{"id":"thuja-occidentalis","license":"CC-BY-4.0","data":{"scientificName":"Thuja occidentalis","commonNames":["Arborvitae"],"taxonRank":"species","acceptedName":"Thuja occidentalis","family":"Cupressaceae","ids":{"usdaSymbol":"THOC2","gbifKey":2684178,"itisTsn":505490,"wikidataQid":"Q147468","inatTaxonId":54037},"usdaZoneMin":"3b","zoneSource":"usda-plants","states":["CT","IA","ID","IL","IN","KY","MA","MD","ME","MI","MN","NC","NH","NJ","NY","OH","OR","PA","RI","SC","TN","VA","VT","WA","WI","WV"],"rangeAssertions":[{"relation":"native","geography":{"grain":"state","stateCodes":["CT"],"regions":["TDWG level 1 7 — NORTHERN AMERICA","TDWG level 2 75 — Northeastern U.S.A.","TDWG level 3 CNT — Connecticut"]},"occurrenceStatus":"present","presenceStatus":"extant","source":"wcvp-v16","sourceVersion":"16","asOf":"2026-06-04T00:00:00.000Z"},{"relation":"native","geography":{"grain":"state","stateCodes":["IL"],"regions":["TDWG level 1 7 — NORTHERN AMERICA","TDWG level 2 74 — North-Central U.S.A.","TDWG level 3 ILL — Illinois"]},"occurrenceStatus":"present","presenceStatus":"extant","source":"wcvp-v16","sourceVersion":"16","asOf":"2026-06-04T00:00:00.000Z"},{"relation":"native","geography":{"grain":"state","stateCodes":["IN"],"regions":["TDWG level 1 7 — NORTHERN AMERICA","TDWG level 2 75 — Northeastern U.S.A.","TDWG level 3 INI — Indiana"]},"occurrenceStatus":"present","presenceStatus":"extant","source":"wcvp-v16","sourceVersion":"16","asOf":"2026-06-04T00:00:00.000Z"},{"relation":"native","geography":{"grain":"state","stateCodes":["KY"],"regions":["TDWG level 1 7 — NORTHERN AMERICA","TDWG level 2 78 — Southeastern U.S.A.","TDWG level 3 KTY — Kentucky"]},"occurrenceStatus":"present","presenceStatus":"extant","source":"wcvp-v16","sourceVersion":"16","asOf":"2026-06-04T00:00:00.000Z"},{"relation":"native","geography":{"grain":"state","stateCodes":["MA"],"regions":["TDWG level 1 7 — NORTHERN AMERICA","TDWG level 2 75 — Northeastern U.S.A.","TDWG level 3 MAS — Massachusetts"]},"occurrenceStatus":"present","presenceStatus":"extant","source":"wcvp-v16","sourceVersion":"16","asOf":"2026-06-04T00:00:00.000Z"},{"relation":"native","geography":{"grain":"state","stateCodes":["MD"],"regions":["TDWG level 1 7 — NORTHERN AMERICA","TDWG level 2 78 — Southeastern U.S.A.","TDWG level 3 MRY — Maryland"]},"occurrenceStatus":"present","presenceStatus":"extant","source":"wcvp-v16","sourceVersion":"16","asOf":"2026-06-04T00:00:00.000Z"},{"relation":"native","geography":{"grain":"state","stateCodes":["ME"],"regions":["TDWG level 1 7 — NORTHERN AMERICA","TDWG level 2 75 — Northeastern U.S.A.","TDWG level 3 MAI — Maine"]},"occurrenceStatus":"present","presenceStatus":"extant","source":"wcvp-v16","sourceVersion":"16","asOf":"2026-06-04T00:00:00.000Z"},{"relation":"native","geography":{"grain":"state","stateCodes":["MI"],"regions":["TDWG level 1 7 — NORTHERN AMERICA","TDWG level 2 75 — Northeastern U.S.A.","TDWG level 3 MIC — Michigan"]},"occurrenceStatus":"present","presenceStatus":"extant","source":"wcvp-v16","sourceVersion":"16","asOf":"2026-06-04T00:00:00.000Z"},{"relation":"native","geography":{"grain":"state","stateCodes":["MN"],"regions":["TDWG level 1 7 — NORTHERN AMERICA","TDWG level 2 74 — North-Central U.S.A.","TDWG level 3 MIN — Minnesota"]},"occurrenceStatus":"present","presenceStatus":"extant","source":"wcvp-v16","sourceVersion":"16","asOf":"2026-06-04T00:00:00.000Z"},{"relation":"native","geography":{"grain":"state","stateCodes":["NC"],"regions":["TDWG level 1 7 — NORTHERN AMERICA","TDWG level 2 78 — Southeastern U.S.A.","TDWG level 3 NCA — North Carolina"]},"occurrenceStatus":"present","presenceStatus":"extant","source":"wcvp-v16","sourceVersion":"16","asOf":"2026-06-04T00:00:00.000Z"},{"relation":"native","geography":{"grain":"state","stateCodes":["NH"],"regions":["TDWG level 1 7 — NORTHERN AMERICA","TDWG level 2 75 — Northeastern U.S.A.","TDWG level 3 NWH — New Hampshire"]},"occurrenceStatus":"present","presenceStatus":"extant","source":"wcvp-v16","sourceVersion":"16","asOf":"2026-06-04T00:00:00.000Z"},{"relation":"native","geography":{"grain":"state","stateCodes":["NJ"],"regions":["TDWG level 1 7 — NORTHERN AMERICA","TDWG level 2 75 — Northeastern U.S.A.","TDWG level 3 NWJ — New Jersey"]},"occurrenceStatus":"present","presenceStatus":"extant","source":"wcvp-v16","sourceVersion":"16","asOf":"2026-06-04T00:00:00.000Z"},{"relation":"native","geography":{"grain":"state","stateCodes":["NY"],"regions":["TDWG level 1 7 — NORTHERN AMERICA","TDWG level 2 75 — Northeastern U.S.A.","TDWG level 3 NWY — New