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

Idaho noxious weeds

Idaho (ID) lists 66 plants as noxious weeds under IDAPA 02.06.09.220. Idaho'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 Idaho?

Idaho names 66 plants, including Purple Loosestrife, Canada Thistle and Leafy Spurge. A noxious-weed listing obliges control and limits movement; it does not by itself ban nursery sale. 56 of the 66 are also flagged invasive by GRIIS, which is an ecological finding rather than a ruling by Idaho. Checked against IDAPA 02.06.09.220 on July 20, 2026.

Black Henbane – Hyoscyamus niger IntroducedInvasive

Black Henbane (Hyoscyamus niger)
Photo by Franz Eugen Köhler, Köhler's Medizinal-Pflanzen / Public domain / Wikimedia Commons

Invasive in the US, and recorded in 32 of Idaho’s 44 counties. Idaho lists Black Henbane under “Containment.”

Blood Grass – Imperata cylindrica Not recorded hereInvasive

Blood Grass (Imperata cylindrica)
Photo by No machine-readable author provided. Keisotyo assumed (based on copyright claims). / CC BY-SA 3.0 / Wikimedia Commons

Invasive in the US, and recorded in no Idaho county. Idaho lists Blood Grass under “EDRR.”

Bohemian Knotweed – Polygonum x bohemicum Not recorded hereListed

Recorded in no Idaho county. Idaho lists Bohemian Knotweed under “Containment.”

Brazilian Waterweed – Egeria densa Not recorded hereInvasive

Brazilian Waterweed (Egeria densa)
Photo by Lara Gudmundsdottir / CC BY-SA 4.0 / Wikimedia Commons

Invasive in the US, and recorded in no Idaho county. Idaho lists Brazilian Waterweed under “EDRR.”

Broadleaved Pepperweed – Lepidium latifolium IntroducedInvasive

Broadleaved Pepperweed (Lepidium latifolium)
Photo by Sam Thomas / CC BY 2.0 / Wikimedia Commons

Invasive in the US, and recorded in 29 of Idaho’s 44 counties. Idaho lists Broadleaved Pepperweed under “Control.”

Butter and Eggs – Linaria vulgaris IntroducedInvasive

Butter and Eggs (Linaria vulgaris)
Photo by Ivar Leidus / CC BY-SA 4.0 / Wikimedia Commons

Invasive in the US, and recorded in 41 of Idaho’s 44 counties. Idaho lists Butter and Eggs under “Control.”

Canada Thistle – Cirsium arvense IntroducedInvasive

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 44 of Idaho’s 44 counties. Idaho lists Canada Thistle under “Control.”

Carolina Fanwort – Cabomba caroliniana Not recorded hereListed

Carolina Fanwort (Cabomba caroliniana)
Photo by Leslie J. Mehrhoff, University of Connecticut, Bugwood.org / CC BY 3.0 / Wikimedia Commons

Recorded in no Idaho county. Idaho lists Carolina Fanwort under “EDRR.”

Common Crupina – Crupina vulgaris IntroducedInvasive

Common Crupina (Crupina vulgaris)
Photo by USDA APHIS PPQ Archive, USDA APHIS PPQ, Bugwood.org / CC BY 3.0 us / Wikimedia Commons

Invasive in the US, and recorded in 11 of Idaho’s 44 counties. Idaho lists Common Crupina under “Containment.”

Common Frogbit – Hydrocharis morsus-ranae Not recorded hereInvasive

Common Frogbit (Hydrocharis morsus-ranae)
Photo by Christian Fischer / CC BY-SA 3.0 / Wikimedia Commons

Invasive in the US, and recorded in no Idaho county. Idaho lists Common Frogbit under “EDRR.”

Common Reed – Phragmites australis NativeListed

Common Reed (Phragmites australis)
Photo by Howard, R.A / Public domain / Smithsonian Institution, Richard A. Howard Photograph Collection / via USDA PLANTS

Recorded in 12 of Idaho’s 44 counties. Idaho lists Common Reed under “Containment.”

