Flowering shrub

Common ninebark

Physocarpus opulifolius

🌷 Flowering shrubNative in the lower 48

Common ninebark is a popular flowering shrub. It's on our flower lists for 44 states, and across the U.S. it's most often seen in bloom in May–July.

35states

44of our state lists

5,091U.S. sightings*

*iNaturalist research-grade observations, as of October 23, 2026. Planted garden shrubs are mostly excluded from research grade.

On our lists for: Alabama, Alaska, Arkansas, California, Colorado, Connecticut, Delaware, Georgia, Idaho, Illinois, Indiana, Iowa, Kansas, Kentucky, Maine, Maryland, Massachusetts, Michigan, Minnesota, Mississippi, Missouri, Montana, Nebraska, Nevada, New Hampshire, New Jersey, New York, North Carolina, North Dakota, Ohio, Oklahoma, Oregon, Pennsylvania, Rhode Island, South Carolina, South Dakota, Tennessee, Utah, Vermont, Virginia, Washington, West Virginia, Wisconsin, Wyoming

Quick look

Physocarpus opulifolius, known as common ninebark, Eastern ninebark, Atlantic ninebark, or simply ninebark, is a species of flowering plant in the rose family Rosaceae, native to eastern North America, named for its peeling multi-hued bark.
From Wikipedia's article Physocarpus opulifolius, CC BY-SA 4.0.

It belongs to the Rosaceae family. ^iNaturalist
USDA PLANTS describes it as a shrub with a perennial life cycle. ^{USDA PLANTS}
USDA PLANTS lists it as native in the lower 48 states and records it in 35 states. ^{USDA PLANTS}
In Michigan, most iNaturalist sightings of it in flower come in June–July. ^iNaturalist
In Pennsylvania, most iNaturalist sightings of it in flower come in May–June. ^iNaturalist
USDA PLANTS lists its flower color as purple. ^{USDA PLANTS}
USDA PLANTS gives its bloom period as late spring. ^{USDA PLANTS}
USDA PLANTS lists a mature height of about 10 ft. ^{USDA PLANTS}
iNaturalist has 778 research-grade sightings of it in Michigan, ranking #105 among the 172 flowers on our Michigan list. ^iNaturalist
iNaturalist has 661 research-grade sightings of it in Pennsylvania, ranking #111 among the 190 flowers on our Pennsylvania list. ^iNaturalist
iNaturalist has 375 research-grade sightings of it in Ohio, ranking #109 among the 186 flowers on our Ohio list. ^iNaturalist

Common ninebark gift ideas

Handmade common ninebark gifts from independent makers.

🌱 Sample spot. Handmade gift picks from independent shops will appear here once our shop partnership is approved. These cards are placeholders, not real products.

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Common ninebark art print
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Common ninebark greeting card
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Common ninebark mug
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Common ninebark earrings
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Common ninebark embroidery pattern
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Common ninebark sticker
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When does it bloom?

Flowering records by month across the U.S. (iNaturalist research-grade observations marked “Flowering”) (288 records)