York"]},"occurrenceStatus":"present","presenceStatus":"extant","source":"wcvp-v16","sourceVersion":"16","asOf":"2026-06-04T00:00:00.000Z"},{"relation":"native","geography":{"grain":"state","stateCodes":["OH"],"regions":["TDWG level 1 7 — NORTHERN AMERICA","TDWG level 2 75 — Northeastern U.S.A.","TDWG level 3 OHI — Ohio"]},"occurrenceStatus":"present","presenceStatus":"extant","source":"wcvp-v16","sourceVersion":"16","asOf":"2026-06-04T00:00:00.000Z"},{"relation":"native","geography":{"grain":"state","stateCodes":["PA"],"regions":["TDWG level 1 7 — NORTHERN AMERICA","TDWG level 2 75 — Northeastern U.S.A.","TDWG level 3 PEN — Pennsylvania"]},"occurrenceStatus":"present","presenceStatus":"extant","source":"wcvp-v16","sourceVersion":"16","asOf":"2026-06-04T00:00:00.000Z"},{"relation":"native","geography":{"grain":"state","stateCodes":["RI"],"regions":["TDWG level 1 7 — NORTHERN AMERICA","TDWG level 2 75 — Northeastern U.S.A.","TDWG level 3 RHO — Rhode I."]},"occurrenceStatus":"present","presenceStatus":"extant","source":"wcvp-v16","sourceVersion":"16","asOf":"2026-06-04T00:00:00.000Z"},{"relation":"native","geography":{"grain":"state","stateCodes":["TN"],"regions":["TDWG level 1 7 — NORTHERN AMERICA","TDWG level 2 78 — Southeastern U.S.A.","TDWG level 3 TEN — Tennessee"]},"occurrenceStatus":"present","presenceStatus":"extant","source":"wcvp-v16","sourceVersion":"16","asOf":"2026-06-04T00:00:00.000Z"},{"relation":"native","geography":{"grain":"state","stateCodes":["VA"],"regions":["TDWG level 1 7 — NORTHERN AMERICA","TDWG level 2 78 — Southeastern U.S.A.","TDWG level 3 VRG — Virginia"]},"occurrenceStatus":"present","presenceStatus":"extant","source":"wcvp-v16","sourceVersion":"16","asOf":"2026-06-04T00:00:00.000Z"},{"relation":"native","geography":{"grain":"state","stateCodes":["VT"],"regions":["TDWG level 1 7 — NORTHERN AMERICA","TDWG level 2 75 — Northeastern U.S.A.","TDWG level 3 VER — Vermont"]},"occurrenceStatus":"present","presenceStatus":"extant","source":"wcvp-v16","sourceVersion":"16","asOf":"2026-06-04T00:00:00.000Z"},{"relation":"native","geography":{"grain":"state","stateCodes":["WI"],"regions":["TDWG level 1 7 — NORTHERN AMERICA","TDWG level 2 74 — North-Central U.S.A.","TDWG level 3 WIS — Wisconsin"]},"occurrenceStatus":"present","presenceStatus":"extant","source":"wcvp-v16","sourceVersion":"16","asOf":"2026-06-04T00:00:00.000Z"},{"relation":"native","geography":{"grain":"state","stateCodes":["WV"],"regions":["TDWG level 1 7 — NORTHERN AMERICA","TDWG level 2 75 — Northeastern U.S.A.","TDWG level 3 WVA — West Virginia"]},"occurrenceStatus":"present","presenceStatus":"extant","source":"wcvp-v16","sourceVersion":"16","asOf":"2026-06-04T00:00:00.000Z"}],"hardinessAssertions":[{"minimum":"5","interpretation":"ambiguous-single-value","precision":"whole-zone","zoneMapping":"source-stated","applicability":"uncertain","applicabilityNotes":"The recovered selector prints one Cold Hardiness Zone value but does not define it as a minimum threshold or a one-zone range.","source":"fps-eastern-us","sourceRecordId":"thuja-occidentalis","sourceTaxon":"Thuja occidentalis","taxonMatch":"exact","sourcePlacement":"Cold Hardiness Zone field in the recovered selector record","sourceVersion":"2016-wayback","asOf":"2026-08-26T00:00:00.000Z"},{"minimum":"3","maximum":"7","interpretation":"explicit-range","precision":"whole-zone","zoneMapping":"source-stated","applicability":"applicable","source":"msu-e2948","sourceRecordId":"tree:Thuja occidentalis","sourceTaxon":"Thuja occidentalis","taxonMatch":"exact","sourcePlacement":"Table 1, tree row","sourceVersion":"New, January 2007","asOf":"2026-08-26T00:00:00.000Z"},{"minimum":"3b","interpretation":"minimum-threshold","precision":"half-zone","zoneMapping":"derived-containing-band","sourceMeasurement":{"kind":"minimum-temperature","value":-33,"unit":"degrees-fahrenheit"},"applicability":"applicable","source":"usda-plants-characteristics","sourceRecordId":"THOC2","sourceTaxon":"Thuja occidentalis","taxonMatch":"source-identifier","sourcePlacement":"PlantCharacteristics record 15299, Temperature, Minimum (°F)","sourceVersion":"PLANTS Help Document 2022; characteristics cache retrieved 2026-08-23","asOf":"2026-08-26T00:00:00.000Z"}],"plantForm":"shrub","matureHeightFt":50,"waterNeed":"moderate","traits":["resinous","dead-material-trap"],"photo":{"file":"/images/plants/thuja-occidentalis.jpg","sourceUrl":"https://www.inaturalist.org/photos/258974747","observationUrl":"https://www.inaturalist.org/observations/150216358","license":"cc-by","attribution":"(c) Tom Norton, some