Canada Thistle – Cirsium arvense IntroducedInvasive
Invasive in the US, and recorded in 3 of Arizona’s 15 counties. Arizona lists Canada Thistle under “Class A.”
Arizona noxious weeds
Arizona (AZ) lists 43 plants as noxious weeds under Ariz. Admin. Code R3-4-245, Tables 4-6. Arizona's list is an agricultural noxious-weed law, which governs control and spread on farmland and rights of way rather than what a nursery may sell.
What plants are invasive in Arizona?
Arizona names 43 plants, including Canada Thistle, Leafy Spurge and Waterthyme. A noxious-weed listing obliges control and limits movement; it does not by itself ban nursery sale. 37 of the 43 are also flagged invasive by GRIIS, which is an ecological finding rather than a ruling by Arizona. Checked against Ariz. Admin. Code R3-4-245, Tables 4-6 on July 20, 2026.
Cantaloupe – Cucumis melo Not recorded hereInvasive
Invasive in the US, and recorded in no Arizona county. Arizona lists Cantaloupe under “Class A.”
Common Water Hyacinth – Eichhornia crassipes IntroducedInvasive
Invasive in the US, and recorded in 1 of Arizona’s 15 counties. Arizona lists Common Water Hyacinth under “Class A.”
Dyer's Woad – Isatis tinctoria Not recorded hereInvasive
Invasive in the US, and recorded in no Arizona county. Arizona lists Dyer's Woad under “Class A.”
Harmal Peganum – Peganum harmala IntroducedInvasive
Invasive in the US, and recorded in 1 of Arizona’s 15 counties. Arizona lists Harmal Peganum under “Class A.”
Kariba-Weed – Salvinia molesta Not recorded hereInvasive
Invasive in the US, and recorded in no Arizona county. Arizona lists Kariba-Weed under “Class A.”
Leafy Spurge – Euphorbia esula IntroducedInvasive
Invasive in the US, and recorded in 1 of Arizona’s 15 counties. Arizona lists Leafy Spurge under “Class A.”
Lenspod Whitetop – Cardaria chalepensis Not recorded hereProhibited
Recorded in no Arizona county. Arizona lists Lenspod Whitetop under “Class A.”
Waterthyme – Hydrilla verticillata IntroducedInvasive
Invasive in the US, and recorded in 1 of Arizona’s 15 counties. Arizona lists Waterthyme under “Class A.”
African Sumac – Searsia lancea Not recorded hereListed
Recorded in no Arizona county. Arizona lists African Sumac under “Class B.”
Asian Mustard – Brassica tournefortii IntroducedInvasive
Invasive in the US, and recorded in 4 of Arizona’s 15 counties. Arizona lists Asian Mustard under “Class B.”
Black Mustard – Brassica nigra IntroducedInvasive
Invasive in the US, and recorded in 5 of Arizona’s 15 counties. Arizona lists Black Mustard under “Class B.”
Bull Thistle – Cirsium vulgare IntroducedInvasive
Invasive in the US, and recorded in 4 of Arizona’s 15 counties. Arizona lists Bull Thistle under “Class B.”
Burningbush – Bassia scoparia IntroducedInvasive
Invasive in the US, and recorded in 5 of Arizona’s 15 counties. Arizona lists Burningbush under “Class C.”
Cheatgrass – Bromus tectorum IntroducedInvasive
Invasive in the US, and recorded in 9 of Arizona’s 15 counties. Arizona lists Cheatgrass under “Class C.”
Common Morning Glory – Ipomoea purpurea IntroducedInvasive
Invasive in the US, and recorded in 10 of Arizona’s 15 counties. Arizona lists Common Morning Glory under “Class C.”
Diffuse Knapweed – Centaurea diffusa IntroducedInvasive
Invasive in the US, and recorded in 1 of Arizona’s 15 counties. Arizona lists Diffuse Knapweed under “Class B.”
Field Bindweed – Convolvulus arvensis IntroducedInvasive
Invasive in the US, and recorded in 15 of Arizona’s 15 counties. Arizona lists Field Bindweed under “Class C.”
Fountain Grass – Pennisetum setaceum IntroducedInvasive
Invasive in the US, and recorded in 4 of Arizona’s 15 counties. Arizona lists Fountain Grass under “Class C.”