Bloom time in each of our 44 states

State	Type	Peak bloom	Sightings*
Michigan	🌷 Garden	June–July	778
Pennsylvania	🌷 Garden	May–June	661
Ohio	🌷 Garden	few records	375
New York	🌷 Garden	few records	359
Minnesota	🌷 Garden	few records	342
Wisconsin	🌷 Garden	few records	331
Virginia	🌷 Garden	few records	315
Illinois	🌷 Garden	few records	264
Maryland	🌷 Garden	few records	192
West Virginia	🌷 Garden	few records	191
North Carolina	🌷 Garden	May–June	190
Maine	🌷 Garden	few records	175
Tennessee	🌷 Garden	few records	168
Vermont	🌷 Garden	few records	157
New Hampshire	🌷 Garden	few records	145
Indiana	🌷 Garden	few records	145
Massachusetts	🌷 Garden	few records	97
Kentucky	🌷 Garden	few records	63
Missouri	🌷 Garden	few records	41
Georgia	🌷 Garden	few records	23
New Jersey	🌷 Garden	few records	20
Arkansas	🌷 Garden	few records	10
Iowa	🌷 Garden	few records	10
Rhode Island	🌷 Garden	few records	10
Alabama	🌷 Garden	few records	7
Connecticut	🌷 Garden	few records	7
Delaware	🌷 Garden	few records	6
Colorado	🌷 Garden	few records	2
South Carolina	🌷 Garden	few records	2
Idaho	🌷 Garden	few records	1
Kansas	🌷 Garden	few records	1
North Dakota	🌷 Garden	few records	1
Utah	🌷 Garden	few records	1
Alaska	🌷 Garden	few records	0
California	🌷 Garden	few records	0
Mississippi	🌷 Garden	few records	0
Montana	🌷 Garden	few records	0
Nebraska	🌷 Garden	few records	0
Nevada	🌷 Garden	few records	0
Oklahoma	🌷 Garden	few records	0
Oregon	🌷 Garden	few records	0
South Dakota	🌷 Garden	few records	0
Washington	🌷 Garden	few records	0
Wyoming	🌷 Garden	few records	0

