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Thornless honeylocust

Gleditsia triacanthos · Fabaceae

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: 1 condition stated in cited fire-evidence rows.
Fire ecology context: No section-reviewed fire-ecology context is normalized.
Placement evidence: 8 source placement records; source schemes remain separate.
Evidence regions: Arizona above 3,000 feet / interior Southwest; Arkansas; Black Hills, South Dakota; British Columbia; Catalonia, Spain; Louisiana; Michigan / Great Lakes; Nevada / Great Basin; OR/WA/ID; Ohio / Midwest; Oregon; Tasmania, Australia; Virginia / Mid-Atlantic; Yavapai County, Arizona; eastern US; eastern WA; southern Idaho / Intermountain
Maintenance: No sourced horticultural maintenance assertion is normalized; fire-test conditions do not supply maintenance advice.

Typed publication scope: 11 scopes across 11 cited fire sources

Firewise Plant Material for the Black Hills · Official scoped edition
- Black Hills (SD footprint); partial normalized coverage
  The page explicitly limits itself to the Black Hills, and NFPA Firewise's archived 2006 plant-list index files it under South Dakota. FireApproved publishes 47 exact genus or species owners from 48 printed rows. This is bounded Black Hills context, not statewide South Dakota coverage or a finding that a plant suits a particular site.
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 (Hammond Research Station) · Official scoped edition
- LA; partial normalized coverage · 2008-12-02
  LSU AgCenter calls these 31 ornamentals commonly used in Louisiana and recommended for Louisiana firewise landscaping efforts. FireApproved publishes 31 exact source owners, mostly at the source's genus grain. Undocumented curation remains corroborative and is not site suitability.
Wildfire-resistant Landscape Plants for Michigan (Extension Bulletin E2948) · Official scoped edition
- MI; partial normalized coverage · 2007-01-01
  Michigan State University Extension Bulletin E2948 is explicitly a list of wildfire-resistant landscape plants for Michigan and includes a Michigan-native field. FireApproved publishes 221 exact GBIF owners from 226 represented source rows and holds 15 complex or non-exact rows. This dated publication scope is not a current site-suitability determination.
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.
Fire-Resistant Plants for Home Landscapes (PNW 590) · Official scoped edition
- ID, OR, WA; partial normalized coverage · 2023-10-01
  The October 2023 joint Pacific Northwest Extension publication explicitly names Oregon, Washington, and Idaho and publishes more than 150 plant profiles. FireApproved has normalized 155 exact plant records from the source; publication scope does not assert that every listed plant suits every site within the three states.
FIREWISE Plant Materials for 3,000 ft. and Higher Elevations (AZ1289) · Official scoped edition
- Arizona at or above 3,000 feet (AZ footprint); partial normalized coverage · 2011-12-01
  AZ1289 is explicitly limited to Arizona elevations of 3,000 feet and higher. FireApproved publishes 69 exact owners as regional Arizona context, retaining every water and elevation condition. It is never promoted to statewide low-desert guidance or an independent Tier 1 vote.
A Compilation of Good Plant Choices for Nevada's High Fire Hazard Areas (SP-05-16) · Official scoped edition
- NV; partial normalized coverage · 2005-01-01
  University of Nevada Cooperative Extension compiled plants suited to Nevada climate zones and reported favorably by at least two upstream firewise lists. FireApproved publishes 126 exact source owners at Nevada publication scope. The source explicitly makes no independent flammability determination, so these rows remain corroborative.
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 Plants for Eastern Washington · Official scoped edition
- Eastern Washington (WA footprint); partial normalized coverage
  Washington DNR publishes the guide for Eastern Washington and says it compiles plants from other Firewise documents that are likely to thrive there. FireApproved publishes 46 exact owners only as eastern Washington context. The rows are corroborative, not empirical or statewide.
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, AZ, CA, CO, CT, DC, DE, FL, GA, IA, ID, IL, IN, KS, KY, LA, MA, MD, ME, MI, MN, MO, MS, MT, NC, ND, NE, NH, NJ, NM, NV, NY, OH, OK, OR, PA, RI, SC, SD, TN, TX, UT, VA, VT, WA, WI, WV, WY.
Native range: Current cited native range in AL, AR, CT, DC, DE, FL, GA, IA, IL, IN, KS, KY, LA, MA, MD, ME, MI, MN, MO, MS, NC, ND, NE, NH, NJ, NV, NY, OH, OK, PA, RI, SC, SD, TN, TX, UT, VA, VT, WI, WV, WY.
Introduced / established: 8 sourced range or established records; set a location to match them. This is not an invasive warning.
USDA hardiness: 3 applicable cited hardiness statements overlap but have different boundaries; compare each complete source row.

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.

