Ezina · A field manual for plant care · United StatesVol. I · Ed. 2027 · Proof copy

Illinois invasive plants

Illinois (IL) regulates 33 invasive plants under 17 Ill. Adm. Code 1100.30 (Illinois Exotic Weed Act, 525 ILCS 10). Illinois's list is a trade restriction, which governs what may be sold, propagated, or moved within the state — in plain terms, which plants are illegal to sell here.

Illinois invasive species list

Illinois restricts 33 plants, including Purple Loosestrife, Leafy Spurge and Tree of Heaven. Plants marked Prohibited may not be sold, propagated, or moved within Illinois. 28 of the 33 are also flagged invasive by GRIIS, which is an ecological finding rather than a ruling by Illinois. Checked against 17 Ill. Adm. Code 1100.30 (Illinois Exotic Weed Act, 525 ILCS 10) on August 17, 2026.

Amur Corktree – Phellodendron amurense Not recorded hereInvasive

Amur Corktree (Phellodendron amurense)
Photo by Bruce Marlin / CC BY 3.0 / Wikimedia Commons

Invasive in the US, and recorded in no Illinois county. Illinois lists Amur Corktree as an exotic weed.

Amur Honeysuckle – Lonicera maackii IntroducedInvasive

Amur Honeysuckle (Lonicera maackii)
Photo by Herman, D.E., et al / Public domain / ND State Soil Conservation Committee / via USDA PLANTS

Invasive in the US, and recorded in 15 of Illinois’s 102 counties. Illinois lists Amur Honeysuckle as an exotic weed.

Autumn Olive – Elaeagnus umbellata IntroducedInvasive

Autumn Olive (Elaeagnus umbellata)
Photo by KENPEI / CC BY-SA 3.0 / Wikimedia Commons

Invasive in the US, and recorded in 7 of Illinois’s 102 counties. Illinois lists Autumn Olive as an exotic weed.

Bohemian Knotweed – Polygonum x bohemicum Not recorded hereProhibited

Recorded in no Illinois county. Illinois lists Bohemian Knotweed as an exotic weed.

Callery Pear – Pyrus calleryana IntroducedInvasive

Callery Pear (Pyrus calleryana)
Photo by Bruce Marlin / CC BY 3.0 / Wikimedia Commons

Invasive in the US, and recorded in 1 of Illinois’s 102 counties. Illinois lists Callery Pear as an exotic weed.

Chinese Buckthorn – Rhamnus utilis Not recorded hereProhibited

Recorded in no Illinois county. Illinois lists Chinese Buckthorn as an exotic weed.

Common Buckthorn – Rhamnus cathartica IntroducedInvasive

Common Buckthorn (Rhamnus cathartica)
Photo by Köhler, F. E. (Franz Eugen) / Public domain / Wikimedia Commons

Invasive in the US, and recorded in 24 of Illinois’s 102 counties. Illinois lists Common Buckthorn as an exotic weed.

Dahurian Buckthorn – Rhamnus davurica IntroducedProhibited

Dahurian Buckthorn (Rhamnus davurica)
Photo by Salicyna / CC BY-SA 4.0 / Wikimedia Commons

Recorded in 1 of Illinois’s 102 counties. Illinois lists Dahurian Buckthorn as an exotic weed.

European Swallow-Wort – Cynanchum rossicum Not recorded hereInvasive

European Swallow-Wort (Cynanchum rossicum)
Photo by Epibase / CC BY 3.0 / Wikimedia Commons

Invasive in the US, and recorded in no Illinois county. Illinois lists European Swallow-Wort as an exotic weed.

Fig Buttercup – Ranunculus ficaria IntroducedInvasive

Fig Buttercup (Ranunculus ficaria)
Photo by Michal Osmenda from Brussels, Belgium / CC BY-SA 2.0 / Wikimedia Commons

Invasive in the US, and recorded in 1 of Illinois’s 102 counties. Illinois lists Fig Buttercup as an exotic weed.

Garlic Mustard – Alliaria petiolata IntroducedInvasive

Garlic Mustard (Alliaria petiolata)
Photo by O. Pichard / CC BY-SA 3.0 / Wikimedia Commons

Invasive in the US, and recorded in 25 of Illinois’s 102 counties. Illinois lists Garlic Mustard as an exotic weed.