Conservation status

Federal (U.S. ESA): Not listed No U.S. Endangered Species Act listing in the USFWS ECOS database. ^{USFWS ECOS}
NatureServe global: G5 Secure worldwide. ^NatureServe
Michigan: Not listed Not on Michigan endangered and threatened plants (Mich. Admin. Code R 299.1028, eff. March 20, 2023). NatureServe: SNR, not yet ranked in Michigan. ^{R 299.1028}
Pennsylvania: Not listed Not on Pennsylvania classified native plants (17 Pa. Code Ch. 45, Subchapter B, as amended 2023). NatureServe: S5, secure in Pennsylvania. ^{17 Pa. Code Ch. 45}
Ohio: Not listed Not on Ohio endangered and threatened plants (Ohio Adm. Code 1501:18-1-03, eff. Dec. 26, 2024). NatureServe: SNR, not yet ranked in Ohio. ^{OAC 1501:18-1-03}
New York: Not listed Not on New York protected native plants (6 NYCRR § 193.3). NatureServe: S5, secure in New York. ^{6 NYCRR § 193.3}
Minnesota: Not listed Not on Minnesota endangered, threatened and special concern plants (Minn. R. 6134.0300). NatureServe: SNR, not yet ranked in Minnesota. ^{Minn. R. 6134.0300}
Wisconsin: Not listed Not on Wisconsin endangered and threatened species list (Wis. Admin. Code NR 27.03). NatureServe: SNR, not yet ranked in Wisconsin. ^{NR 27.03}
Virginia: Not listed Not on Virginia endangered and threatened plant and insect species (2VAC5-320-10). NatureServe: S5, secure in Virginia. ^2VAC5-320-10
Illinois: Not listed Not on Illinois List of Endangered and Threatened Flora (17 Ill. Adm. Code 1050), per the Endangered Species Protection Board's 2025 checklist. NatureServe: SNR, not yet ranked in Illinois. ^{IL E&T checklist 2025}
Maryland: Not listed Not on Maryland threatened and endangered plants (COMAR 08.03.08.05, .06 and .08). NatureServe: SNR, not yet ranked in Maryland. ^{COMAR 08.03.08}
West Virginia: No list West Virginia has no state law listing endangered or threatened plants (only federally listed species are protected), so we show NatureServe's West Virginia ranks instead. NatureServe: S4, apparently secure in West Virginia.
North Carolina: Not listed Not on North Carolina Protected Plant Species List (02 NCAC 48F .0301). NatureServe: S4, apparently secure in North Carolina. ^{02 NCAC 48F .0301}
Maine: Not listed Not on Maine Rare Plant List (Maine Natural Areas Program, 2021). E and T are Maine's official endangered and threatened plants (12 M.R.S.); SC and PE are tracking categories. NatureServe: SNA, not applicable (usually because it isn't native there) in Maine. ^{Maine rare plant list}
Tennessee: Not listed Not on Tennessee endangered plants (Tenn. Comp. R. & Regs. 0400-06-02-.04, Rare Plant Protection and Conservation Act). NatureServe: SNR, not yet ranked in Tennessee. ^{TN rule 0400-06-02-.04}
Vermont: Not listed Not on Endangered and Threatened Plants of Vermont (10 V.S.A. chap. 123; list of Feb 10, 2022). NatureServe: SNA, not applicable (usually because it isn't native there) in Vermont. ^{Vermont E&T list}
New Hampshire: Not listed Not on New Hampshire Official Rare Plants List (Ncr 312, eff. Jan 1, 2020). NatureServe: SNR, not yet ranked in New Hampshire. ^{NH Ncr 312}
Indiana: No list Indiana has no state law listing endangered or threatened plants (the DNR keeps a rare plant list, but it isn't regulatory), so we show NatureServe's Indiana ranks instead. NatureServe: SNR, not yet ranked in Indiana.
Massachusetts: Not listed Not on Massachusetts Endangered Species Act list (321 CMR 10.90). NatureServe: SNR, not yet ranked in Massachusetts. ^{MESA list}
Kentucky: Not listed Not on Kentucky endangered and threatened plant lists (400 KAR 3:040, eff. 2026). NatureServe: SNR, not yet ranked in Kentucky. ^{400 KAR 3:040}
Missouri: Not listed Not on Missouri Wildlife Code endangered species (3 CSR 10-4.111), plants. NatureServe: SNR, not yet ranked in Missouri. ^{3 CSR 10-4.111}
Georgia: Not listed Not on Georgia protected plants (Ga. Comp. R. & Regs. 391-4-10-.09; a 2026 update is proposed). NatureServe: S3, vulnerable in Georgia. ^{Ga. R. 391-4-10-.09}
New Jersey: Not listed Not on New Jersey Endangered Plant Species List (N.J.A.C. 7:5C-5.1). NatureServe: S4, apparently secure in New Jersey. ^{N.J.A.C. 7:5C-5.1}
Arkansas: No list Arkansas has no state law listing endangered or threatened plants, so we show NatureServe's Arkansas ranks instead. NatureServe: SNR, not yet ranked in Arkansas.