Common Viper's Bugloss – Echium vulgare IntroducedInvasive

Common Viper's Bugloss (Echium vulgare)
Photo by Kasjanek24 / CC BY-SA 4.0 / Wikimedia Commons

Invasive in the US, and recorded in 9 of Idaho’s 44 counties. Idaho lists Common Viper's Bugloss under “Containment.”

Common Water Hyacinth – Eichhornia crassipes Not recorded hereInvasive

Common Water Hyacinth (Eichhornia crassipes)
Photo by Howard, R.A / Public domain / Smithsonian Institution, Richard A. Howard Photograph Collection / via USDA PLANTS

Invasive in the US, and recorded in no Idaho county. Idaho lists Common Water Hyacinth under “EDRR.”

Curly Pondweed – Potamogeton crispus IntroducedInvasive

Curly Pondweed (Potamogeton crispus)
Photo by Unknown photographer / CC BY-SA 3.0 / Wikimedia Commons

Invasive in the US, and recorded in 7 of Idaho’s 44 counties. Idaho lists Curly Pondweed under “Control.”

Dalmatian Toadflax – Linaria dalmatica IntroducedInvasive

Dalmatian Toadflax (Linaria dalmatica)
Photo by G.A. Cooper / CC0 / Smithsonian Open Access / via USDA PLANTS

Invasive in the US, and recorded in 39 of Idaho’s 44 counties. Idaho lists Dalmatian Toadflax under “Control.”

Diffuse Knapweed – Centaurea diffusa IntroducedInvasive

Diffuse Knapweed (Centaurea diffusa)
Public domain / Wikimedia Commons

Invasive in the US, and recorded in 40 of Idaho’s 44 counties. Idaho lists Diffuse Knapweed under “Control.”

Dyer's Woad – Isatis tinctoria IntroducedInvasive

Dyer's Woad (Isatis tinctoria)
CC BY-SA 3.0 / Wikimedia Commons

Invasive in the US, and recorded in 28 of Idaho’s 44 counties. Idaho lists Dyer's Woad under “Containment.”

Eurasian Watermilfoil – Myriophyllum spicatum Not recorded hereInvasive

Eurasian Watermilfoil (Myriophyllum spicatum)
CC BY-SA 3.0 / Wikimedia Commons

Invasive in the US, and recorded in no Idaho county. Idaho lists Eurasian Watermilfoil under “Containment.”

Feathered Mosquitofern – Azolla pinnata Not recorded hereInvasive

Feathered Mosquitofern (Azolla pinnata)
Photo by Tpa2067 / CC BY-SA 3.0 / Wikimedia Commons

Invasive in the US, and recorded in no Idaho county. Idaho lists Feathered Mosquitofern under “EDRR.”

Field Bindweed – Convolvulus arvensis IntroducedInvasive

Field Bindweed (Convolvulus arvensis)
Photo by Patrick J. Alexander / Public domain / via USDA PLANTS

Invasive in the US, and recorded in 43 of Idaho’s 44 counties. Idaho lists Field Bindweed under “Control.”

Field Sowthistle – Sonchus arvensis IntroducedInvasive

Field Sowthistle (Sonchus arvensis)
Photo by 4028mdk09 / CC BY-SA 3.0 / Wikimedia Commons

Invasive in the US, and recorded in 33 of Idaho’s 44 counties. Idaho lists Field Sowthistle under “Containment.”

Flowering Rush – Butomus umbellatus IntroducedInvasive

Flowering Rush (Butomus umbellatus)
Photo by Howard, R.A / Public domain / Smithsonian Institution, Richard A. Howard Photograph Collection / via USDA PLANTS

Invasive in the US, and recorded in 3 of Idaho’s 44 counties. Idaho lists Flowering Rush under “Containment.”

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 Idaho county. Idaho lists Giant Hogweed under “EDRR.”

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 5 of Idaho’s 44 counties. Idaho lists Giant Knotweed under “Containment.”

