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

Oklahoma noxious weeds

Oklahoma (OK) lists 3 plants as noxious weeds under OAC 35:30-33-2. Oklahoma'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 Oklahoma?

Oklahoma names 3 plants, including Canada Thistle, Nodding Plumeless Thistle and Scotch Cottonthistle. A noxious-weed listing obliges control and limits movement; it does not by itself ban nursery sale. 3 of the 3 are also flagged invasive by GRIIS, which is an ecological finding rather than a ruling by Oklahoma. Checked against OAC 35:30-33-2 on July 20, 2026.

Canada Thistle – Cirsium arvense Not recorded hereInvasive

Canada Thistle (Cirsium arvense)
Photo by Richard Bartz, Munich aka Makro Freak / CC BY-SA 2.5 / Wikimedia Commons

Invasive in the US, and recorded in no Oklahoma county. Oklahoma lists Canada Thistle under “noxious weed - prohibited.”

Nodding Plumeless Thistle – Carduus nutans IntroducedInvasive

Nodding Plumeless Thistle (Carduus nutans)
Photo by Andreiflorea993 / CC BY-SA 4.0 / Wikimedia Commons

Invasive in the US, and recorded in 2 of Oklahoma’s 77 counties. Oklahoma lists Nodding Plumeless Thistle under “noxious weed - prohibited.”

Scotch Cottonthistle – Onopordum acanthium Not recorded hereInvasive

Scotch Cottonthistle (Onopordum acanthium)
Photo by penarc / Public domain / Wikimedia Commons

Invasive in the US, and recorded in no Oklahoma county. Oklahoma lists Scotch Cottonthistle under “noxious weed - prohibited.”

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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 ListedInvasiveOklahoma says “noxious weed - prohibited” —
Nodding Plumeless Thistle Carduus nutans ListedInvasiveOklahoma says “noxious weed - prohibited” —
Scotch Cottonthistle Onopordum acanthium ListedInvasiveOklahoma says “noxious weed - prohibited” —

What the tags mean

Two separate findings. Invasive is ecological. The other three are legal statuses Oklahoma 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

Oklahoma listings
OAC 35:30-33-2. 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 Oklahoma’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 Oklahoma

Plants that two or more states bordering Oklahoma regulate, and Oklahoma 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 Oklahoma invasive species list?

Not under that name. Oklahoma's legal list is a noxious-weed list: 3 plants named under OAC 35:30-33-2, 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 all 3 as invasive in the lower 48 states. That is an ecological finding, not a ruling by Oklahoma. This page shows both side by side.

What plants are illegal to sell in Oklahoma?

Oklahoma'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. 3 plants are named under OAC 35:30-33-2. 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 Oklahoma?

Search the table on this page for Oklahoma's legal determination, then look for the Invasive chip beside it, which is a separate ecological finding from GRIIS rather than a ruling by Oklahoma. 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 Oklahoma 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 Oklahoma?

Not necessarily, and the distinction matters. Oklahoma'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. OAC 35:30-33-2 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 Oklahoma?

No. This page reproduces what Oklahoma 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.

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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

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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

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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

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

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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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