Giant Reed – Arundo donax IntroducedInvasive
Invasive in the US, and recorded in 3 of Arizona’s 15 counties. Arizona lists Giant Reed under “Class B.”
Grannyvine – Ipomoea tricolor IntroducedListed
Recorded in 1 of Arizona’s 15 counties. Arizona lists Grannyvine under “Class C.”
Hardheads – Acroptilon repens IntroducedInvasive
Invasive in the US, and recorded in 7 of Arizona’s 15 counties. Arizona lists Hardheads under “Class B.”
Hemp Broomrape – Orobanche ramosa Not recorded hereListed
Recorded in no Arizona county. Arizona lists Hemp Broomrape under “Class B.”
Ivyleaf Morning-Glory – Ipomoea hederacea IntroducedListed
Recorded in 7 of Arizona’s 15 counties. Arizona lists Ivyleaf Morning-Glory under “Class C.”
Johnsongrass – Sorghum halepense IntroducedInvasive
Invasive in the US, and recorded in 15 of Arizona’s 15 counties. Arizona lists Johnsongrass under “Class C.”
Jointed Goatgrass – Aegilops cylindrica IntroducedInvasive
Invasive in the US, and recorded in 5 of Arizona’s 15 counties. Arizona lists Jointed Goatgrass under “Class B.”
Lehmann Lovegrass – Eragrostis lehmanniana IntroducedInvasive
Invasive in the US, and recorded in 5 of Arizona’s 15 counties. Arizona lists Lehmann Lovegrass under “Class C.”
Littlebell – Ipomoea triloba Not recorded hereInvasive
Invasive in the US, and recorded in no Arizona county. Arizona lists Littlebell under “Class C.”
Maltese Star-Thistle – Centaurea melitensis IntroducedInvasive
Invasive in the US, and recorded in 8 of Arizona’s 15 counties. Arizona lists Maltese Star-Thistle under “Class B.”
Nodding Plumeless Thistle – Carduus nutans IntroducedInvasive
Invasive in the US, and recorded in 2 of Arizona’s 15 counties. Arizona lists Nodding Plumeless Thistle under “Class B.”
Onionweed – Asphodelus fistulosus Not recorded hereInvasive
Invasive in the US, and recorded in no Arizona county. Arizona lists Onionweed under “Class B.”
Puncturevine – Tribulus terrestris IntroducedInvasive
Invasive in the US, and recorded in 15 of Arizona’s 15 counties. Arizona lists Puncturevine under “Class C.”
Red Brome – Bromus rubens IntroducedInvasive
Invasive in the US, and recorded in 9 of Arizona’s 15 counties. Arizona lists Red Brome under “Class C.”
Ripgut Brome – Bromus diandrus IntroducedInvasive
Invasive in the US, and recorded in 8 of Arizona’s 15 counties. Arizona lists Ripgut Brome under “Class B.”
Rose Natal Grass – Melinis repens IntroducedInvasive
Invasive in the US, and recorded in 1 of Arizona’s 15 counties. Arizona lists Rose Natal Grass under “Class B.”
Russian Olive – Elaeagnus angustifolia IntroducedInvasive
Invasive in the US, and recorded in 3 of Arizona’s 15 counties. Arizona lists Russian Olive under “Class B.”
Saltlover – Halogeton glomeratus IntroducedInvasive
Invasive in the US, and recorded in 3 of Arizona’s 15 counties. Arizona lists Saltlover under “Class B.”
Scotch Cottonthistle – Onopordum acanthium IntroducedInvasive
Invasive in the US, and recorded in 3 of Arizona’s 15 counties. Arizona lists Scotch Cottonthistle under “Class B.”
Siberian Elm – Ulmus pumila IntroducedInvasive
Invasive in the US, and recorded in 3 of Arizona’s 15 counties. Arizona lists Siberian Elm under “Class B.”
Tree of Heaven – Ailanthus altissima IntroducedInvasive
Invasive in the US, and recorded in 9 of Arizona’s 15 counties. Arizona lists Tree of Heaven under “Class C.”
Whitestar Morning-Glory – Ipomoea x leucantha NativeListed
Recorded in 4 of Arizona’s 15 counties. Arizona lists Whitestar Morning-Glory under “Class C.”
Yellow Bluestem – Bothriochloa ischaemum IntroducedInvasive
Invasive in the US, and recorded in 3 of Arizona’s 15 counties. Arizona lists Yellow Bluestem under “Class B.”
