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Oregon grape

Mahonia aquifolium · Berberidaceae · all Mahonia records · also called Holly-leaved barberry

Your local evidence lens

Separate evidence questions, never one approval badge

Set a ZIP to compare this record with state distribution, native range, USDA hardiness, and invasive records.

A genus split is not a placement verdict. Set a ZIP to read the local documented split.

1. Fire evidence and conditions

Fire evidence: Mixed evidence — location does not change the cited classification.
Fire-performance conditions: 2 conditions stated in cited fire-evidence rows.
Fire ecology context: No section-reviewed fire-ecology context is normalized.
Placement evidence: 8 source placement records; source schemes remain separate.
Evidence regions: Ashland, Oregon; British Columbia; Marin County, California; Michigan / Great Lakes; Nevada / Great Basin; OR/WA/ID; Ohio / Midwest; Oregon; Oregon (Willamette Valley); Pacific Northwest (Oregon / Washington / Idaho); SoCal; Virginia / Mid-Atlantic; eastern US; southern Idaho / Intermountain
Maintenance: No sourced horticultural maintenance assertion is normalized; fire-test conditions do not supply maintenance advice.

Typed publication scope: 9 scopes across 9 cited fire sources

Prohibited Flammable Plants (Ashland Municipal Code 9.04) · Official scoped edition
- City of Ashland (OR footprint); partial normalized coverage · 2026-08-26
  This is a City of Ashland adoption fact, not statewide Oregon guidance or an experimental flammability result. FireApproved publishes 24 taxonomy-safe owners as city-level regulatory context. It applies to new planting and propagation within 30 feet of structures, including structures on adjacent lots; it is not projected as a blanket removal order for every established listed plant.
Fire-Resistant Plants Common to Marin County · Official scoped edition
- Marin County (CA footprint); partial normalized coverage · 2019-01-01
  The publication is explicitly limited to plants common to Marin County. FireApproved publishes 104 exact owners as Marin regional context while retaining its placement, spacing, irrigation, and maintenance boundary. It is not statewide California guidance or parcel suitability.
Fire Resistance of Plants Master Database · Official scoped edition
- Southern Idaho (ID footprint); partial normalized coverage · 2013-11-08
  The official database labels itself "For Southern Idaho" and describes Idaho residents at the urban-rangeland interface. FireApproved publishes 419 existing plant owners that cite its scored rows. This bounded Southern Idaho scope is regional context, not statewide coverage or a conclusion that the score transfers unchanged to every Idaho site.
Wildfire-resistant Landscape Plants for Michigan (Extension Bulletin E2948) · Official scoped edition
- MI; partial normalized coverage · 2007-01-01
  Michigan State University Extension Bulletin E2948 is explicitly a list of wildfire-resistant landscape plants for Michigan and includes a Michigan-native field. FireApproved publishes 221 exact GBIF owners from 226 represented source rows and holds 15 complex or non-exact rows. This dated publication scope is not a current site-suitability determination.
Firewise Landscaping (OSU Extension Bulletin 921) · Official scoped edition
- OH; partial normalized coverage · 2006-03-01
  Ohio State University Extension Bulletin 921 is an Ohio publication that describes Ohio fire seasons and landscape conditions and labels nativity to Ohio. FireApproved publishes 352 exact source-owning plant records from its eight rated tables. This historical publication scope does not assert current extension endorsement or that a listed plant suits every Ohio site.
Fire-resistant Landscape Plants for the Willamette Valley (EM 9103) · Official scoped edition
- Willamette Valley (OR footprint); partial normalized coverage · 2015-02-01
  OSU Extension says EM 9103 highlights fire-resistant plants that thrive under Willamette Valley growing conditions. FireApproved publishes 172 exact owners only as valley context. The guide shares the PNW 590 lineage and is not a second independent vote or statewide site clearance.
Fire-Resistant Plants for Home Landscapes (PNW 590) · Official scoped edition
- ID, OR, WA; partial normalized coverage · 2023-10-01
  The October 2023 joint Pacific Northwest Extension publication explicitly names Oregon, Washington, and Idaho and publishes more than 150 plant profiles. FireApproved has normalized 155 exact plant records from the source; publication scope does not assert that every listed plant suits every site within the three states.
A Compilation of Good Plant Choices for Nevada's High Fire Hazard Areas (SP-05-16) · Official scoped edition
- NV; partial normalized coverage · 2005-01-01
  University of Nevada Cooperative Extension compiled plants suited to Nevada climate zones and reported favorably by at least two upstream firewise lists. FireApproved publishes 126 exact source owners at Nevada publication scope. The source explicitly makes no independent flammability determination, so these rows remain corroborative.
Virginia Firescapes — Firewise Landscaping for Woodland Homes (430-300) · Official scoped edition
- VA; partial normalized coverage · 2009-04-15
  Virginia Cooperative Extension's publication opens with Virginia wildfire conditions, identifies its Virginia Firewise Landscaping Task Force, and labels plants native to Virginia. FireApproved publishes 306 exact source owners. Publication scope does not establish parcel suitability or current endorsement of this archived 2009 list.

