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Black walnut

Juglans nigra · 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: 6 source placement records; source schemes remain separate.
Evidence regions: Arkansas; British Columbia; Georgetown, Texas; Maryland, New Jersey, and West Virginia; Ohio / Midwest; Tennessee; Virginia / Mid-Atlantic; Yavapai County, Arizona; eastern US; southern Idaho / Intermountain
Maintenance: No sourced horticultural maintenance assertion is normalized; fire-test conditions do not supply maintenance advice.

Typed publication scope: 9 scopes across 7 cited fire sources

Fire Resistance of Plants Master Database · Official scoped edition
- Southern Idaho (ID footprint); partial normalized coverage · 2013-11-08
  The official database labels itself "For Southern Idaho" and describes Idaho residents at the urban-rangeland interface. FireApproved publishes 419 existing plant owners that cite its scored rows. This bounded Southern Idaho scope is regional context, not statewide coverage or a conclusion that the score transfers unchanged to every Idaho site.
Firewise Landscaping Plants (Maryland, New Jersey, and West Virginia editions) · Official scoped edition
- MD; partial normalized coverage · 2015-01-08
  Maryland Forest Service says the list contains plants that can be grown in Maryland and identifies Maryland natives. FireApproved publishes 169 exact source owners from the 180 printed rows; an unrepresentable form and duplicate-owner rows are not broadened. The list calls itself non-comprehensive and does not establish suitability for every Maryland site.
- NJ; partial normalized coverage
  New Jersey DEP publishes a state edition saying the listed plants can be grown in New Jersey and are relatively resistant to fire. Its same 180 printed taxon occurrences map to the 169 conservative owners already normalized for the template family. The list is non-comprehensive and does not establish suitability for every New Jersey site or override the Pinelands Commission's separate placement and fuel-break rules.
- WV; partial normalized coverage · 2026-08-26
  West Virginia Division of Forestry publishes a state edition saying the listed plants can be grown in West Virginia and are relatively resistant to fire. Its same 180 printed taxon occurrences map to the 169 conservative owners already normalized for the template family. The list is non-comprehensive and provides no comparative or site-specific rating.
Firewise Landscaping (OSU Extension Bulletin 921) · Official scoped edition
- OH; partial normalized coverage · 2006-03-01
  Ohio State University Extension Bulletin 921 is an Ohio publication that describes Ohio fire seasons and landscape conditions and labels nativity to Ohio. FireApproved publishes 352 exact source-owning plant records from its eight rated tables. This historical publication scope does not assert current extension endorsement or that a listed plant suits every Ohio site.
Firewise Plant Guide · Official scoped edition
- Sun City Texas, Georgetown (TX footprint); partial normalized coverage · 2015-01-14
  The guide is authored for the Sun City Texas community in Georgetown. FireApproved publishes 142 exact owners only as community-level context. It is an archived HOA exhibit with unknown rating lineage, not a current statewide Texas source or an independent Tier 1 determination.
Landscaping Guidelines to Protect Your Home from Wildfire (SP685) · Official scoped edition
- TN; partial normalized coverage · 2006-10-24
  University of Tennessee Extension SP685 is Tennessee landscape guidance and publishes 78 represented plant owners. Most table rows are a carrier of Virginia Firescapes rather than an independent rating; Tennessee source scope does not change that lineage or establish site suitability.
Virginia Firescapes — Firewise Landscaping for Woodland Homes (430-300) · Official scoped edition
- VA; partial normalized coverage · 2009-04-15
  Virginia Cooperative Extension's publication opens with Virginia wildfire conditions, identifies its Virginia Firewise Landscaping Task Force, and labels plants native to Virginia. FireApproved publishes 306 exact source owners. Publication scope does not establish parcel suitability or current endorsement of this archived 2009 list.
Fire-Resistant and Fire-Prone Plants Common to Yavapai County (Bulletin 34) · Official scoped edition
- 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 AL, AR, CO, CT, DC, DE, FL, GA, IA, IL, IN, KS, KY, LA, MA, MD, ME, MI, MN, MO, MS, NC, ND, NE, NH, NJ, NM, NY, OH, OK, PA, RI, SC, SD, TN, TX, UT, VA, WI, WV.
Native range: Current cited native range in AL, AR, CT, DC, DE, FL, GA, IA, IL, IN, KS, KY, LA, MA, MD, MI, MN, MO, MS, NC, NE, NJ, NY, OH, OK, PA, RI, SC, SD, TN, TX, VA, WI, WV.
Introduced / established: 2 sourced range or established records; set a location to match them. This is not an invasive warning.
USDA hardiness: Documented minimum 4a; 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: 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.

