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Mountain Ash

Sorbus spp. (accepted: Sorbus) · Rosaceae · all Sorbus records

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: Fire-resistant — location does not change the cited classification.
Fire-performance conditions: No test or rating condition is normalized.
Fire ecology context: No section-reviewed fire-ecology context is normalized.
Placement evidence: 2 source placement records; source schemes remain separate.
Evidence regions: Greece; Oregon (Willamette Valley); Wyoming
Maintenance: No sourced horticultural maintenance assertion is normalized; fire-test conditions do not supply maintenance advice.

Typed publication scope: 2 scopes across 2 cited fire sources

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.
Firewise Landscaping · Official scoped edition
- WY; partial normalized coverage · 2005-04-01
  University of Wyoming Extension published these Firewise examples for its Wyoming rural-living audience and points readers to Firewise Wyoming. FireApproved publishes ten exact source owners while holding broad plant groups. State publication scope is not suitability across every basin.

2. Why this plant is relevant here

State distribution: Documented in OR.
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: Documented range 3–7.

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.

Form: tree
USDA hardiness: 3–7
Grows in: OR
Rated in: Greece; Oregon (Willamette Valley); Wyoming
Family: Rosaceae
Evidence: 3 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.

Fire-resistant Landscape Plants for the Willamette Valley (EM 9103) · EM 9103, February 2015 · as of 2026-08-26

3–7 explicit range · whole zone precision · source stated

Source taxon: Sorbus spp. · exact match.

Source location: Mountain Ash profile (PDF page 176).

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.

Fire-resistant Landscape Plants for the Willamette Valley: Mountain Ash profile (PDF page 176) [osu-em-9103-profile] (with its recommendation)
Κανονισμός Πυροπροστασίας Ακινήτων εντός ή πλησίον δασικώ…: section 5.4.2, Table 2δi [greece-2023-particularly-flammable] (with its avoid 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.

Avoids (1)

Κανονισμός Πυροπροστασίας Ακινήτων εντός ή πλησίον δασικών εκτάσεων — Hellenic Ministry of Environment and Energy · FEK B 3475/2023 · original source Corroboration Regulation

“ΙΔΙΑΙΤΕΡΑ ΕΥΦΛΕΚΤΑ ΕΝΔΗΜΙΚΑ ΦΥΤΑ — Sorbus sp.”

The regulation prints this taxon in its table of particularly flammable endemic trees and shrubs.

Last verified 2026-08-25. JSON (CC BY 4.0)

Profiles: GBIF ·

Sorbus spp. (Mountain Ash). FireApproved. https://fireapproved.com/plants/sorbus/. Last verified 2026-08-25.