Gypsyflower – Cynoglossum officinale IntroducedInvasive

Gypsyflower (Cynoglossum officinale)
Photo by Fornax / CC BY-SA 3.0 / Wikimedia Commons

Invasive in the US, and recorded in 21 of Idaho’s 44 counties. Idaho lists Gypsyflower under “Control.”

Hardheads – Acroptilon repens IntroducedInvasive

Hardheads (Acroptilon repens)
Photo by Steve Hurst / Public domain / ARS Systematic Botany and Mycology Laboratory / via USDA PLANTS

Invasive in the US, and recorded in 42 of Idaho’s 44 counties. Idaho lists Hardheads under “Containment.”

Hoary Alyssum – Berteroa incana IntroducedInvasive

Hoary Alyssum (Berteroa incana)
Photo by Hardyplants at English Wikipedia / Public domain / Wikimedia Commons

Invasive in the US, and recorded in 12 of Idaho’s 44 counties. Idaho lists Hoary Alyssum under “Control.”

Iberian Knapweed – Centaurea iberica Not recorded hereListed

Iberian Knapweed (Centaurea iberica)
Photo by איתן פרמן / CC BY-SA 3.0 / Wikimedia Commons

Recorded in no Idaho county. Idaho lists Iberian Knapweed under “EDRR.”

Japanese Knotweed – Polygonum cuspidatum IntroducedListed

Japanese Knotweed (Polygonum cuspidatum)
Photo by W.carter / CC0 / Wikimedia Commons

Recorded in 18 of Idaho’s 44 counties. Idaho lists Japanese Knotweed under “Containment.”

Johnsongrass – Sorghum halepense IntroducedInvasive

Johnsongrass (Sorghum halepense)
Photo by Forest & Kim Starr / CC BY 3.0 / Wikimedia Commons

Invasive in the US, and recorded in 18 of Idaho’s 44 counties. Idaho lists Johnsongrass under “Containment.”

Jointed Goatgrass – Aegilops cylindrica IntroducedInvasive

Jointed Goatgrass (Aegilops cylindrica)
Photo by Jan Kops / Public domain / Wikimedia Commons

Invasive in the US, and recorded in 31 of Idaho’s 44 counties. Idaho lists Jointed Goatgrass under “Control.”

Kariba-Weed – Salvinia molesta Not recorded hereInvasive

Kariba-Weed (Salvinia molesta)
Photo by No machine-readable author provided. Marshman~commonswiki assumed (based on copyright claims). / CC BY 2.5 / Wikimedia Commons

Invasive in the US, and recorded in no Idaho county. Idaho lists Kariba-Weed under “EDRR.”

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 42 of Idaho’s 44 counties. Idaho lists Leafy Spurge under “Control.”

Matgrass – Nardus stricta IntroducedInvasive

Matgrass (Nardus stricta)
Photo by Conny / CC BY-SA 3.0 / Wikimedia Commons

Invasive in the US, and recorded in 6 of Idaho’s 44 counties. Idaho lists Matgrass under “Containment.”

Meadow Hawkweed – Hieracium caespitosum IntroducedInvasive

Meadow Hawkweed (Hieracium caespitosum)
Photo by Konstantin Ryabitsev from Montréal, Canada / CC BY-SA 2.0 / Wikimedia Commons

Invasive in the US, and recorded in 14 of Idaho’s 44 counties. Idaho lists Meadow Hawkweed under “Containment.”

Meadow Knapweed – Centaurea debeauxii Not recorded hereInvasive

Invasive in the US, and recorded in no Idaho county. Idaho lists Meadow Knapweed under “Containment.”

Mediterranean Sage – Salvia aethiopis IntroducedInvasive

Mediterranean Sage (Salvia aethiopis)
Photo by Eric Coombs, Oregon Department of Agriculture, Bugwood.org / CC BY 3.0 us / Wikimedia Commons

Invasive in the US, and recorded in 5 of Idaho’s 44 counties. Idaho lists Mediterranean Sage under “Containment.”