Black walnut (Juglans nigra) — Photo: (c) Sandy Wolkenberg, some rights reserved (CC BY) (CC BY), via iNaturalist. Species-typical, not necessarily this cultivar.

Form: tree
USDA hardiness: Minimum 4a; upper limit not documented
Mature height: ~50 ft
Light: Full sun
Water need: high
Current cited native range: AL, AR, CT, DC, DE, FL, GA, IA, IL, IN, KS, KY, LA, MA, MD, MI, MN, MO, MS, NC, NE, NJ, NY, OH, OK, PA, RI, SC, SD, TN, TX, VA, WI, WV
Grows in: AL, AR, CO, CT, DC, DE, FL, GA +32
Rated in: Arkansas; British Columbia; Georgetown, Texas; Maryland, New Jersey, and West Virginia +6
Family: Juglandaceae
Evidence: 10 cited sources

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.

Current native

34

exact source areas

Current introduced

2

exact source areas

Qualified

0

doubtful or extinct source rows

34 native source areas · World Checklist of Vascular Plants, version 16 v16, as of 2026-06-04

Alabama (AL)
Arkansas (AR)
Connecticut (CT)
District of Columbia (DC)
Delaware (DE)
Florida (FL)
Georgia (GA)
Iowa (IA)
Illinois (IL)
Indiana (IN)
Kansas (KS)
Kentucky (KY)
Louisiana (LA)
Massachusetts (MA)
Maryland (MD)
Michigan (MI)
Minnesota (MN)
Missouri (MO)
Mississippi (MS)
North Carolina (NC)
Nebraska (NE)
New Jersey (NJ)
New York (NY)
Ohio (OH)
Oklahoma (OK)
Pennsylvania (PA)
Rhode I. (RI)
South Carolina (SC)
South Dakota (SD)
Tennessee (TN)
Texas (TX)
Virginia (VA)
Wisconsin (WI)
West Virginia (WV)

2 introduced source areas · World Checklist of Vascular Plants, version 16 v16, as of 2026-06-04

New Mexico (NM)
Vermont (VT)

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.

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

Source prints 5 · single-value meaning unresolved · whole zone precision · source stated

Source taxon: Juglans nigra · 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 JUNI · PLANTS Help Document 2022; characteristics cache retrieved 2026-08-23 · as of 2026-08-26

Minimum 4a · no upper limit documented · half zone precision · derived containing band

Exact source measurement: -28°F; mapped only to its containing half-zone.

Source taxon: Juglans nigra · source identifier match.

Source location: PlantCharacteristics record 70684, 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)
Fire Resistance of Plants Master Database: plantable at 70' from home [Idaho minimum planting distance] (mid-scale rating)
FireSmart BC Plant Program: suitable for HIZ extended zone and beyond [FireSmart BC Home Ignition Zone] (with its recommendation)
Firewise Plant Guide: Hardwood Trees [Sun City plant-table sections] (with its recommendation)
Firewise Landscaping Plants: Deciduous Trees [Maryland Firewise plant-form tables] (with its recommendation)
FireWise Plants offer colorful choices for Fire Safe Gardens: Scientific name / Common name / Comments table [arkansas-firewise-table] (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)

Fire Resistance of Plants Master Database — Idaho Firewise (BLM + College of Western Idaho + Idaho Botanical Garden) · original source Primary evidence Field program lineage: idaho-tree

“fire-resistance score 4 of 10” · score 4 (idaho-0-10)

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

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

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