Iowa: Not listed Not on Iowa endangered, threatened and special concern plants (Iowa Admin. Code r. 571-77.3). NatureServe: S4, apparently secure in Iowa. ^{IAC 571-77.3}
Rhode Island: Not listed Not on Rhode Island Rare Plants 2016 (RI Natural History Survey, from the RI Wildlife Action Plan; informational, Rhode Island has no state plant-protection listing law). NatureServe: SNR, not yet ranked in Rhode Island. ^{RI rare plants 2016}
Alabama: No list Alabama has no state law listing endangered or threatened plants, so we show NatureServe's Alabama ranks instead. NatureServe: SNR, not yet ranked in Alabama.
Connecticut: Not listed Not on Connecticut Endangered, Threatened and Special Concern Plants (RCSA 26-306; 2015 list). NatureServe: SNR, not yet ranked in Connecticut. ^{CT E/T/SC list}
Delaware: Variety listed Only Physocarpus opulifolius var. opulifolius is on Rare and Uncommon Plants of Delaware (DNREC, 2024; informational, Delaware has no state plant-protection list) (sH, historical (informational)). NatureServe: SH, possibly extirpated (known only from historical records) in Delaware. ^{DE rare plants 2024}
Colorado: No list Colorado has no state law listing endangered or threatened plants, so we show NatureServe's Colorado ranks instead. NatureServe: SNR, not yet ranked in Colorado.
South Carolina: No list South Carolina has no state law listing endangered or threatened plants, so we show NatureServe's South Carolina ranks instead. NatureServe: SNR, not yet ranked in South Carolina.
Idaho: No list Idaho has no state law listing endangered or threatened plants, so we show NatureServe's Idaho ranks instead. NatureServe has no Idaho rank for it.
Kansas: No list Kansas's endangered and threatened list (K.A.R. 115-15-1) covers animals only, so we show NatureServe's Kansas ranks for plants. NatureServe: SNR, not yet ranked in Kansas.
North Dakota: No list North Dakota has no state law listing endangered or threatened plants, so we show NatureServe's North Dakota ranks instead. NatureServe: SNR, not yet ranked in North Dakota.
Utah: No list Utah has no state law listing endangered or threatened plants, so we show NatureServe's Utah ranks instead. NatureServe has no Utah rank for it.
Alaska: No list Alaska has no state law listing endangered or threatened plants, so we show NatureServe's Alaska ranks instead. NatureServe has no Alaska rank for it.
California: Not listed Not on California state-listed endangered, threatened and rare plants (14 CCR § 670.2), per CDFW's CNDDB list (July 2026). NatureServe has no California rank for it. ^{CNDDB listed plants (July 2026)}
Mississippi: No list Mississippi has no state law listing endangered or threatened plants, so we show NatureServe's Mississippi ranks instead. NatureServe has no Mississippi rank for it.
Montana: No list Montana has no state law listing endangered or threatened plants, so we show NatureServe's Montana ranks instead. NatureServe has no Montana rank for it.
Nebraska: Not listed Not on Nebraska threatened and endangered species (163 Neb. Admin. Code ch. 4, § 004). NatureServe: SNR, not yet ranked in Nebraska. ^{163 NAC 4-004}
Nevada: Not listed Not on Nevada fully protected plants, critically endangered (NAC 527.010). NatureServe has no Nevada rank for it. ^{NAC 527.010}
Oklahoma: No list Oklahoma has no state law listing endangered or threatened plants, so we show NatureServe's Oklahoma ranks instead. NatureServe: SNR, not yet ranked in Oklahoma.
Oregon: Not listed Not on Oregon endangered and threatened plants (OAR 603-073-0070). NatureServe has no Oregon rank for it. ^{OAR 603-073-0070}
South Dakota: No list South Dakota's endangered and threatened list (ARSD 41:10:02) covers animals only, so we show NatureServe's South Dakota ranks for plants. NatureServe: SNR, not yet ranked in South Dakota.
Washington: No list Washington has no state law listing endangered or threatened plants (the Washington Natural Heritage Program's rare plant list isn't regulatory), so we show NatureServe's Washington ranks instead. NatureServe has no Washington rank for it.
Wyoming: No list Wyoming has no state law listing endangered or threatened plants, so we show NatureServe's Wyoming ranks instead. NatureServe has no Wyoming rank for it.
Rare elsewhere: No other U.S. state ranks it S1, S2, SH or SX.