Thornless honeylocust (Gleditsia triacanthos) — Photo: (c) Lisa Bennett, some rights reserved (CC BY) (CC BY), via iNaturalist. Species-typical, not necessarily this cultivar.

Form: tree
USDA hardiness: Applicable source statements overlap but have different boundaries; compare each source
Mature height: ~70 ft
Water need: low
Current cited native range: AL, AR, CT, DC, DE, FL, GA, IA, IL, IN, KS, KY, LA, MA, MD, ME, MI, MN, MO, MS, NC, ND, NE, NH, NJ, NV, NY, OH, OK, PA, RI, SC, SD, TN, TX, UT, VA, VT, WI, WV, WY
Grows in: AL, AR, AZ, CA, CO, CT, DC, DE +41
Rated in: Arizona above 3,000 feet / interior Southwest; Arkansas; Black Hills, South Dakota; British Columbia +13
Family: Fabaceae
Evidence: 17 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

41

exact source areas

Current introduced

8

exact source areas

Qualified

0

doubtful or extinct source rows

41 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)
Maine (ME)
Michigan (MI)
Minnesota (MN)
Missouri (MO)
Mississippi (MS)
North Carolina (NC)
North Dakota (ND)
Nebraska (NE)
New Hampshire (NH)
New Jersey (NJ)
Nevada (NV)
New York (NY)
Ohio (OH)
Oklahoma (OK)
Pennsylvania (PA)
Rhode I. (RI)
South Carolina (SC)
South Dakota (SD)
Tennessee (TN)
Texas (TX)
Utah (UT)
Virginia (VA)
Vermont (VT)
Wisconsin (WI)
West Virginia (WV)
Wyoming (WY)

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

Alaska (AK)
Arizona (AZ)
California (CA)
Colorado (CO)
Idaho (ID)
Montana (MT)
New Mexico (NM)
Washington (WA)

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 gleditsia-triacanthos · 2016-wayback · as of 2026-08-26

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

Source taxon: Gleditsia triacanthos · 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.
Wildfire-resistant Landscape Plants for Michigan (Extension Bulletin E2948) · record tree:Gleditsia triacanthos · New, January 2007 · as of 2026-08-26

4–9 explicit range · whole zone precision · source stated

Source taxon: Gleditsia triacanthos · exact match.

Source location: Table 1, tree row.
Fire-Resistant Plants for Home Landscapes (PNW 590) · 2023-10 · as of 2026-08-26

3–9 explicit range · whole zone precision · source stated

Source taxon: Gleditsia triacanthos · exact match.

Source location: Plant profile USDA hardiness zones field.
USDA PLANTS Database — Plant Characteristics · record GLTR · 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: -30°F; mapped only to its containing half-zone.

Source taxon: Gleditsia triacanthos · source identifier match.

Source location: PlantCharacteristics record 79383, Temperature, Minimum (°F).

Conditions in the fire evidence

These describe tested or rated plant material. They are not horticultural maintenance instructions.

green: Fire-Resistant Plants for Oregon Home Landscapes evidence row

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 Resisting Garden Plants for the Urban Fringe and Rur…: remove from the Building Protection Zone; avoid in the Fuel Modified Zone [Texas Building Protection Zone] (with its avoid rating)
FireSmart BC Plant Program: suitable for HIZ extended zone and beyond [FireSmart BC Home Ignition Zone] (with its recommendation)
Fire Resistance of Plants Master Database: plantable at 70' from home [Idaho minimum planting distance] (mid-scale rating)
Fire-Resistant Plants for Oregon Home Landscapes: Oregon [osu-frn6-oregon-regions] (with its recommendation)
Guía de pirojardinería: not suitable inside the 25-metre maximum-risk zone [girona-2020-iuf-25m-suitability] (with its avoid rating)
Firewise Plant Material for the Black Hills: Large shrubs & trees [black-hills-plant-form-table] (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.

Avoids (2)

Fire Resisting Garden Plants for the Urban Fringe and Rural Areas — Tasmania Fire Service (Chladil & Sheridan; photographs Royal Tasmanian Botanical Gardens) · 2017 · original source Primary evidence Expert-curated lineage: utas-tree

“High Flammability”
Guía de pirojardinería — guía práctica de jardinería adaptada a la prevención de incendios forestales — Diputació de Girona and Bombers de la Generalitat de Catalunya · 2020 Spanish edition · original source Primary evidence Expert-curated lineage: elvira-hernando-1989 + cooperem-tree

“DESACONSEJADA”

Gleditsia triacanthos is rated “DESACONSEJADA” by the guide's qualitative IUF garden-suitability method. The method assumes species-specific care and integrates fire evidence with fuel structure, maintenance, origin, invasiveness, and expert fire-service experience.

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

Gleditsia triacanthos (Thornless honeylocust). FireApproved. https://fireapproved.com/plants/gleditsia-triacanthos/. Last verified 2026-08-23.