Giant Hogweed – Heracleum mantegazzianum Not recorded hereInvasive

Giant Hogweed (Heracleum mantegazzianum)
Photo by Lucas Kendall / CC BY-SA 4.0 / Wikimedia Commons

Invasive in the US, and recorded in no Illinois county. Illinois lists Giant Hogweed as an exotic weed.

Giant Knotweed – Polygonum sachalinense IntroducedInvasive

Giant Knotweed (Polygonum sachalinense)
Photo by Velocicaptor at en.wikipedia / Public domain / Wikimedia Commons

Invasive in the US, and recorded in 2 of Illinois’s 102 counties. Illinois lists Giant Knotweed as an exotic weed.

Glossy Buckthorn – Frangula alnus IntroducedInvasive

Glossy Buckthorn (Frangula alnus)
Photo by Sten Porse / CC BY-SA 3.0 / Wikimedia Commons

Invasive in the US, and recorded in 18 of Illinois’s 102 counties. Illinois lists Glossy Buckthorn as an exotic weed.

Japanese Buckthorn – Rhamnus japonica Not recorded hereProhibited

Japanese Buckthorn (Rhamnus japonica)
Photo by Steve Hurst / Public domain / ARS Systematic Botany and Mycology Laboratory / via USDA PLANTS

Recorded in no Illinois county. Illinois lists Japanese Buckthorn as an exotic weed.

Japanese Knotweed – Fallopia japonica (potentially invasive weed) IntroducedInvasive

Japanese Knotweed (Fallopia japonica (potentially invasive weed))
Photo by Elaine Haug / CC0 / Smithsonian Open Access / via USDA PLANTS

Invasive in the US, and recorded in 33 of Illinois’s 102 counties. Illinois lists Japanese Knotweed as an exotic weed.

Kudzu – Pueraria montana IntroducedInvasive

Kudzu (Pueraria montana)
Photo by Schurdl / CC BY-SA 4.0 / Wikimedia Commons

Invasive in the US, and recorded in 8 of Illinois’s 102 counties. Illinois lists Kudzu as an exotic weed.

Leafy Spurge – Euphorbia esula IntroducedInvasive

Leafy Spurge (Euphorbia esula)
Photo by Ivar Leidus / CC BY-SA 3.0 / Wikimedia Commons

Invasive in the US, and recorded in 22 of Illinois’s 102 counties. Illinois lists Leafy Spurge as an exotic weed.

Louise's Swallow-Wort – Cynanchum louiseae IntroducedInvasive

Louise's Swallow-Wort (Cynanchum louiseae)
Photo by Part of a work by Britton, N.L., and A. Brown / Public domain / Wikimedia Commons

Invasive in the US, and recorded in 7 of Illinois’s 102 counties. Illinois lists Louise's Swallow-Wort as an exotic weed.

Morrow's Honeysuckle – Lonicera morrowii IntroducedInvasive

Morrow's Honeysuckle (Lonicera morrowii)
Photo by Easai at English Wikipedia / CC BY-SA 3.0 / Wikimedia Commons

Invasive in the US, and recorded in 8 of Illinois’s 102 counties. Illinois lists Morrow's Honeysuckle as an exotic weed.

Multiflora Rose – Rosa multiflora IntroducedInvasive

Multiflora Rose (Rosa multiflora)
Photo by Famartin / CC BY-SA 4.0 / Wikimedia Commons

Invasive in the US, and recorded in 60 of Illinois’s 102 counties. Illinois lists Multiflora Rose as an exotic weed.

Nepalese Browntop – Microstegium vimineum IntroducedInvasive

Nepalese Browntop (Microstegium vimineum)
Photo by James H. Miller & Ted Bodner, Southern Weed Science Society, Bugwood.org / CC BY 3.0 us / Wikimedia Commons

Invasive in the US, and recorded in 2 of Illinois’s 102 counties. Illinois lists Nepalese Browntop as an exotic weed.

Oriental Bittersweet – Celastrus orbiculatus IntroducedInvasive

Oriental Bittersweet (Celastrus orbiculatus)
Photo by Unknown photographer / Public domain / Wikimedia Commons

Invasive in the US, and recorded in 11 of Illinois’s 102 counties. Illinois lists Oriental Bittersweet as an exotic weed.

Poison Hemlock – Conium maculatum IntroducedInvasive

Poison Hemlock (Conium maculatum)
Photo by William & Wilma Follette. USDA NRCS / Public domain / USDA NRCS Wetland Science Institute (WSI) / via USDA PLANTS

Invasive in the US, and recorded in 64 of Illinois’s 102 counties. Illinois lists Poison Hemlock as an exotic weed.

