Eichhornia azurea
• Hydrilla, Hydrilla verticillata
• European frogbit, Hydrocharis morsus-ranae
• Miramar weed, Hygrophilia polysperma
• Chinese water spinach, Ipomoea aquatica
• Yellow flag iris, Iris pseudacorus
• Oxygen weed, Lagarosiphon major
• Asian marshweed/ambulia, Limnophila sessiliflora
• Arrowleaf, Monochoria hastata
• Heartshape, Monochoria vaginalis
• Parrot feather, Myriophyllum aquaticum
• Eurasian watermilfoil, Myriophyllum spicatum
• Brittle naiad, Najas minor
• Yellow floating heart, Nymphoides peltata
• Duck lettuce, Ottelia alismoides
• Curlyleaf pondweed, Potamogeton crispus
• Arrowhead, Sagittaria sagittifolia
• Giant salvinia, Salvinia auriculata
• Giant salvinia, Salvinia biloba
• Giant salvinia, Salvinia herzogii
• Giant salvinia, Salvinia molesta
• Exotic bur-reed, Sparganium erectum
• Water soldier, Stratiotes aloides
• Water chestnut, Trapa natans

General Description of Legislation: No person may place or operate a vehicle, seaplane, watercraft, or other object of any kind in waters of this State if it has any aquatic plants or aquatic animals attached to the exterior of the vehicle, seaplane, watercraft, or other object (excluding duckweed).

Boat Registration and Safety Act

Species Listed: All aquatic plants and/or animals, excluding duckweed.

General Description of Legislation: This law includes weed seeds and sections on labeling, storing, and certifying agricultural seeds. It does prohibit the sale or transport of any seeds or seed mixtures that contain any seeds from prohibited (primary) species or that contain seeds from restricted (secondary) species in excess of the proportions of 1 weed seed to 1,000 agricultural seeds. Agricultural seeds that contain greater than 3% weed seeds and total inert matter (20% for bluegrasses, redtop, bentgrasses, orchardgrass, creeping red fescue, and smooth brome) cannot be sold in Illinois.

Illinois Seed Law 

Illinois Administration Code Database

Prohibited (Primary) Species 
Common and scientific names 

• Field bindweed, Convolvulus arvensis
• Hoary cress/whitetop, Cardaria draba
• Johnsongrass, Sorghum halepense. Includes Sorghum almum and all seeds indistinguishable from Johnsongrass
• Russian knapweed, Acroptilon repens (syn. Centaurea picris)
• Perennial sowthistle, Sonchus arvensis
• Leafy spurge, Euphorbia esula
• Canada thistle, Cirsium arvense
• Serrate tussock, Nassella trichotoma

Restricted (Secondary) Species 
Common and scientific names 

• Narrowleaf plantain, Plantago lanceolata
• Carolina horsenettle, Solanum carolinense
• Queen Anne’s lace, Daucus carota
• Oxeye daisy, Leucanthemum vulgare
• Curly dock, Rumex crispus
• Dodders, Cuscuta sp.
• Wild garlic, Allium vineale
• Giant foxtail, Setaria faberi
• Mustards, Brassica juncea, B. kaber (syn. Sinapis arvensis), and B. nigra
• Wild onion/meadow garlic, Allium canadense
• Bird rape, Brassica campestris
• Quackgrass, Elymus repens (syn. Agropyron repens)