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English walnut

Juglans regia · Juglandaceae · all Juglans 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: 1 source placement record; source schemes remain separate.
Evidence regions: Global; New Zealand; eastern US
Maintenance: No sourced horticultural maintenance assertion is normalized; fire-test conditions do not supply maintenance advice.

2. Why this plant is relevant here

State distribution: Documented in CA, DC, DE, ID, MD, MI, NJ, NY, OH, PA, WA, WV.
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 minimum 6a; no upper limit is documented.

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: 1 ecological invasive report; set a location to distinguish exact from regional context.
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.

English walnut (Juglans regia) — Photo: (c) Gianni Del Bufalo bygdb, some rights reserved (CC BY) (CC BY), via iNaturalist. Species-typical, not necessarily this cultivar.

Form: tree
USDA hardiness: Minimum 6a; upper limit not documented
Mature height: ~35 ft
Light: Full sun
Water need: high
Grows in: CA, DC, DE, ID, MD, MI, NJ, NY +4
Rated in: Global; New Zealand; eastern US
Family: Juglandaceae
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.

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

Source prints 6 · single-value meaning unresolved · whole zone precision · source stated

Source taxon: Juglans regia · 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.
USDA PLANTS Database — Plant Characteristics · record JURE80 · PLANTS Help Document 2022; characteristics cache retrieved 2026-08-23 · as of 2026-08-26

Minimum 6a · no upper limit documented · half zone precision · derived containing band

Exact source measurement: -8°F; mapped only to its containing half-zone.

Source taxon: Juglans regia · source identifier match.

Source location: PlantCharacteristics record 70687, 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] (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.

Mid-scale / conditional (1)

Low Flammability Plants directory — Fire and Emergency New Zealand (plant flammability testing at Lincoln University) · 2026 · original source Primary evidence Lab-tested lineage: lincoln-nz-tree

“Moderate flammability”

Moderate flammability classification.

Listed without a rating (1)

FLAMITS: FLAMmability plant traiTS database — Dryad / Global Ecology and Biogeography · Dryad version 9 · original source Corroboration Trait database lineage: meta-aggregator

“calorific value (kcal/kg): 4781.69” · score 4781.69 (FLAMITS — calorific value (kcal/kg))

FLAMITS record 3920; Combustibility measurement; plant part twigs; fuel live; predrying yes; device calorimeter; site Gillon1997-1; sampling june to september. Primary study Gillon1997: Gillon, D., Hernando, C., Valette, J.-C., & Joffre, R. (1997). Fast estimation of the calorific values of forest fuels by near infrared-reflectance spectroscopy. Canadian Journal of Forest Research, 27, 760-765.

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

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

Juglans regia (English walnut). FireApproved. https://fireapproved.com/plants/juglans-regia/. Last verified 2026-08-23.