Purple Loosestrife – Lythrum salicaria IntroducedInvasive

Purple Loosestrife (Lythrum salicaria)
Photo by Ivar Leidus / CC BY-SA 3.0 / Wikimedia Commons

Invasive in the US, and recorded in 26 of Illinois’s 102 counties. Illinois lists Purple Loosestrife as an exotic weed.

Purple-Leaf Japanese Honeysuckle – Lonicera japonica 'Purpurea' IntroducedInvasive

Purple-Leaf Japanese Honeysuckle (Lonicera japonica 'Purpurea')
Photo by W.R. Mattoon / Public domain / USDA Forest Service / via USDA PLANTS

Invasive in the US, and recorded in 50 of Illinois’s 102 counties. Illinois lists Purple-Leaf Japanese Honeysuckle as an exotic weed.

Russian Olive – Elaeagnus angustifolia IntroducedInvasive

Russian Olive (Elaeagnus angustifolia)
Photo by Herman, D.E., et al / Public domain / ND State Soil Conservation Committee / via USDA PLANTS

Invasive in the US, and recorded in 11 of Illinois’s 102 counties. Illinois lists Russian Olive as an exotic weed.

Sericea Lespedeza – Lespedeza cuneata IntroducedInvasive

Sericea Lespedeza (Lespedeza cuneata)
Photo by Dalgial / CC BY-SA 4.0 / Wikimedia Commons

Invasive in the US, and recorded in 41 of Illinois’s 102 counties. Illinois lists Sericea Lespedeza as an exotic weed.

Sharp-Tooth Buckthorn – Rhamnus arguta Not recorded hereProhibited

Recorded in no Illinois county. Illinois lists Sharp-Tooth Buckthorn as an exotic weed.

Silverberry – Elaeagnus pungens Not recorded hereInvasive

Silverberry (Elaeagnus pungens)
Photo by James H. Miller, USDA Forest Service, Bugwood.org / CC BY 3.0 us / Wikimedia Commons

Invasive in the US, and recorded in no Illinois county. Illinois lists Silverberry as an exotic weed.

Sweet Breath of Spring – Lonicera fragrantissima Not recorded hereInvasive

Sweet Breath of Spring (Lonicera fragrantissima)
Photo by Kurt Stüber [1] / CC BY-SA 3.0 / Wikimedia Commons

Invasive in the US, and recorded in no Illinois county. Illinois lists Sweet Breath of Spring as an exotic weed.

Tatarian Honeysuckle – Lonicera tatarica IntroducedInvasive

Tatarian Honeysuckle (Lonicera tatarica)
Photo by dave_7 from Lethbridge, Canada / CC BY 2.0 / Wikimedia Commons

Invasive in the US, and recorded in 26 of Illinois’s 102 counties. Illinois lists Tatarian Honeysuckle as an exotic weed.

Tree of Heaven – Ailanthus altissima IntroducedInvasive

Tree of Heaven (Ailanthus altissima)
Photo by USDA Forest Service / Public domain / USDA Forest Service / via USDA PLANTS

Invasive in the US, and recorded in 67 of Illinois’s 102 counties. Illinois lists Tree of Heaven as an exotic weed.

1 of these listings is phasing in. The species is named in the rule, but the sale ban has not taken effect yet, so Illinois nurseries may still legally sell it today. The dates are shown in the table.

Want to check a plant by photo or county?

Use our “Is it native” tool for free.

Compiled from the rule itself, retrieved August 17, 2026. Law changes; if you spot a listing we have wrong or stale, tell us at support@getezina.com.