2. Why this plant is relevant here

State distribution: Documented in CA, DC, GA, ID, KY, MI, MT, NJ, NY, OH, OR, WA.
Native range: No current cited or legacy state native range is normalized.
Introduced / established: No introduced or established row is normalized; that does not prove native status.
USDA hardiness: 3 applicable cited hardiness statements overlap but have different boundaries; compare each complete source row.

3. Legal, ecological, and broader status

Legal-list status: Set a location for an exact legal-list result; source silence is not clearance.
Seed-list status: Set a location to compare the separate state noxious-weed seed layer.
Reported invasive here: No ecological invasive report is normalized; that does not prove noninvasiveness.
Broader regional context: Aggregate AK, HI, and L48 evidence is shown only as regional context, never as an exact-state finding.
Federal context: Federal designations remain separate from state legal-list results.

How to read this page

The status above is computed from the cited rows below: independent recommendations can support a fire-resistant result, an avoid row can produce keep-away, and disagreement stays visible as conflict. Placement notes preserve each source’s own scheme rather than translating unlike rules into one scale. This is evidence about a plant, not permission to plant it in every part of the defensible space; Zone 0 remains noncombustible.

Oregon grape (Mahonia aquifolium) — Photo: (c) Gavin Slater, some rights reserved (CC BY) (CC BY), via iNaturalist. Species-typical, not necessarily this cultivar.

Form: shrub
USDA hardiness: Applicable source statements overlap but have different boundaries; compare each source
Mature height: ~8 ft
Water need: low
Grows in: CA, DC, GA, ID, KY, MI, MT, NJ +4
Rated in: Ashland, Oregon; British Columbia; Marin County, California; Michigan / Great Lakes +10
Family: Berberidaceae
Evidence: 14 cited sources

Plant hardiness evidence

These values describe the plant source. Your ZIP zone comes from the separate 2023 USDA Plant Hardiness Zone Map. Whole-zone values stay whole-zone, and a single unresolved value is not treated as a tolerance range. Different source boundaries stay separate: overlapping statements are compared independently, while only ranges with no shared zone are called a conflict.

Eastern United States Fire Performance Plant Selector · record mahonia-aquifolium · 2016-wayback · as of 2026-08-26

Source prints 5 · single-value meaning unresolved · whole zone precision · source stated

Source taxon: Mahonia aquifolium · exact match.

Source location: Cold Hardiness Zone field in the recovered selector record.

Not used for comparison: The recovered selector prints one Cold Hardiness Zone value but does not define it as a minimum threshold or a one-zone range.
Wildfire-resistant Landscape Plants for Michigan (Extension Bulletin E2948) · record shrub:Mahonia aquifolium · New, January 2007 · as of 2026-08-26

5–8 explicit range · whole zone precision · source stated

Source taxon: Mahonia aquifolium · exact match.

Source location: Table 1, shrub row.
Fire-resistant Landscape Plants for the Willamette Valley (EM 9103) · EM 9103, February 2015 · as of 2026-08-26

5–8 explicit range · whole zone precision · source stated

Source taxon: Berberis (Mahonia) aquifolium · exact match.

Source location: Oregon Grape profile (PDF page 142).
USDA PLANTS Database — Plant Characteristics · record MAAQ2 · PLANTS Help Document 2022; characteristics cache retrieved 2026-08-23 · as of 2026-08-26

Minimum 2b · no upper limit documented · half zone precision · derived containing band

Exact source measurement: -43°F; mapped only to its containing half-zone.

Source taxon: Mahonia aquifolium · source identifier match.

Source location: PlantCharacteristics record 72329, Temperature, Minimum (°F).