Yellow Star-Thistle – Centaurea solstitialis IntroducedInvasive
Invasive in the US, and recorded in 1 of Arizona’s 15 counties. Arizona lists Yellow Star-Thistle under “Class B.”
No plant on Arizona’s list matches that.
1 of these plant is native to part of the United States, marked US native above. Nativity is regional. Black locust is native to the Appalachians and regulated in New England; Palmer amaranth is native to the Southwest and listed as an agricultural weed in the Corn Belt. A listing tells you what Arizona regulates, not where a plant belongs. The county checker answers the second question.
Want to check a plant by photo or county?
Use our “Is it native” tool for free.Compiled from the rule itself, retrieved July 20, 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 |
|---|---|---|---|
| Canada Thistle | Cirsium arvense | ProhibitedInvasiveArizona says “Class A” | — |
| Cantaloupe | Cucumis melo | ProhibitedInvasiveArizona says “Class A” | — |
| Common Water Hyacinth | Eichhornia crassipes | ProhibitedInvasiveArizona says “Class A” | — |
| Dyer's Woad | Isatis tinctoria | ProhibitedInvasiveArizona says “Class A” | — |
| Harmal Peganum | Peganum harmala | ProhibitedInvasiveArizona says “Class A” | — |
| Kariba-Weed | Salvinia molesta | ProhibitedInvasiveArizona says “Class A” | — |
| Leafy Spurge | Euphorbia esula | ProhibitedInvasiveArizona says “Class A” | — |
| Lenspod Whitetop | Cardaria chalepensis | ProhibitedArizona says “Class A” | — |
| Waterthyme | Hydrilla verticillata | ProhibitedInvasiveArizona says “Class A” | — |
| African Sumac | Searsia lancea | ListedArizona says “Class B” | — |
| Asian Mustard | Brassica tournefortii | ListedInvasiveArizona says “Class B” | — |
| Black Mustard | Brassica nigra | ListedInvasiveArizona says “Class B” | — |
| Bull Thistle | Cirsium vulgare | ListedInvasiveArizona says “Class B” | — |
| Burningbush | Bassia scoparia | ListedInvasiveArizona says “Class C” | — |
| Cheatgrass | Bromus tectorum | ListedInvasiveArizona says “Class C” | — |
| Common Morning Glory | Ipomoea purpurea | ListedInvasiveArizona says “Class C” | — |
| Diffuse Knapweed | Centaurea diffusa | ListedInvasiveArizona says “Class B” | — |
| Field Bindweed | Convolvulus arvensis | ListedInvasiveArizona says “Class C” | — |
| Fountain Grass | Pennisetum setaceum | ListedInvasiveArizona says “Class C” | — |
| Giant Reed | Arundo donax | ListedInvasiveArizona says “Class B” | — |
| Grannyvine | Ipomoea tricolor | ListedArizona says “Class C” | — |
| Hardheads | Acroptilon repens | ListedInvasiveArizona says “Class B” | — |
| Hemp Broomrape | Orobanche ramosa | ListedArizona says “Class B” | — |
| Ivyleaf Morning-Glory | Ipomoea hederacea | ListedArizona says “Class C” | — |
| Johnsongrass | Sorghum halepense | ListedInvasiveArizona says “Class C” | — |
| Jointed Goatgrass | Aegilops cylindrica | ListedInvasiveArizona says “Class B” | — |
| Lehmann Lovegrass | Eragrostis lehmanniana | ListedInvasiveArizona says “Class C” | — |
| Littlebell | Ipomoea triloba | ListedInvasiveArizona says “Class C” | — |
| Maltese Star-Thistle | Centaurea melitensis | ListedInvasiveArizona says “Class B” | — |
| Nodding Plumeless Thistle | Carduus nutans | ListedInvasiveArizona says “Class B” | — |
| Onionweed | Asphodelus fistulosus | ListedInvasiveArizona says “Class B” | — |
| Puncturevine | Tribulus terrestris | ListedInvasiveArizona says “Class C” | — |
| Red Brome | Bromus rubens | ListedInvasiveArizona says “Class C” | — |
| Ripgut Brome | Bromus diandrus | ListedInvasiveArizona says “Class B” | — |
| Rose Natal Grass | Melinis repens | ListedInvasiveArizona says “Class B” | — |
| Russian Olive | Elaeagnus angustifolia | ListedInvasiveArizona says “Class B” | Desert Ironwood, Basin Big Sagebrush, Western Hackberry |
| Saltlover | Halogeton glomeratus | ListedInvasiveArizona says “Class B” | — |
| Scotch Cottonthistle | Onopordum acanthium | ListedInvasiveArizona says “Class B” | — |
| Siberian Elm | Ulmus pumila | ListedInvasiveArizona says “Class B” | Western Cottonwood, Arizona Sycamore, Black Cherry |
| Tree of Heaven | Ailanthus altissima | ListedInvasiveArizona says “Class C” | Western Cottonwood, Arizona Sycamore, Black Cherry |
| Whitestar Morning-Glory US native | Ipomoea x leucantha | ListedArizona says “Class C” | — |
| Yellow Bluestem | Bothriochloa ischaemum | ListedInvasiveArizona says “Class B” | — |
| Yellow Star-Thistle | Centaurea solstitialis | ListedInvasiveArizona says “Class B” | — |
Where this comes from
- Arizona listings
- Ariz. Admin. Code R3-4-245, Tables 4-6. 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 Arizona’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 Arizona
Plants that two or more states bordering Arizona regulate, and Arizona 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.