rights reserved (CC BY)","fetchedOn":"2026-08-23T00:00:00.000Z"},"evidence":[{"source":"grants-pass","verdict":"avoid","verdictRaw":"listed highly flammable","url":"https://www.grantspassoregon.gov/289/Fire-Resistant-vs-Highly-Flammable-Plant","accessedOn":"2026-08-23T00:00:00.000Z"},{"source":"ashland-best-practices","verdict":"avoid","verdictRaw":"listed highly flammable","url":"https://www.ashlandoregon.gov/919/Best-Practices-for-Fire-Resistant-Landsc","accessedOn":"2026-08-23T00:00:00.000Z"},{"source":"fps-eastern-us","verdict":"avoid","verdictRaw":"NOT Firewise (4)","claims":"Commonly used upright landscape evergreen-multi-stem form opens in heavy snow-very susceptable to bagworms.","sourcePlacement":{"value":"LZ3","scheme":"fps-landscape-zone"},"edition":"2016-wayback","accessedOn":"2026-08-23T00:00:00.000Z"},{"source":"osu-b921","verdict":"avoid","verdictRaw":"H flammability","claims":"Requires good drainage; pH adaptive; drought tolerant.","sourcePlacement":{"value":"keep 30 ft from the home (Zone 3)","scheme":"b921-siting"},"edition":"2006","url":"http://web.archive.org/web/20070714035936/http://www.firewise.org/usa/files/ohio_plantlist.pdf","accessedOn":"2026-08-23T00:00:00.000Z"},{"source":"va-firescapes","verdict":"avoid","verdictRaw":"H flammability","claims":"Requires good drainage. Not heat tolerant.","edition":"2009","url":"http://web.archive.org/web/20090709143736/http://pubs.ext.vt.edu/430/430-300/430-300.pdf","accessedOn":"2026-08-23T00:00:00.000Z"},{"source":"msu-e2948","verdict":"recommend","verdictRaw":"considered wildfire-resistant and are recommended for Michigan’s climate","claims":"Table 1 rows: Thuja occidentalis (American arborvitae); Thuja occidentalis (American arborvitae).","edition":"New, January 2007","url":"https://web.archive.org/web/20070714035839/http://www.firewise.org/usa/files/mi_wildfire_resistant.pdf","documentDate":"2007-01-01T00:00:00.000Z","accessedOn":"2026-08-25T00:00:00.000Z"},{"source":"flamits","verdict":"not-rated","verdictRaw":"time to flaming (s): 63.09","score":{"value":63.09,"scale":"FLAMITS — time to flaming (s)"},"claims":"FLAMITS record 3665; Ignitability measurement; plant part leaves; fuel all; predrying yes; device epiradiator; site Ganteaume2018-1; sampling summer. Primary study Ganteaume2018: Ganteaume, A. (2018). Does plant flammability differ between leaf and litter bed scale? Role of fuel characteristics and consequences for flammability assessment. International Journal of Wildland Fire, 27, 342-352.","plantPart":"leaf","original":"Ganteaume2018","edition":"Dryad version 9","url":"https://doi.org/10.5061/dryad.h18931zr3","documentDate":"2023-12-22T00:00:00.000Z","accessedOn":"2026-08-25T00:00:00.000Z"},{"source":"flamits","verdict":"not-rated","verdictRaw":"flaming duration (s): 90.86","score":{"value":90.86,"scale":"FLAMITS — flaming duration (s)"},"claims":"FLAMITS record 3680; Sustainability measurement; plant part leaves; fuel all; predrying yes; device epiradiator; site Ganteaume2018-1; sampling summer. Primary study Ganteaume2018: Ganteaume, A. (2018). Does plant flammability differ between leaf and litter bed scale? Role of fuel characteristics and consequences for flammability assessment. International Journal of Wildland Fire, 27, 342-352.","plantPart":"leaf","original":"Ganteaume2018","edition":"Dryad version 9","url":"https://doi.org/10.5061/dryad.h18931zr3","documentDate":"2023-12-22T00:00:00.000Z","accessedOn":"2026-08-25T00:00:00.000Z"},{"source":"flamits","verdict":"not-rated","verdictRaw":"ignition frequency (%): 33.5","score":{"value":33.5,"scale":"FLAMITS — ignition frequency (%)"},"claims":"FLAMITS record 3695; Ignitability measurement; plant part leaves; fuel all; predrying yes; device epiradiator; site Ganteaume2018-1; sampling summer. Primary study Ganteaume2018: Ganteaume, A. (2018). Does plant flammability differ between leaf and litter bed scale? Role of fuel characteristics and consequences for flammability assessment. International Journal of Wildland Fire, 27, 342-352.","plantPart":"leaf","original":"Ganteaume2018","edition":"Dryad version 9","url":"https://doi.org/10.5061/dryad.h18931zr3","documentDate":"2023-12-22T00:00:00.000Z","accessedOn":"2026-08-25T00:00:00.000Z"},{"source":"flamits","verdict":"not-rated","verdictRaw":"flame propagation: 0.43","score":{"value":0.43,"scale":"FLAMITS — flame propagation"},"claims":"FLAMITS record 3710; Combustibility measurement; plant part leaves; fuel all; predrying yes; device epiradiator; site Ganteaume2018-1; sampling summer. Primary study Ganteaume2018: Ganteaume, A. (2018). Does plant flammability differ between leaf and litter bed scale? Role of fuel characteristics and consequences for flammability assessment. International Journal of Wildland Fire, 27, 342-352.","plantPart":"leaf","original":"Ganteaume2018","edition":"Dryad version 9","url":"https://doi.org/10.5061/dryad.h18931zr3","documentDate":"2023-12-22T00:00:00.000Z","accessedOn":"2026-08-25T00:00:00.000Z"},{"source":"flamits","verdict":"not-rated","verdictRaw":"time to flaming (s): 17.37","score":{"value":17.37,"scale":"FLAMITS — time to flaming (s)"},"claims":"FLAMITS record 3725; Ignitability measurement; plant part leaves; fuel live; predrying no; device epiradiator; site Ganteaume2018-1; sampling summer. Primary study Ganteaume2018: Ganteaume, A. (2018). Does plant flammability differ between leaf and litter bed scale? Role of fuel characteristics and consequences for flammability assessment. International Journal of Wildland Fire, 27, 342-352.","plantPart":"leaf","original":"Ganteaume2018","edition":"Dryad version 9","url":"https://doi.org/10.5061/dryad.h18931zr3","documentDate":"2023-12-22T00:00:00.000Z","accessedOn":"2026-08-25T00:00:00.000Z"},{"source":"flamits","verdict":"not-rated","verdictRaw":"flaming duration (s): 9.36","score":{"value":9.36,"scale":"FLAMITS — flaming duration (s)"},"claims":"FLAMITS record 3740; Sustainability measurement; plant part leaves; fuel live; predrying no; device epiradiator; site Ganteaume2018-1; sampling summer. Primary study Ganteaume2018: Ganteaume, A. (2018). Does plant flammability differ between leaf and litter bed scale? Role of fuel characteristics and consequences for flammability assessment. International Journal of Wildland Fire, 27, 342-352.","plantPart":"leaf","original":"Ganteaume2018","edition":"Dryad version 9","url":"https://doi.org/10.5061/dryad.h18931zr3","documentDate":"2023-12-22T00:00:00.000Z","accessedOn":"2026-08-25T00:00:00.000Z"},{"source":"flamits","verdict":"not-rated","verdictRaw":"ignition frequency (%): 46","score":{"value":46,"scale":"FLAMITS — ignition frequency (%)"},"claims":"FLAMITS record 3755; Ignitability measurement; plant part leaves; fuel live; predrying no; device epiradiator; site Ganteaume2018-1; sampling summer. Primary study Ganteaume2018: Ganteaume, A. (2018). Does plant flammability differ between leaf and litter bed scale? Role of fuel characteristics and consequences for flammability assessment. International Journal of Wildland Fire, 27, 342-352.","plantPart":"leaf","original":"Ganteaume2018","edition":"Dryad version 9","url":"https://doi.org/10.5061/dryad.h18931zr3","documentDate":"2023-12-22T00:00:00.000Z","accessedOn":"2026-08-25T00:00:00.000Z"},{"source":"flamits","verdict":"not-rated","verdictRaw":"time to flaming (s): 2.6","score":{"value":2.6,"scale":"FLAMITS — time to flaming (s)"},"claims":"FLAMITS record 11334; Ignitability measurement; plant part litter; fuel dead; predrying yes; device epiradiator; site Romero2019-1; sampling july. Primary study Romero2019: Romero, B., Fernandez, C., Lecareux, C., Ormeño, E., & Ganteaume, A. (2019). How terpene content affects fuel flammability of wildlandurban interface vegetation. International Journal of Wildland Fire, 28, 614.","plantPart":"litter","original":"Romero2019","edition":"Dryad version 9","url":"https://doi.org/10.5061/dryad.h18931zr3","documentDate":"2023-12-22T00:00:00.000Z","accessedOn":"2026-08-25T00:00:00.000Z"},{"source":"flamits","verdict":"not-rated","verdictRaw":"maximum flame temperature (°C): 612.6","score":{"value":612.6,"scale":"FLAMITS — maximum flame temperature (°C)"},"claims":"FLAMITS record 11340; Combustibility measurement; plant part litter; fuel dead; predrying yes; device epiradiator; site Romero2019-1; sampling july. Primary study Romero2019: Romero, B., Fernandez, C., Lecareux, C., Ormeño, E., & Ganteaume, A. (2019). How terpene content affects fuel flammability of wildlandurban interface vegetation. International Journal of Wildland Fire, 28, 614.","plantPart":"litter","original":"Romero2019","edition":"Dryad version 9","url":"https://doi.org/10.5061/dryad.h18931zr3","documentDate":"2023-12-22T00:00:00.000Z","accessedOn":"2026-08-25T00:00:00.000Z"},{"source":"flamits","verdict":"not-rated","verdictRaw":"flaming duration (s): 19.6","score":{"value":19.6,"scale":"FLAMITS — flaming duration (s)"},"claims":"FLAMITS record 11346; Sustainability measurement; plant part litter; fuel dead; predrying yes; device epiradiator; site Romero2019-1; sampling july. Primary study Romero2019: Romero, B., Fernandez, C., Lecareux, C., Ormeño, E., & Ganteaume, A. (2019). How terpene content affects fuel flammability of wildlandurban interface vegetation. International Journal of Wildland Fire, 28, 614.","plantPart":"litter","original":"Romero2019","edition":"Dryad version 9","url":"https://doi.org/10.5061/dryad.h18931zr3","documentDate":"2023-12-22T00:00:00.000Z","accessedOn":"2026-08-25T00:00:00.000Z"},{"source":"flamits","verdict":"not-rated","verdictRaw":"temperature at flaming (°C): 351.9","score":{"value":351.9,"scale":"FLAMITS — temperature at flaming (°C)"},"claims":"FLAMITS record 11352; Ignitability measurement; plant part litter; fuel dead; predrying yes; device epiradiator; site Romero2019-1; sampling july. Primary study Romero2019: Romero, B., Fernandez, C., Lecareux, C., Ormeño, E., & Ganteaume, A. (2019). How terpene content affects fuel flammability of wildlandurban interface vegetation. International Journal of Wildland Fire, 28, 614.","plantPart":"litter","original":"Romero2019","edition":"Dryad version 9","url":"https://doi.org/10.5061/dryad.h18931zr3","documentDate":"2023-12-22T00:00:00.000Z","accessedOn":"2026-08-25T00:00:00.000Z"},{"source":"flamits","verdict":"not-rated","verdictRaw":"flammability value: 100","score":{"value":100,"scale":"FLAMITS — flammability value"},"claims":"FLAMITS record 11358; Ignitability measurement; plant part litter; fuel dead; predrying yes; device epiradiator; site Romero2019-1; sampling july. Primary study Romero2019: Romero, B., Fernandez, C., Lecareux, C., Ormeño, E., & Ganteaume, A. (2019). How terpene content affects fuel flammability of wildlandurban interface vegetation. International Journal of Wildland Fire, 28, 614.","plantPart":"litter","original":"Romero2019","edition":"Dryad version 9","url":"https://doi.org/10.5061/dryad.h18931zr3","documentDate":"2023-12-22T00:00:00.000Z","accessedOn":"2026-08-25T00:00:00.000Z"},{"source":"flamits","verdict":"not-rated","verdictRaw":"time to flaming (s): 26.3","score":{"value":26.3,"scale":"FLAMITS — time to flaming (s)"},"claims":"FLAMITS record 11364; Ignitability measurement; plant part leaves; fuel live; predrying no; device epiradiator; site Romero2019-1; sampling july. Primary study Romero2019: Romero, B., Fernandez, C., Lecareux, C., Ormeño, E., & Ganteaume, A. (2019). How terpene content affects fuel flammability of wildlandurban interface vegetation. International Journal of Wildland Fire, 28, 614.","plantPart":"leaf","original":"Romero2019","edition":"Dryad version 9","url":"https://doi.org/10.5061/dryad.h18931zr3","documentDate":"2023-12-22T00:00:00.000Z","accessedOn":"2026-08-25T00:00:00.000Z"},{"source":"flamits","verdict":"not-rated","verdictRaw":"maximum flame temperature (°C): 466","score":{"value":466,"scale":"FLAMITS — maximum flame temperature (°C)"},"claims":"FLAMITS record 11371; Combustibility measurement; plant part leaves; fuel live; predrying no; device epiradiator; site Romero2019-1; sampling july. Primary study Romero2019: Romero, B., Fernandez, C., Lecareux, C., Ormeño, E., & Ganteaume, A. (2019). How terpene content affects fuel flammability of wildlandurban interface vegetation. International Journal of Wildland Fire, 28, 614.","plantPart":"leaf","original":"Romero2019","edition":"Dryad version 9","url":"https://doi.org/10.5061/dryad.h18931zr3","documentDate":"2023-12-22T00:00:00.000Z","accessedOn":"2026-08-25T00:00:00.000Z"},{"source":"flamits","verdict":"not-rated","verdictRaw":"flaming duration (s): 18.5","score":{"value":18.5,"scale":"FLAMITS — flaming duration (s)"},"claims":"FLAMITS record 11378; Sustainability measurement; plant part leaves; fuel live; predrying no; device epiradiator; site Romero2019-1; sampling july. Primary study Romero2019: Romero, B., Fernandez, C., Lecareux, C., Ormeño, E., & Ganteaume, A. (2019). How terpene content affects fuel flammability of wildlandurban interface vegetation. International Journal of Wildland Fire, 28, 614.","plantPart":"leaf","original":"Romero2019","edition":"Dryad version 9","url":"https://doi.org/10.5061/dryad.h18931zr3","documentDate":"2023-12-22T00:00:00.000Z","accessedOn":"2026-08-25T00:00:00.000Z"},{"source":"flamits","verdict":"not-rated","verdictRaw":"temperature at flaming (°C): 362.3","score":{"value":362.3,"scale":"FLAMITS — temperature at flaming (°C)"},"claims":"FLAMITS record 11386; Ignitability measurement; plant part leaves; fuel live; predrying no; device epiradiator; site Romero2019-1; sampling july. Primary study Romero2019: Romero, B., Fernandez, C., Lecareux, C., Ormeño, E., & Ganteaume, A. (2019). How