Checked October 23, 2026. Rankings and lists can change, so follow the links for the latest.

Please leave it where it grows

Please don't pick or dig this flower: Physocarpus opulifolius var. opulifolius is on Delaware's rare plant list (sh, historical); NatureServe ranks it S3 in Georgia. ^{DE rare plants 2024 NatureServe}

Can you eat it?

For peopleNot well documented

None of the sources we checked (NC State Extension (no edibility or poison notes on its page), USDA PLANTS) say whether it's edible or poisonous for people. ^{NC State Extension}

For petsNot well documented

It isn't on the ASPCA plant list, and NC State Extension doesn't flag it for pets.

🌿 Never eat a wild plant unless you're certain of its ID; this isn't medical advice. Worried about a person? Call Poison Control at 1-800-222-1222. Worried about a pet? Call your vet.

Where does it grow?

USDA PLANTS records common ninebark in 35 states plus Washington, D.C.

AKMEVTNHWAIDMTNDMNILWIMINYRIMAORNVWYSDIAINOHPANJCTCAUTCONEMOKYWVVAMDDEAZNMKSARTNNCSCDCOKLAMSALGAHITXFL

recorded by USDA PLANTS on our state lists not recorded

See the full list of states

Alabama, Arkansas, Colorado, Connecticut, Delaware, Florida, Georgia, Illinois, Indiana, Iowa, Kansas, Kentucky, Maine, Maryland, Massachusetts, Michigan, Minnesota, Missouri, Nebraska, New Hampshire, New Jersey, New York, North Carolina, North Dakota, Ohio, Oklahoma, Pennsylvania, Rhode Island, South Carolina, South Dakota, Tennessee, Vermont, Virginia, West Virginia, Wisconsin; District of Columbia.

Michigan counties with USDA records: Alger, Alpena, Antrim, Baraga, Benzie, Berrien, Cass, Charlevoix, Cheboygan, Chippewa, Clare, Crawford, Delta, Dickinson, Emmet, Genesee, Gladwin, Gogebic, Grand Traverse, Gratiot, Hillsdale, Houghton, Ingham, Ionia, Iosco, Iron, Isabella, Kalamazoo, Kalkaska, Kent, Keweenaw, Lake, Lapeer, Leelanau, Lenawee, Livingston, Luce, Mackinac, Macomb, Manistee, Marquette, Mecosta, Menominee, Midland, Missaukee, Monroe, Montcalm, Montmorency, Muskegon, Newaygo, Oakland, Oceana, Ontonagon, Osceola, Otsego, Presque Isle, Schoolcraft, Shiawassee, St. Clair, St. Joseph, Van Buren, Washtenaw, Wayne.

Pennsylvania counties with USDA records: Adams, Allegheny, Armstrong, Beaver, Bedford, Berks, Blair, Bradford, Bucks, Butler, Cambria, Cameron, Centre, Chester, Clarion, Clearfield, Clinton, Columbia, Crawford, Cumberland, Dauphin, Delaware, Elk, Erie, Fayette, Forest, Franklin, Fulton, Greene, Huntingdon, Indiana, Jefferson, Juniata, Lackawanna, Lancaster, Lawrence, Lebanon, Lehigh, Luzerne, Lycoming, McKean, Mercer, Mifflin, Monroe, Montgomery, Montour, Northampton, Northumberland, Perry, Philadelphia, Pike, Potter, Snyder, Somerset, Sullivan, Union, Venango, Warren, Washington, Westmoreland, Wyoming, York.

Ohio counties with USDA records: Adams, Ashland, Ashtabula, Belmont, Butler, Carroll, Champaign, Clark, Clermont, Clinton, Columbiana, Coshocton, Cuyahoga, Defiance, Delaware, Erie, Fairfield, Franklin, Geauga, Greene, Guernsey, Hamilton, Hancock, Harrison, Henry, Highland, Hocking, Holmes, Jackson, Jefferson, Knox, Lake, Lawrence, Licking, Lorain, Lucas, Madison, Mahoning, Medina, Monroe, Montgomery, Muskingum, Noble, Ottawa, Paulding, Perry, Pickaway, Pike, Portage, Preble, Richland, Ross, Scioto, Stark, Summit, Trumbull, Tuscarawas, Vinton, Warren, Washington, Wayne, Wood.