- Black Henbane Hyoscyamus niger regulated in California, Colorado, Nevada, New Mexico, Utah
- Broadleaved Pepperweed Lepidium latifolium regulated in California, Colorado, Nevada, New Mexico, Utah
- Dalmatian Toadflax Linaria dalmatica regulated in California, Colorado, Nevada, New Mexico, Utah
- Purple Loosestrife Lythrum salicaria regulated in California, Colorado, Nevada, New Mexico, Utah
- Butter and Eggs Linaria vulgaris regulated in Colorado, Nevada, New Mexico, Utah
- Camelthorn Alhagi maurorum regulated in California, Colorado, Nevada, Utah
- Common Crupina Crupina vulgaris regulated in California, Colorado, Nevada, Utah
- Common St. Johnswort Hypericum perforatum regulated in California, Colorado, Nevada, Utah
- Mediterranean Sage Salvia aethiopis regulated in California, Colorado, Nevada, Utah
- Medusahead Taeniatherum caput-medusae regulated in California, Colorado, Nevada, Utah
- Poison Hemlock Conium maculatum regulated in Colorado, Nevada, New Mexico, Utah
- Quackgrass Elymus repens regulated in California, Colorado, New Mexico, Utah
- Red Star-Thistle Centaurea calcitrapa regulated in California, Nevada, New Mexico, Utah
- Rush Skeletonweed Chondrilla juncea regulated in California, Colorado, Nevada, Utah
- Eurasian Watermilfoil Myriophyllum spicatum regulated in Colorado, Nevada, New Mexico
Questions
Is there an official Arizona invasive species list?
Not under that name. Arizona's legal list is a noxious-weed list: 43 plants named under Ariz. Admin. Code R3-4-245, Tables 4-6, an agricultural noxious-weed law, which governs control and spread on farmland and rights of way rather than what a nursery may sell. GRIIS, the Global Register of Introduced and Invasive Species, flags 37 of these 43 as invasive in the lower 48 states. That is an ecological finding, not a ruling by Arizona. This page shows both side by side.
What plants are illegal to sell in Arizona?
Arizona's list is an agricultural noxious-weed law, which governs control and spread on farmland and rights of way rather than what a nursery may sell. 43 plants are named under Ariz. Admin. Code R3-4-245, Tables 4-6. A noxious-weed listing does not automatically ban nursery sale, so check the rule itself before assuming a plant cannot be bought or sold.
Is my plant invasive in Arizona?
Search the table on this page for Arizona's legal determination, then look for the Invasive chip beside it, which is a separate ecological finding from GRIIS rather than a ruling by Arizona. 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 Arizona 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 Arizona?
Not necessarily, and the distinction matters. Arizona's list is an agricultural noxious-weed law: it obliges landowners to control these plants and restricts moving them, rather than making the act of planting one an offence in itself. Ariz. Admin. Code R3-4-245, Tables 4-6 is the text that says what is actually required of you, and it is linked beside every plant here.
Does a plant missing from this list mean it is safe to plant in Arizona?
No. This page reproduces what Arizona 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.
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.
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.
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.
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.
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.
Compiled from peer-reviewed research, USDA documentation,
and direct scientific observation across the United States.