The same list as a table
Plant Scientific name Status Plant instead
Amur Corktree Phellodendron amurense ProhibitedInvasiveIllinois says “exotic weed” Western Catalpa, Kentucky Coffeetree, Eastern Black Walnut
Amur Honeysuckle Lonicera maackii ProhibitedInvasiveIllinois says “exotic weed” Rough-Leaf Dogwood, Common Witch Hazel, Smooth Sumac
Autumn Olive Elaeagnus umbellata ProhibitedInvasiveIllinois says “exotic weed” Smooth Sumac, Chickasaw Plum, American Black Elderberry
Bohemian Knotweed Polygonum x bohemicum ProhibitedIllinois says “exotic weed” —
Callery Pear Pyrus calleryana ProhibitedInvasivephasing inIllinois says “exotic weed”propagation January 1, 2028 · sale January 1, 2028 Paper Birch, Sassafras, Pin Cherry
Chinese Buckthorn Rhamnus utilis ProhibitedIllinois says “exotic weed” —
Common Buckthorn Rhamnus cathartica ProhibitedInvasiveIllinois says “exotic weed” Rough-Leaf Dogwood, Common Witch Hazel, Smooth Sumac
Dahurian Buckthorn Rhamnus davurica ProhibitedIllinois says “exotic weed” —
European Swallow-Wort Cynanchum rossicum ProhibitedInvasiveIllinois says “exotic weed” —
Fig Buttercup Ranunculus ficaria ProhibitedInvasiveIllinois says “exotic weed” Mississippi Buttercup, Alkali Buttercup, Longbeak Buttercup
Garlic Mustard Alliaria petiolata ProhibitedInvasiveIllinois says “exotic weed” —
Giant Hogweed Heracleum mantegazzianum ProhibitedInvasiveIllinois says “exotic weed” —
Giant Knotweed Polygonum sachalinense ProhibitedInvasiveIllinois says “exotic weed” —
Glossy Buckthorn Frangula alnus ProhibitedInvasiveIllinois says “exotic weed” Shining Willow, Speckled Alder, Silky Dogwood
Japanese Buckthorn Rhamnus japonica ProhibitedIllinois says “exotic weed” —
Japanese Knotweed Fallopia japonica (potentially invasive weed) ProhibitedInvasiveIllinois says “exotic weed” —
Kudzu Pueraria montana ProhibitedInvasiveIllinois says “exotic weed” Trumpet Honeysuckle, American Wisteria, Riverbank Grape
Leafy Spurge Euphorbia esula ProhibitedInvasiveIllinois says “exotic weed” —
Louise's Swallow-Wort Cynanchum louiseae ProhibitedInvasiveIllinois says “exotic weed” —
Morrow's Honeysuckle Lonicera morrowii ProhibitedInvasiveIllinois says “exotic weed” White Meadowsweet, Sandcherry, American Black Currant
Multiflora Rose Rosa multiflora ProhibitedInvasiveIllinois says “exotic weed” American Black Currant, White Meadowsweet, Sandcherry
Nepalese Browntop Microstegium vimineum ProhibitedInvasiveIllinois says “exotic weed” —
Oriental Bittersweet Celastrus orbiculatus ProhibitedInvasiveIllinois says “exotic weed” American Bittersweet, Trumpet Honeysuckle, Yellow Passionflower
Poison Hemlock Conium maculatum ProhibitedInvasiveIllinois says “exotic weed” —
Purple Loosestrife Lythrum salicaria ProhibitedInvasiveIllinois says “exotic weed” Great St. Johnswort, Canada Goldenrod, Missouri Ironweed
Purple-Leaf Japanese Honeysuckle Lonicera japonica 'Purpurea' ProhibitedInvasiveIllinois says “exotic weed” Trumpet Honeysuckle, Grape Honeysuckle, Trumpet Vine
Russian Olive Elaeagnus angustifolia ProhibitedInvasiveIllinois says “exotic weed” Smooth Sumac, Blackjack Oak, Chickasaw Plum
Sericea Lespedeza Lespedeza cuneata ProhibitedInvasiveIllinois says “exotic weed” —
Sharp-Tooth Buckthorn Rhamnus arguta ProhibitedIllinois says “exotic weed” —
Silverberry Elaeagnus pungens ProhibitedInvasiveIllinois says “exotic weed” —
Sweet Breath of Spring Lonicera fragrantissima ProhibitedInvasiveIllinois says “exotic weed” —
Tatarian Honeysuckle Lonicera tatarica ProhibitedInvasiveIllinois says “exotic weed” American Black Currant, White Meadowsweet, Sandcherry
Tree of Heaven Ailanthus altissima ProhibitedInvasiveIllinois says “exotic weed” Western Catalpa, Kentucky Coffeetree, Post Oak

What the tags mean

Two separate findings. Invasive is ecological. The other three are legal statuses Illinois sets in statute, and which one applies turns on what the rule obliges, and of whom.