terpene content affects fuel flammability of wildlandurban interface vegetation. International Journal of Wildland Fire, 28, 614.","plantPart":"leaf","original":"Romero2019","edition":"Dryad version 9","url":"https://doi.org/10.5061/dryad.h18931zr3","documentDate":"2023-12-22T00:00:00.000Z","accessedOn":"2026-08-25T00:00:00.000Z"},{"source":"flamits","verdict":"not-rated","verdictRaw":"flammability value: 87","score":{"value":87,"scale":"FLAMITS — flammability value"},"claims":"FLAMITS record 11393; Ignitability measurement; plant part leaves; fuel live; predrying no; device epiradiator; site Romero2019-1; sampling july. Primary study Romero2019: Romero, B., Fernandez, C., Lecareux, C., Ormeño, E., & Ganteaume, A. (2019). How terpene content affects fuel flammability of wildlandurban interface vegetation. International Journal of Wildland Fire, 28, 614.","plantPart":"leaf","original":"Romero2019","edition":"Dryad version 9","url":"https://doi.org/10.5061/dryad.h18931zr3","documentDate":"2023-12-22T00:00:00.000Z","accessedOn":"2026-08-25T00:00:00.000Z"}],"flammabilityClass":"mixed-evidence","ratingReason":"disputed","recommendation":"conflict","author":"grayson-graham","reviewStatus":"draft","lastVerified":"2026-08-23T00:00:00.000Z","reviewNotes":"Photo auto-selected (top-voted iNat); human review pending."},"localAssessmentInputs":{"stateDistribution":["CT","IA","ID","IL","IN","KY","MA","MD","ME","MI","MN","NC","NH","NJ","NY","OH","OR","PA","RI","SC","TN","VA","VT","WA","WI","WV"],"nativeStates":[],"rangeAssertions":[{"relation":"native","geography":{"grain":"state","stateCodes":["CT"],"regions":["TDWG level 1 7 — NORTHERN AMERICA","TDWG level 2 75 — Northeastern U.S.A.","TDWG level 3 CNT — Connecticut"]},"occurrenceStatus":"present","presenceStatus":"extant","source":"wcvp-v16","sourceVersion":"16","asOf":"2026-06-04T00:00:00.000Z","provenance":"cited"},{"relation":"native","geography":{"grain":"state","stateCodes":["IL"],"regions":["TDWG level 1 7 — NORTHERN AMERICA","TDWG level 2 74 — North-Central U.S.A.","TDWG level 3 ILL — Illinois"]},"occurrenceStatus":"present","presenceStatus":"extant","source":"wcvp-v16","sourceVersion":"16","asOf":"2026-06-04T00:00:00.000Z","provenance":"cited"},{"relation":"native","geography":{"grain":"state","stateCodes":["IN"],"regions":["TDWG level 1 7 — NORTHERN AMERICA","TDWG level 2 75 — Northeastern U.S.A.","TDWG level 3 INI — Indiana"]},"occurrenceStatus":"present","presenceStatus":"extant","source":"wcvp-v16","sourceVersion":"16","asOf":"2026-06-04T00:00:00.000Z","provenance":"cited"},{"relation":"native","geography":{"grain":"state","stateCodes":["KY"],"regions":["TDWG level 1 7 — NORTHERN AMERICA","TDWG level 2 78 — Southeastern U.S.A.","TDWG level 3 KTY — Kentucky"]},"occurrenceStatus":"present","presenceStatus":"extant","source":"wcvp-v16","sourceVersion":"16","asOf":"2026-06-04T00:00:00.000Z","provenance":"cited"},{"relation":"native","geography":{"grain":"state","stateCodes":["MA"],"regions":["TDWG level 1 7 — NORTHERN AMERICA","TDWG level 2 75 — Northeastern U.S.A.","TDWG level 3 MAS — Massachusetts"]},"occurrenceStatus":"present","presenceStatus":"extant","source":"wcvp-v16","sourceVersion":"16","asOf":"2026-06-04T00:00:00.000Z","provenance":"cited"},{"relation":"native","geography":{"grain":"state","stateCodes":["MD"],"regions":["TDWG level 1 7 — NORTHERN AMERICA","TDWG level 2 78 — Southeastern U.S.A.","TDWG level 3 MRY — Maryland"]},"occurrenceStatus":"present","presenceStatus":"extant","source":"wcvp-v16","sourceVersion":"16","asOf":"2026-06-04T00:00:00.000Z","provenance":"cited"},{"relation":"native","geography":{"grain":"state","stateCodes":["ME"],"regions":["TDWG level 1 7 — NORTHERN AMERICA","TDWG level 2 75 — Northeastern U.S.A.","TDWG level 3 MAI — Maine"]},"occurrenceStatus":"present","presenceStatus":"extant","source":"wcvp-v16","sourceVersion":"16","asOf":"2026-06-04T00:00:00.000Z","provenance":"cited"},{"relation":"native","geography":{"grain":"state","stateCodes":["MI"],"regions":["TDWG level 1 7 — NORTHERN AMERICA","TDWG level 2 75 — Northeastern U.S.A.","TDWG level 3 MIC — Michigan"]},"occurrenceStatus":"present","presenceStatus":"extant","source":"wcvp-v16","sourceVersion":"16","asOf":"2026-06-04T00:00:00.000Z","provenance":"cited"},{"relation":"native","geography":{"grain":"state","stateCodes":["MN"],"regions":["TDWG level 1 7 — NORTHERN AMERICA","TDWG level 2 74 — North-Central U.S.A.","TDWG level 3 MIN — Minnesota"]},"occurrenceStatus":"present","presenceStatus":"extant","source":"wcvp-v16","sourceVersion":"16","asOf":"2026-06-04T00:00:00.000Z","provenance":"cited"},{"relation":"native","geography":{"grain":"state","stateCodes":["NC"],"regions":["TDWG level 1 7 — NORTHERN AMERICA","TDWG level 2 78 — Southeastern U.S.A.","TDWG level 3 NCA — North Carolina"]},"occurrenceStatus":"present","presenceStatus":"extant","source":"wcvp-v16","sourceVersion":"16","asOf":"2026-06-04T00:00:00.000Z","provenance":"cited"},{"relation":"native","geography":{"grain":"state","stateCodes":["NH"],"regions":["TDWG level 1 7 — NORTHERN AMERICA","TDWG level 2 75 — Northeastern U.S.A.","TDWG level 3 NWH — New Hampshire"]},"occurrenceStatus":"present","presenceStatus":"extant","source":"wcvp-v16","sourceVersion":"16","asOf":"2026-06-04T00:00:00.000Z","provenance":"cited"},{"relation":"native","geography":{"grain":"state","stateCodes":["NJ"],"regions":["TDWG level 1 7 — NORTHERN AMERICA","TDWG level 2 75 — Northeastern U.S.A.","TDWG level 3 NWJ — New Jersey"]},"occurrenceStatus":"present","presenceStatus":"extant","source":"wcvp-v16","sourceVersion":"16","asOf":"2026-06-04T00:00:00.000Z","provenance":"cited"},{"relation":"native","geography":{"grain":"state","stateCodes":["NY"],"regions":["TDWG level 1 7 — NORTHERN AMERICA","TDWG level 2 75 — Northeastern U.S.A.","TDWG level 3 NWY — New York"]},"occurrenceStatus":"present","presenceStatus":"extant","source":"wcvp-v16","sourceVersion":"16","asOf":"2026-06-04T00:00:00.000Z","provenance":"cited"},{"relation":"native","geography":{"grain":"state","stateCodes":["OH"],"regions":["TDWG level 1 7 — NORTHERN AMERICA","TDWG level 2 75 — Northeastern U.S.A.","TDWG level 3 OHI — Ohio"]},"occurrenceStatus":"present","presenceStatus":"extant","source":"wcvp-v16","sourceVersion":"16","asOf":"2026-06-04T00:00:00.000Z","provenance":"cited"},{"relation":"native","geography":{"grain":"state","stateCodes":["PA"],"regions":["TDWG level 1 7 — NORTHERN AMERICA","TDWG level 2 75 — Northeastern U.S.A.","TDWG level 3 PEN — Pennsylvania"]},"occurrenceStatus":"present","presenceStatus":"extant","source":"wcvp-v16","sourceVersion":"16","asOf":"2026-06-04T00:00:00.000Z","provenance":"cited"},{"relation":"native","geography":{"grain":"state","stateCodes":["RI"],"regions":["TDWG level 1 7 — NORTHERN AMERICA","TDWG level 2 75 — Northeastern U.S.A.","TDWG level 3 RHO — Rhode I."]},"occurrenceStatus":"present","presenceStatus":"extant","source":"wcvp-v16","sourceVersion":"16","asOf":"2026-06-04T00:00:00.000Z","provenance":"cited"},{"relation":"native","geography":{"grain":"state","stateCodes":["TN"],"regions":["TDWG level 1 7 — NORTHERN AMERICA","TDWG level 2 78 — Southeastern U.S.A.","TDWG level 3 TEN — Tennessee"]},"occurrenceStatus":"present","presenceStatus":"extant","source":"wcvp-v16","sourceVersion":"16","asOf":"2026-06-04T00:00:00.000Z","provenance":"cited"},{"relation":"native","geography":{"grain":"state","stateCodes":["VA"],"regions":["TDWG level 1 7 — NORTHERN AMERICA","TDWG level 2 78 — Southeastern U.S.A.","TDWG level 3 VRG — Virginia"]},"occurrenceStatus":"present","presenceStatus":"extant","source":"wcvp-v16","sourceVersion":"16","asOf":"2026-06-04T00:00:00.000Z","provenance":"cited"},{"relation":"native","geography":{"grain":"state","stateCodes":["VT"],"regions":["TDWG level 1 7 — NORTHERN AMERICA","TDWG level 2 75 — Northeastern U.S.A.","TDWG level 3 VER — Vermont"]},"occurrenceStatus":"present","presenceStatus":"extant","source":"wcvp-v16","sourceVersion":"16","asOf":"2026-06-04T00:00:00.000Z","provenance":"cited"},{"relation":"native","geography":{"grain":"state","stateCodes":["WI"],"regions":["TDWG level 1 7 — NORTHERN AMERICA","TDWG level 2 74 — North-Central U.S.A.","TDWG level 3 WIS — Wisconsin"]},"occurrenceStatus":"present","presenceStatus":"extant","source":"wcvp-v16","sourceVersion":"16","asOf":"2026-06-04T00:00:00.000Z","provenance":"cited"},{"relation":"native","geography":{"grain":"state","stateCodes":["WV"],"regions":["TDWG level 1 7 — NORTHERN AMERICA","TDWG level 2 75 — Northeastern U.S.A.","TDWG level 3 WVA — West Virginia"]},"occurrenceStatus":"present","presenceStatus":"extant","source":"wcvp-v16","sourceVersion":"16","asOf":"2026-06-04T00:00:00.000Z","provenance":"cited"},{"relation":"documented-occurrence","geography":{"grain":"state","stateCodes":["CT","IA","ID","IL","IN","KY","MA","MD","ME","MI","MN","NC","NH","NJ","NY","OH","OR","PA","RI","SC","TN","VA","VT","WA","WI","WV"]},"provenance":"legacy-field"}],"usdaZoneMin":"3b","usdaZoneMax":null,"hardinessAssertions":[{"minimum":"5","interpretation":"ambiguous-single-value","precision":"whole-zone","zoneMapping":"source-stated","applicability":"uncertain","applicabilityNotes":"The