Enter your ZIP to see whether this is legal to plant in your state, and whether it survives your winter.
Yes, prostrate ceanothus is consistently listed as fire resistant, though the classification rests on limited primary evidence.
Agreement spans six recommendations, including the joint extension service of Oregon State, Washington State, and the University of Idaho, which lists the plant as fire resistant. Anaheim Fire & Rescue includes it among acceptable fire-resistive species. FireSmart BC also approves it as fire resistant, but flags the plant as needing more research. These are expert-curated or compiled recommendations rather than results from a common numerical flammability test.
Oregon State’s extension service repeatedly recommends prostrate ceanothus, also called Mahala mat or squaw carpet, as a fire-resistant groundcover. Its statewide guidance places the species among groundcovers 18 inches and lower for Central, Eastern, and Southern Oregon. That recommendation assumes most listed plants receive some irrigation during Oregon’s dry summers and remain healthy through maintenance. A separate Willamette Valley profile recommends it for that region’s growing conditions and gives zones 5 through 8, while the broader regional extension guide gives USDA zones 4a through 8b.
Prostrate ceanothus is a low-water groundcover in the buckthorn family, reaching about half a foot at maturity and native to the southwestern and northwestern United States. The agreement across regional extension services and a fire department supports calling it fire resistant, but FireSmart BC’s research flag is a useful limit: this is a consistent planting recommendation, not a guarantee that the plant cannot burn.
Form
groundcover
Mature height
~0.5 ft
Water need
low
Rated in
British Columbia; California; OR/WA/ID; Oregon +4
On this lot
1. Fire evidence and conditions
Fire evidence
Fire-resistant — location does not change the cited classification.
The UC Forest Products Laboratory says the guide covers properties of common California landscaping plants and was prepared for California fire agencies. FireApproved publishes 130 exact owners at historical California publication scope. The report is a 1997 compilation, not a current endorsement, site rating, or independent test of every row.
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.
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.
2. Why this plant is relevant here
State distribution
Documented in CA, ID, NV, OR, WA.
Native range
Current cited native range in CA, ID, NV, OR, WA.
Introduced / established
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
Seed-list status
Reported invasive here
Broader regional context
Federal context
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.
Native and introduced range evidence
These are exact U.S. botanical-area records from the cited range source. Native and
introduced describe biogeographic relationship, not fire performance or planting approval.
Doubtful and extinct rows stay visible but do not count as current presence.
The lossless worldwide derivative is retained once in the research corpus; object pages repeat only exact U.S. areas needed by the local lens. The JSON twin carries the same page assertions.
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.
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.
Low-volume and slow-burning vegetation for planting on cl…: Table 3: Fair performance [nord-green-brushland-clearing-performance] (mid-scale rating)
Fire-Resistant Plants for Oregon Home Landscapes: Central, Eastern, and Southern Oregon [osu-frn6-oregon-regions] (with its recommendation)
Fire-resistant Landscape Plants for the Willamette Valley: Mahala Mat profile (PDF page 17) [osu-em-9103-profile] (with its recommendation)
Fire-resistant plant profile galleries: Mahala mat — Ceanothus prostratus [osu-2023-groundcovers-gallery] (with its recommendation)
Defensible Space Landscaping in the Urban/Wildland Interf…: Chapter 4, Landscape Vegetation Database [ucfpl-1997] (mid-scale rating)
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.
“Fire-Resistant Plant Materials for Oregon”
· condition: green
Ceanothus prostratus (Squaw carpet) is listed under “Groundcovers 18 inches and lower” for Central, Eastern, and Southern Oregon. The guide says most listed plants require some irrigation during Oregon's dry summer months and must be maintained in a healthy condition.