More Michigan flowers

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Sources

USDA, NRCS. PLANTS Database, profile PHOP.
iNaturalist, Physocarpus opulifolius: taxonomy, research-grade observation counts and “Flowering” annotations, retrieved October 23, 2026.
Wikipedia, Physocarpus opulifolius (lead quoted under CC BY-SA 4.0).
Michigan: Michigan endangered and threatened plants (Mich. Admin. Code R 299.1028, eff. March 20, 2023).
Michigan: Michigan prohibited and restricted species (NREPA Part 413 and the 2026 Invasive Species Order), as listed by Michigan's Invasive Species Program.
Pennsylvania: Pennsylvania classified native plants (17 Pa. Code Ch. 45, Subchapter B, as amended 2023).
Pennsylvania: Pennsylvania Noxious Weed List (3 Pa.C.S. § 1519, PA Dept. of Agriculture) (PDA's page spells garlic mustard “Allaria petiolata”; we match it as Alliaria petiolata).
Ohio: Ohio endangered and threatened plants (Ohio Adm. Code 1501:18-1-03, eff. Dec. 26, 2024).
Ohio: Ohio invasive plant species (Ohio Adm. Code 901:5-30-01).
New York: New York protected native plants (6 NYCRR § 193.3).
New York: New York prohibited and regulated invasive species (6 NYCRR Part 575).
Minnesota: Minnesota endangered, threatened and special concern plants (Minn. R. 6134.0300).
Minnesota: Minnesota Noxious Weed List (Minn. Stat. § 18.79; Minnesota Department of Agriculture, updated January 2026).
Wisconsin: Wisconsin endangered and threatened species list (Wis. Admin. Code NR 27.03).
Wisconsin: Wisconsin invasive species rule (Wis. Admin. Code NR 40.04 prohibited, NR 40.05 restricted).
Virginia: Virginia endangered and threatened plant and insect species (2VAC5-320-10).
Virginia: Virginia noxious weeds (2VAC5-317-20, Tier 1, 2 and 3).
Illinois: Illinois List of Endangered and Threatened Flora (17 Ill. Adm. Code 1050), per the Endangered Species Protection Board's 2025 checklist.
Illinois: Illinois Official List of Exotic Weeds (17 Ill. Adm. Code 1100.30, Illinois Exotic Weed Act).
Maryland: Maryland threatened and endangered plants (COMAR 08.03.08.05, .06 and .08).
Maryland: Maryland Prohibited Invasive Plant List (COMAR 15.06.04.06; MDA, updated July 2026).
West Virginia: West Virginia noxious weeds (W. Va. Code R. § 61-14A-5) (the rule abbreviates some names (e.g. “P. cuspidatum”); we expand them to match).
North Carolina: North Carolina Protected Plant Species List (02 NCAC 48F .0301).
North Carolina: North Carolina Noxious Weed List (02 NCAC 48A .1702) (the list names any non-native Lythrum; we apply it to purple loosestrife (Lythrum salicaria), which isn't native).
Maine: Maine Rare Plant List (Maine Natural Areas Program, 2021). E and T are Maine's official endangered and threatened plants (12 M.R.S.); SC and PE are tracking categories.
Maine: Maine Do Not Sell invasive plant list (01-001 C.M.R. ch. 273).
Tennessee: Tennessee endangered plants (Tenn. Comp. R. & Regs. 0400-06-02-.04, Rare Plant Protection and Conservation Act).
Tennessee: Tennessee Pest Plant List (Tenn. Comp. R. & Regs. 0080-06-24-.02).
Vermont: Endangered and Threatened Plants of Vermont (10 V.S.A. chap. 123; list of Feb 10, 2022).
Vermont: Vermont Quarantine List, Regulated Introduced Plant Species Rule (eff. June 16, 2026).
New Hampshire: New Hampshire Official Rare Plants List (Ncr 312, eff. Jan 1, 2020).
New Hampshire: NH Prohibited Invasive Species List (Agr 3800, Table 3800.1).
Indiana: Indiana prohibited invasive terrestrial plants (312 IAC 18-3-25).
Massachusetts: Massachusetts Endangered Species Act list (321 CMR 10.90).