Conditions in the fire evidence

These describe tested or rated plant material. They are not horticultural maintenance instructions.

green: Fire-Resistant Plants for Oregon Home Landscapes evidence row
irrigated: Fire-Resistant Plants Common to Marin County evidence row

Where its sources say to plant it

Placement rules below use each source's own distances or named zones, tied to its rating. They are not interchangeable with the directory's current Zone 0 guidance.

Eastern United States Fire Performance Plant Selector: Landscape Zone 2 — 5–10 ft from the structure; maintained lawn or fuel breaks, with easily ignited evergreens avoided [Fire Performance Plant Selector landscape zone] (mid-scale rating)
Fire Resistance of Plants Master Database: plantable at 70' from home [Idaho minimum planting distance] (mid-scale rating)
Firewise Landscaping: do not plant within 5 ft of structures (keep out of Zone 1) [OSU B921 source-category siting] (with its avoid rating)
Prohibited Flammable Plants: new planting or propagation restricted within 30 ft of any structure [Ashland Municipal Code setback] (with its avoid rating)
FireSmart BC Plant Program: suitable for HIZ extended zone and beyond [FireSmart BC Home Ignition Zone] (with its recommendation)
Fire-Resistant Plants for Oregon Home Landscapes: Oregon [osu-frn6-oregon-regions] (with its recommendation)
Fire-resistant Landscape Plants for the Willamette Valley: Oregon Grape profile (PDF page 142) [osu-em-9103-profile] (with its recommendation)
Fire-resistant plant profile galleries: Oregon grape — Berberis aquifolium [osu-2023-broadleaf-evergreens-gallery] (with its recommendation)

The evidence

Grouped by what each source concluded. Primary evidence rated the plant itself (a lab, field program, or original curation); corroboration compiled or republished another source's rating and resolves to its root lineage.

Avoids (3)

Firewise Landscaping (OSU Extension Bulletin 921) — Ohio State University Extension (Sydnor, Steward, Kloss / Ohio DNR Division of Forestry) · 2006 · original source Primary evidence Expert-curated lineage: ufifas-srs-tree

“H flammability”

Susceptible to winter desiccation; urban adaptive.
Virginia Firescapes — Firewise Landscaping for Woodland Homes (430-300) — Virginia Cooperative Extension / Virginia Tech (Appleton, Frenzel, Hillegass, Lyons, Steward — Virginia Firewise Landscaping Task Force) · 2009 · original source Primary evidence Expert-curated lineage: ufifas-srs-tree

“H flammability”

Susceptible to winter dessication.
Prohibited Flammable Plants (Ashland Municipal Code 9.04) — City of Ashland, Oregon (Fire & Rescue / Weed Abatement) · 2025 · original source Primary evidence Regulation lineage: pnw590-tree

“prohibited flammable plant” · original source

The City of Ashland restricts new planting or propagation within 30 ft of any structure, including structures on adjacent lots (AMC 9.04). Dwarf or prostrate varieties require Fire and Rescue approval, placement beyond 5 ft, and ordinance-compliant tree or shrub spacing.

Mid-scale / conditional (2)

Eastern United States Fire Performance Plant Selector — USDA Forest Service Northeastern Area S&PF + state Firewise programs (WV, OH, PA, DE, DC, MD, NJ) · 2016-wayback · original source Primary evidence Keyed curation lineage: ufifas-srs-tree

“MODERATELY Firewise (2)”

Glossy green foliage appearring to be a holly except with compound leaves. Bright yellow terminal floqwer clusters in early spring with bright blue fruit in summer.
Fire Resistance of Plants Master Database — Idaho Firewise (BLM + College of Western Idaho + Idaho Botanical Garden) · original source Primary evidence Field program lineage: idaho-tree

“fire-resistance score 4 of 10” · score 4 (idaho-0-10)

Fire-resistant shrubs instead

Northern elderberry
Sambucus pubens

Snowberry
Symphoricarpos albus Red elderberry
Sambucus racemosa

Red-osier dogwood
Cornus sericea

'Gro-Low' fragrant sumac
Rhus aromatica

Black chokeberry
Aronia melanocarpa

Fire-resistant shrubs listed above

Last verified 2026-08-23. JSON (CC BY 4.0)

Profiles: USDA PLANTS · GBIF · iNaturalist · Wikidata · ITIS

Mahonia aquifolium (Oregon grape, Holly-leaved barberry). FireApproved. https://fireapproved.com/plants/mahonia-aquifolium/. Last verified 2026-08-23.