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 40 of Idaho’s 44 counties. Idaho lists Nodding Plumeless Thistle under “Containment.”

Orange Hawkweed – Hieracium aurantiacum IntroducedInvasive

Orange Hawkweed (Hieracium aurantiacum)
Photo by Norman Melvin / Public domain / USDA NRCS National Wetland Team (NWT) / via USDA PLANTS

Invasive in the US, and recorded in 18 of Idaho’s 44 counties. Idaho lists Orange Hawkweed under “Containment.”

Ornamental Jewelweed – Impatiens glandulifera IntroducedInvasive

Ornamental Jewelweed (Impatiens glandulifera)
Photo by Howard, R.A / Public domain / Smithsonian Institution, Richard A. Howard Photograph Collection / via USDA PLANTS

Invasive in the US, and recorded in 1 of Idaho’s 44 counties. Idaho lists Ornamental Jewelweed under “EDRR.”

Oxeye Daisy – Leucanthemum vulgare IntroducedInvasive

Oxeye Daisy (Leucanthemum vulgare)
Photo by Howard, R.A / Public domain / Smithsonian Institution, Richard A. Howard Photograph Collection / via USDA PLANTS

Invasive in the US, and recorded in 21 of Idaho’s 44 counties. Idaho lists Oxeye Daisy under “Control.”

Parrot Feather Watermilfoil – Myriophyllum aquaticum IntroducedInvasive

Parrot Feather Watermilfoil (Myriophyllum aquaticum)
Photo by Robert H. Mohlenbrock. USDA NRCS / Public domain / USDA NRCS Wetland Science Institute (WSI) / via USDA PLANTS

Invasive in the US, and recorded in 3 of Idaho’s 44 counties. Idaho lists Parrot Feather Watermilfoil under “Containment.”

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 42 of Idaho’s 44 counties. Idaho lists Poison Hemlock under “Control.”

Professor-Weed – Galega officinalis Not recorded hereInvasive

Professor-Weed (Galega officinalis)
CC BY-SA 3.0 / Wikimedia Commons

Invasive in the US, and recorded in no Idaho county. Idaho lists Professor-Weed under “EDRR.”

Puncturevine – Tribulus terrestris IntroducedInvasive

Puncturevine (Tribulus terrestris)
Photo by Patrick J. Alexander / Public domain / via USDA PLANTS

Invasive in the US, and recorded in 34 of Idaho’s 44 counties. Idaho lists Puncturevine under “Control.”

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 29 of Idaho’s 44 counties. Idaho lists Purple Loosestrife under “Control.”

Queen-Devil Hawkweed – Hieracium glomeratum IntroducedListed

Recorded in 1 of Idaho’s 44 counties. Idaho lists Queen-Devil Hawkweed under “EDRR.”

Red Star-Thistle – Centaurea calcitrapa Not recorded hereInvasive

Red Star-Thistle (Centaurea calcitrapa)
Photo by Philmarin / CC BY-SA 3.0 / Wikimedia Commons

Invasive in the US, and recorded in no Idaho county. Idaho lists Red Star-Thistle under “EDRR.”

Rush Skeletonweed – Chondrilla juncea IntroducedInvasive

Rush Skeletonweed (Chondrilla juncea)
Photo by Franz Xaver / CC BY-SA 3.0 / Wikimedia Commons

Invasive in the US, and recorded in 32 of Idaho’s 44 counties. Idaho lists Rush Skeletonweed under “Control.”

Scotch Broom – Cytisus scoparius IntroducedInvasive

Scotch Broom (Cytisus scoparius)
Photo by Danny S. / CC BY-SA 3.0 / Wikimedia Commons

Invasive in the US, and recorded in 11 of Idaho’s 44 counties. Idaho lists Scotch Broom under “Containment.”

Scotch Cottonthistle – Onopordum acanthium IntroducedInvasive

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

Invasive in the US, and recorded in 42 of Idaho’s 44 counties. Idaho lists Scotch Cottonthistle under “Control.”