Invasive
An ecological finding, and a different question from the law. GRIIS — the Global Register of Introduced and Invasive Species — lists the plant as invasive in the lower 48 states. Most invasive plants carry no state listing at all and are sold freely, so a plant without this tag is not thereby safe, and a plant without a legal chip is not thereby harmless.
Prohibited
May not be sold, moved, propagated or possessed at all.
Restricted
May still be sold or held, but under conditions — retail signage, an identification tag, or a carve-out for sterile cultivars.
Listed
Designated, but the duty to control it falls on landowners rather than on the nursery trade.

Where this comes from

Illinois listings
17 Ill. Adm. Code 1100.30 (Illinois Exotic Weed Act, 525 ILCS 10). Read the rule.
Invasive status
GRIIS, the Global Register of Introduced and Invasive Species, via GBIF, covering the lower 48 states. A scientific register with no legal force; it is cited separately from the statute above because the two disagree far more often than they agree. Garden crops it flags only for spreading from cultivation are left out after review.
Status wording
The Prohibited / Restricted / Listed chips are Ezina’s normalisation across 44 states and are not the legal term. Where Illinois’s own word for a plant differs from the chip, it is quoted verbatim beneath it.
Nativity
USDA PLANTS county distribution layer, surfaced through the county checker.

Regulated next door, but not in Illinois

Plants that two or more states bordering Illinois regulate, and Illinois does not. A listing is a legal act rather than an ecological one, so a plant can be a documented problem here and still be sold here.

Questions

Is there an official Illinois invasive species list?

Yes. 17 Ill. Adm. Code 1100.30 (Illinois Exotic Weed Act, 525 ILCS 10) is Illinois's list, naming 33 plants under a trade restriction, which governs what may be sold, propagated, or moved within the state — in plain terms, which plants are illegal to sell here. GRIIS, the Global Register of Introduced and Invasive Species, flags 28 of these 33 as invasive in the lower 48 states. That is an ecological finding, not a ruling by Illinois. This page shows both side by side.

What plants are illegal to sell in Illinois?

33 plants are regulated under 17 Ill. Adm. Code 1100.30 (Illinois Exotic Weed Act, 525 ILCS 10). Plants marked Prohibited may not be sold, propagated, or moved within Illinois. Plants marked Restricted carry narrower limits set by the rule.

Is my plant invasive in Illinois?

Search the table on this page for Illinois's legal determination, then look for the Invasive chip beside it, which is a separate ecological finding from GRIIS rather than a ruling by Illinois. A plant can carry one, both, or neither. For an address-level answer, enter the plant's name in Ezina's checker to get its Illinois status alongside whether USDA records it as native to your specific county. Every answer links the record it came from.

Is it illegal to plant these in Illinois?

For the plants marked Prohibited, 17 Ill. Adm. Code 1100.30 (Illinois Exotic Weed Act, 525 ILCS 10) bars selling, propagating, or moving them within Illinois. Whether planting one you already own is itself an offence depends on that rule's exact wording, which is why every plant on this page links the citation rather than us paraphrasing it. Plants marked Restricted carry narrower limits the rule sets out.

Does a plant missing from this list mean it is safe to plant in Illinois?

No. This page reproduces what Illinois regulates, and a state list is a legal instrument rather than an ecological verdict. Plenty of plants spread aggressively without ever being listed, and states add species years after the problem is documented.

Grow natives easily with Ezina

How it works

We provide the tools you need to succeed.

The Ezina app identifying a plant: a live camera view framing pink coneflowers, with Plant, Disease/Insect, and Both scan modes.
010.1Identify

Add a plant

Snap a photo or type the name. Ezina matches it to a library of about 40,000 species and starts a care plan tailored to your zone, the local weather, and the time of year.

The Ezina app’s care screen: water needs showing status Okay, last watered 12 days ago, a suggested volume, and a treatment section.
010.2Care

Get a care plan

A schedule built from local rain, temperature, and sun, not a fixed weekly cadence. You get a single notification when a plant actually needs water. Easily add treatments for diseases and pests.

The Ezina Dig planner: a starting-plan site map with suggested garden beds you can draw with your finger.
010.3Plan

Explore new options

Our garden planner Dig helps you understand what works best for your location and makes suggestions based off your long term goals.

Add a plant

Snap a photo or type the name. Ezina matches it to a library of about 40,000 species and starts a care plan tailored to your zone, the local weather, and the time of year.

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Compiled from peer-reviewed research, USDA documentation,
and direct scientific observation across the United States.

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