Massachusetts: Massachusetts Prohibited Plant List (MDAR) (Text from MDAR's 2023 scientific-name PDF (mass.gov blocks automated downloads); 2024-2026 additions listed on the mass.gov page: Alnus glutinosa, Pyrus calleryana, Miscanthus sinensis, Aralia elata, Rhodotypos scandens, Symplocos paniculata.).
Kentucky: Kentucky endangered and threatened plant lists (400 KAR 3:040, eff. 2026).
Kentucky: Kentucky noxious weeds and invasive plants on state rights-of-way (KRS 176.051; species list from the Kentucky Transportation Cabinet).
Missouri: Missouri Wildlife Code endangered species (3 CSR 10-4.111), plants.
Missouri: Missouri noxious weed list (2 CSR 70-45.005).
Georgia: Georgia protected plants (Ga. Comp. R. & Regs. 391-4-10-.09; a 2026 update is proposed).
New Jersey: New Jersey Endangered Plant Species List (N.J.A.C. 7:5C-5.1).
New Jersey: New Jersey prohibited invasive plant species (Invasive Species Management Act; propagation banned from Jan 1, 2027, sale from Jan 1, 2030).
Arkansas: Arkansas State Plant Board noxious weeds and prohibited plants (2 CAR § 50-101).
Iowa: Iowa endangered, threatened and special concern plants (Iowa Admin. Code r. 571-77.3).
Iowa: Iowa noxious weeds (Iowa Code § 317.1A).
Rhode Island: Rhode Island Rare Plants 2016 (RI Natural History Survey, from the RI Wildlife Action Plan; informational, Rhode Island has no state plant-protection listing law).
Alabama: Alabama noxious weeds (Ala. Admin. Code r. 80-10-14-.04).
Connecticut: Connecticut Endangered, Threatened and Special Concern Plants (RCSA 26-306; 2015 list).
Connecticut: Connecticut prohibited invasive plants (Conn. Gen. Stat. § 22a-381d).
Delaware: Rare and Uncommon Plants of Delaware (DNREC, 2024; informational, Delaware has no state plant-protection list).
Delaware: Delaware Invasive Plant List (3 Del. Admin. Code § 806-3.0).
Colorado: Colorado noxious weed lists A, B and C (8 CCR 1206-2, eff. May 15, 2025).
South Carolina: South Carolina State Plant Pest List, plants (S.C. Code Regs. 27-135; Clemson Dept. of Plant Industry).
Idaho: Idaho noxious weeds (IDAPA 02.06.09, Section 220).
Kansas: Kansas noxious weeds (K.A.R. 4-8-44, as amended 2026).
North Dakota: North Dakota state noxious weeds (N.D. Admin. Code 7-06-01-02), as listed by the ND Department of Agriculture.
Utah: Utah noxious weed list (Utah Admin. Code R68-9-3).
Alaska: Alaska prohibited and restricted noxious weeds (11 AAC 34.020).
California: California state-listed endangered, threatened and rare plants (14 CCR § 670.2), per CDFW's CNDDB list (July 2026).
California: California noxious weed species (3 CCR § 4500).
Mississippi: Mississippi Noxious Weed List (2 Miss. Code R. 1-3-01-136.01).
Montana: Montana noxious weed list (Admin. R. Mont. 4.5.206–4.5.210).
Nebraska: Nebraska threatened and endangered species (163 Neb. Admin. Code ch. 4, § 004).
Nebraska: Nebraska noxious weeds (25 Neb. Admin. Code ch. 10, § 001.02).
Nevada: Nevada fully protected plants, critically endangered (NAC 527.010).
Nevada: Nevada noxious weeds (NAC 555.010).
Oklahoma: Oklahoma Noxious Weed Law (2 O.S. § 3-220).
Oregon: Oregon endangered and threatened plants (OAR 603-073-0070).
Oregon: Oregon noxious weed quarantine, A and B weeds (OAR 603-052-1200).
South Dakota: South Dakota statewide noxious weeds (ARSD 12:62:03:01.06).
Washington: Washington State noxious weed list (WAC 16-750-005, -011, -015).
Wyoming: Wyoming state designated noxious weeds (W.S. 11-5-102(a)(xi)), as listed by the Wyoming Weed & Pest Council.
USFWS, ECOS species database (ESA listing check), October 23, 2026.
NatureServe Explorer, Physocarpus opulifolius (global and state ranks).
Edibility and toxicity: NC State Extension.
Photo: Senna Bryce Robeson via iNaturalist · CC BY 4.0 · resized.