Small Bugloss – Anchusa arvensis IntroducedListed

Small Bugloss (Anchusa arvensis)
Photo by Britton, N.L., and A. Brown / Public domain / Kentucky Native Plant Society / via USDA PLANTS

Recorded in 5 of Idaho’s 44 counties. Idaho lists Small Bugloss under “Containment.”

Spiny Plumeless Thistle – Carduus acanthoides IntroducedInvasive

Spiny Plumeless Thistle (Carduus acanthoides)
Photo by Howard, R.A / Public domain / Smithsonian Institution, Richard A. Howard Photograph Collection / via USDA PLANTS

Invasive in the US, and recorded in 7 of Idaho’s 44 counties. Idaho lists Spiny Plumeless Thistle under “Control.”

Spotted Knapweed – Centaurea stoebe IntroducedInvasive

Spotted Knapweed (Centaurea stoebe)
Photo by Matt Lavin from Bozeman, Montana, USA / CC BY-SA 2.0 / Wikimedia Commons

Invasive in the US, and recorded in 44 of Idaho’s 44 counties. Idaho lists Spotted Knapweed under “Control.”

Spring Milletgrass – Milium vernale IntroducedListed

Recorded in 9 of Idaho’s 44 counties. Idaho lists Spring Milletgrass under “Control.”

Squarrose Knapweed – Centaurea virgata Not recorded hereListed

Squarrose Knapweed (Centaurea virgata)
(c) Oleg Kosterin, some rights reserved (CC BY) / CC BY 4.0 / Wikimedia Commons

Recorded in no Idaho county. Idaho lists Squarrose Knapweed under “EDRR.”

Stinking Willie – Senecio jacobaea IntroducedInvasive

Stinking Willie (Senecio jacobaea)
Photo by Carl Axel Magnus Lindman / Public domain / Wikimedia Commons

Invasive in the US, and recorded in 14 of Idaho’s 44 counties. Idaho lists Stinking Willie under “Control.”

Syrian Beancaper – Zygophyllum fabago IntroducedInvasive

Syrian Beancaper (Zygophyllum fabago)
Photo by Hurior / Public domain / Wikimedia Commons

Invasive in the US, and recorded in 5 of Idaho’s 44 counties. Idaho lists Syrian Beancaper under “EDRR.”

Tall Hawkweed – Hieracium piloselloides Not recorded hereInvasive

Tall Hawkweed (Hieracium piloselloides)
Photo by Johann Georg Sturm (Painter: Jacob Sturm ) / Public domain / Wikimedia Commons

Invasive in the US, and recorded in no Idaho county. Idaho lists Tall Hawkweed under “EDRR.”

Twoleaf Watermilfoil – Myriophyllum heterophyllum Not recorded hereListed

Twoleaf Watermilfoil (Myriophyllum heterophyllum)
Photo by Robert H. Mohlenbrock. USDA NRCS / Public domain / USDA NRCS Wetland Science Institute (WSI) / via USDA PLANTS

Recorded in no Idaho county. Idaho lists Twoleaf Watermilfoil under “EDRR.”

Water Chestnut – Trapa natans Not recorded hereInvasive

Water Chestnut (Trapa natans)
Photo by Krzysztof Ziarnek, Kenraiz / CC BY-SA 4.0 / Wikimedia Commons

Invasive in the US, and recorded in no Idaho county. Idaho lists Water Chestnut under “EDRR.”

Waterthyme – Hydrilla verticillata Not recorded hereInvasive

Waterthyme (Hydrilla verticillata)
Public domain / Wikimedia Commons

Invasive in the US, and recorded in no Idaho county. Idaho lists Waterthyme under “EDRR.”

White Bryony – Bryonia alba IntroducedInvasive

White Bryony (Bryonia alba)
Photo by Aung / Public domain / Wikimedia Commons

Invasive in the US, and recorded in 16 of Idaho’s 44 counties. Idaho lists White Bryony under “Control.”

