Enter your ZIP to see whether this is legal to plant in your state, and whether it survives your winter.
Yes, mountain mahogany is consistently rated fire resistant, though that does not mean it is fireproof.
Three extension services agree. Montana State University lists mountain mahogany among fire-resistant species adapted to Montana. Oregon State University includes Cercocarpus species among fire-resistant shrubs and woody vines suited to Willamette Valley growing conditions. Its profile gives the shrub a USDA hardiness range of zones 3 through 9, while the broader reported range is zones 3a through 9b.
The University of Arizona also classifies mountain mahogany as fire resistant in Yavapai County. Its guidance says fire-resistant plants tend to resist ignition when irrigated and maintained, but are not fireproof. That condition belongs to Arizona’s recommendation and explains why the rating should not be read as a promise that the plant cannot burn.
Mountain mahogany is a shrub in the rose family. The agreement across Montana, Oregon, and Arizona provides a clear basis for treating it as fire resistant in a home landscape. In Yavapai County, that favorable rating carries the stated expectation of irrigation and maintenance.
Form
shrub
Rated in
Montana / Northern Rockies; Oregon (Willamette Valley); Yavapai County, Arizona
On this lot
1. Fire evidence and conditions
Fire evidence
Fire-resistant — location does not change the cited classification.
The April 2022 MontGuide explicitly presents fire-resistant species adapted to Montana. FireApproved publishes 92 exact plant records from the source while retaining excluded genus, family, and unresolved rows; the guide itself says not every listed species grows in every part of the state.
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.
Yavapai County (AZ footprint); partial normalized coverage · 2025-03-14
University of Arizona Cooperative Extension authors Bulletin 34 for Yavapai County. FireApproved publishes 198 exact source owners from its resistant and prone tables and keeps the county boundary visible. County publication scope is regional Arizona context, never statewide scope.
2. Why this plant is relevant here
State distribution
Documented in AZ.
Native range
Introduced / established
USDA hardiness
Documented range 3–9.
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.
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.
Fire-resistant Landscape Plants for the Willamette Valley: Mountain Mahogany profile (PDF page 137) [osu-em-9103-profile] (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.
Listed as Mouintain mahogany — Cercocarpus sp.. The bulletin says fire-resistant plants tend to resist ignition when irrigated and maintained, while fire-prone plants may ignite readily and burn intensely.
