Documented minimum 3b; no upper limit is documented.
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.
Source prints 4 · single-value meaning unresolved · whole zone precision · source stated
Source taxon: Malus x zumi var. calocarpa · 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.
Minimum 3b · no upper limit documented · half zone precision · derived containing band
Exact source measurement: -33°F; mapped only to its containing half-zone.
Source taxon: Malus x zumi var. calocarpa · source identifier match.
Source location: PlantCharacteristics record 90131, Temperature, Minimum (°F).
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 3 — 10–30 ft from the structure; thin vegetation, remove debris, and minimize plant massing [Fire Performance Plant Selector landscape zone] (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.