Whitetop – Cardaria draba IntroducedInvasive

Whitetop (Cardaria draba)
Photo by Krzysztof Ziarnek, Kenraiz / CC BY-SA 4.0 / Wikimedia Commons

Invasive in the US, and recorded in 41 of Idaho’s 44 counties. Idaho lists Whitetop under “Control.”

Yellow Floatingheart – Nymphoides peltata Not recorded hereInvasive

Yellow Floatingheart (Nymphoides peltata)
Photo by G.A. Cooper / CC0 / Smithsonian Open Access / via USDA PLANTS

Invasive in the US, and recorded in no Idaho county. Idaho lists Yellow Floatingheart under “EDRR.”

Yellow Star-Thistle – Centaurea solstitialis IntroducedInvasive

Yellow Star-Thistle (Centaurea solstitialis)
Photo by Peggy Greb / Public domain / Wikimedia Commons

Invasive in the US, and recorded in 29 of Idaho’s 44 counties. Idaho lists Yellow Star-Thistle under “Control.”

2 of these plants are 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 Idaho 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
Black Henbane Hyoscyamus niger ListedInvasiveIdaho says “Containment” —
Blood Grass Imperata cylindrica ListedInvasiveIdaho says “EDRR” Idaho Bentgrass, Douglas' Sedge, Threadleaf Sedge
Bohemian Knotweed Polygonum x bohemicum ListedIdaho says “Containment” —
Brazilian Waterweed Egeria densa ListedInvasiveIdaho says “EDRR” —
Broadleaved Pepperweed Lepidium latifolium ListedInvasiveIdaho says “Control” —
Butter and Eggs Linaria vulgaris ListedInvasiveIdaho says “Control” —
Canada Thistle Cirsium arvense ListedInvasiveIdaho says “Control” —
Carolina Fanwort US native Cabomba caroliniana ListedIdaho says “EDRR” —
Common Crupina Crupina vulgaris ListedInvasiveIdaho says “Containment” —
Common Frogbit Hydrocharis morsus-ranae ListedInvasiveIdaho says “EDRR” —
Common Reed Phragmites australis ListedIdaho says “Containment” —
Common Viper's Bugloss Echium vulgare ListedInvasiveIdaho says “Containment” —
Common Water Hyacinth Eichhornia crassipes ListedInvasiveIdaho says “EDRR” —
Curly Pondweed Potamogeton crispus ListedInvasiveIdaho says “Control” —
Dalmatian Toadflax Linaria dalmatica ListedInvasiveIdaho says “Control” —
Diffuse Knapweed Centaurea diffusa ListedInvasiveIdaho says “Control” —
Dyer's Woad Isatis tinctoria ListedInvasiveIdaho says “Containment” —
Eurasian Watermilfoil Myriophyllum spicatum ListedInvasiveIdaho says “Containment” —
Feathered Mosquitofern Azolla pinnata ListedInvasiveIdaho says “EDRR” —
Field Bindweed Convolvulus arvensis ListedInvasiveIdaho says “Control” —
Field Sowthistle Sonchus arvensis ListedInvasiveIdaho says “Containment” —
Flowering Rush Butomus umbellatus ListedInvasiveIdaho says “Containment” —
Giant Hogweed Heracleum mantegazzianum ListedInvasiveIdaho says “EDRR” —
Giant Knotweed Polygonum sachalinense ListedInvasiveIdaho says “Containment” —
Gypsyflower Cynoglossum officinale ListedInvasiveIdaho says “Control” —
Hardheads Acroptilon repens ListedInvasiveIdaho says “Containment” —
Hoary Alyssum Berteroa incana ListedInvasiveIdaho says “Control” —
Iberian Knapweed Centaurea iberica ListedIdaho says “EDRR” —
Japanese Knotweed Polygonum cuspidatum ListedIdaho says “Containment” —
Johnsongrass Sorghum halepense ListedInvasiveIdaho says “Containment” —
Jointed Goatgrass Aegilops cylindrica ListedInvasiveIdaho says “Control” —
Kariba-Weed Salvinia molesta ListedInvasiveIdaho says “EDRR” —
Leafy Spurge Euphorbia esula ListedInvasiveIdaho says “Control” —
Matgrass Nardus stricta ListedInvasiveIdaho says “Containment” —
Meadow Hawkweed Hieracium caespitosum ListedInvasiveIdaho says “Containment” —
Meadow Knapweed Centaurea debeauxii ListedInvasiveIdaho says “Containment” —
Mediterranean Sage Salvia aethiopis ListedInvasiveIdaho says “Containment” —
Nodding Plumeless Thistle Carduus nutans ListedInvasiveIdaho says “Containment” —
Orange Hawkweed Hieracium aurantiacum ListedInvasiveIdaho says “Containment” —
Ornamental Jewelweed Impatiens glandulifera ListedInvasiveIdaho says “EDRR” —
Oxeye Daisy Leucanthemum vulgare ListedInvasiveIdaho says “Control” —
Parrot Feather Watermilfoil Myriophyllum aquaticum ListedInvasiveIdaho says “Containment” —
Poison Hemlock Conium maculatum ListedInvasiveIdaho says “Control” —
Professor-Weed Galega officinalis ListedInvasiveIdaho says “EDRR” —
Puncturevine Tribulus terrestris ListedInvasiveIdaho says “Control” —
Purple Loosestrife Lythrum salicaria ListedInvasiveIdaho says “Control” Canada Goldenrod, Cutleaf Waterparsnip, Common Cowparsnip
Queen-Devil Hawkweed Hieracium glomeratum ListedIdaho says “EDRR” —
Red Star-Thistle Centaurea calcitrapa ListedInvasiveIdaho says “EDRR” —
Rush Skeletonweed Chondrilla juncea ListedInvasiveIdaho says “Control” —
Scotch Broom Cytisus scoparius ListedInvasiveIdaho says “Containment” Mallow Ninebark, Sticky Currant, Ninebark
Scotch Cottonthistle Onopordum acanthium ListedInvasiveIdaho says “Control” —
Small Bugloss Anchusa arvensis ListedIdaho says “Containment” —
Spiny Plumeless Thistle Carduus acanthoides ListedInvasiveIdaho says “Control” —
Spotted Knapweed Centaurea stoebe ListedInvasiveIdaho says “Control” —
Spring Milletgrass Milium vernale ListedIdaho says “Control” —
Squarrose Knapweed Centaurea virgata ListedIdaho says “EDRR” —
Stinking Willie Senecio jacobaea ListedInvasiveIdaho says “Control” —
Syrian Beancaper Zygophyllum fabago ListedInvasiveIdaho says “EDRR” —
Tall Hawkweed Hieracium piloselloides ListedInvasiveIdaho says “EDRR” —
Twoleaf Watermilfoil US native Myriophyllum heterophyllum ListedIdaho says “EDRR” —
Water Chestnut Trapa natans ListedInvasiveIdaho says “EDRR” —
Waterthyme Hydrilla verticillata ListedInvasiveIdaho says “EDRR” —
White Bryony Bryonia alba ListedInvasiveIdaho says “Control” —
Whitetop Cardaria draba ListedInvasiveIdaho says “Control” —
Yellow Floatingheart Nymphoides peltata ListedInvasiveIdaho says “EDRR” —
Yellow Star-Thistle Centaurea solstitialis ListedInvasiveIdaho says “Control” —

What the tags mean

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

Idaho listings
IDAPA 02.06.09.220. 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 Idaho’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 Idaho

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

Not under that name. Idaho's legal list is a noxious-weed list: 66 plants named under IDAPA 02.06.09.220, 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 56 of these 66 as invasive in the lower 48 states. That is an ecological finding, not a ruling by Idaho. This page shows both side by side.

What plants are illegal to sell in Idaho?

Idaho'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. 66 plants are named under IDAPA 02.06.09.220. 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 Idaho?

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

Not necessarily, and the distinction matters. Idaho'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. IDAPA 02.06.09.220 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 Idaho?

No. This page reproduces what Idaho 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.

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

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