recovered selector prints one Cold Hardiness Zone value but does not define it as a minimum threshold or a one-zone range.","source":"fps-eastern-us","sourceRecordId":"thuja-occidentalis","sourceTaxon":"Thuja occidentalis","taxonMatch":"exact","sourcePlacement":"Cold Hardiness Zone field in the recovered selector record","sourceVersion":"2016-wayback","asOf":"2026-08-26T00:00:00.000Z","provenance":"cited"},{"minimum":"3","maximum":"7","interpretation":"explicit-range","precision":"whole-zone","zoneMapping":"source-stated","applicability":"applicable","source":"msu-e2948","sourceRecordId":"tree:Thuja occidentalis","sourceTaxon":"Thuja occidentalis","taxonMatch":"exact","sourcePlacement":"Table 1, tree row","sourceVersion":"New, January 2007","asOf":"2026-08-26T00:00:00.000Z","provenance":"cited"},{"minimum":"3b","interpretation":"minimum-threshold","precision":"half-zone","zoneMapping":"derived-containing-band","sourceMeasurement":{"kind":"minimum-temperature","value":-33,"unit":"degrees-fahrenheit"},"applicability":"applicable","source":"usda-plants-characteristics","sourceRecordId":"THOC2","sourceTaxon":"Thuja occidentalis","taxonMatch":"source-identifier","sourcePlacement":"PlantCharacteristics record 15299, Temperature, Minimum (°F)","sourceVersion":"PLANTS Help Document 2022; characteristics cache retrieved 2026-08-23","asOf":"2026-08-26T00:00:00.000Z","provenance":"cited"}],"hardinessSelection":{"status":"overlapping","assertions":[{"minimum":"3","maximum":"7","interpretation":"explicit-range","precision":"whole-zone","zoneMapping":"source-stated","applicability":"applicable","source":"msu-e2948","sourceRecordId":"tree:Thuja occidentalis","sourceTaxon":"Thuja occidentalis","taxonMatch":"exact","sourcePlacement":"Table 1, tree row","sourceVersion":"New, January 2007","asOf":"2026-08-26T00:00:00.000Z","provenance":"cited"},{"minimum":"3b","interpretation":"minimum-threshold","precision":"half-zone","zoneMapping":"derived-containing-band","sourceMeasurement":{"kind":"minimum-temperature","value":-33,"unit":"degrees-fahrenheit"},"applicability":"applicable","source":"usda-plants-characteristics","sourceRecordId":"THOC2","sourceTaxon":"Thuja occidentalis","taxonMatch":"source-identifier","sourcePlacement":"PlantCharacteristics record 15299, Temperature, Minimum (°F)","sourceVersion":"PLANTS Help Document 2022; characteristics cache retrieved 2026-08-23","asOf":"2026-08-26T00:00:00.000Z","provenance":"cited"}]},"invasiveIn":[],"statusAssertions":[],"fireEvidenceClass":"mixed-evidence","recommendation":"conflict","fireSourceScopes":[{"source":"msu-e2948","sourceName":"Wildfire-resistant Landscape Plants for Michigan (Extension Bulletin E2948)","sourceUrl":"https://web.archive.org/web/20070714035839/http://www.firewise.org/usa/files/mi_wildfire_resistant.pdf","geography":{"grain":"state","stateCodes":["MI"]},"completeness":"partial","reviewStatus":"reviewed","scope":"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.","sourceVersion":"MSU-Extension-E2948-2007","asOf":"2007-01-01T00:00:00.000Z"},{"source":"osu-b921","sourceName":"Firewise Landscaping (OSU Extension Bulletin 921)","sourceUrl":"http://web.archive.org/web/20070714035936/http://www.firewise.org/usa/files/ohio_plantlist.pdf","geography":{"grain":"state","stateCodes":["OH"]},"completeness":"partial","reviewStatus":"reviewed","scope":"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.","sourceVersion":"OSU-Extension-Bulletin-921-2006","asOf":"2006-03-01T00:00:00.000Z"},{"source":"va-firescapes","sourceName":"Virginia Firescapes — Firewise Landscaping for Woodland Homes (430-300)","sourceUrl":"http://web.archive.org/web/20090709143736/http://pubs.ext.vt.edu/430/430-300/430-300.pdf","geography":{"grain":"state","stateCodes":["VA"]},"completeness":"partial","reviewStatus":"reviewed","scope":"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.","sourceVersion":"Virginia-VCE-430-300-2009","asOf":"2009-04-15T00:00:00.000Z"}],"firePerformanceConditions":[],"maintenanceAssertions":[],"maintenanceConditions":null,"regulatoryReviews":{},"seedReviews":{}},"legacyCompatibilityProjection":{"nativeStates":["CT","IL","IN","KY","MA","MD","ME","MI","MN","NC","NH","NJ","NY","OH","PA","RI","TN","VA","VT","WI","WV"],"invasiveIn":[]},"localAssessmentContract":"Compare each dimension separately. State noxious-weed seed designations are material-scoped and never become non-seed plant restrictions, ecological-invasive findings, nursery restrictions, alternatives, product evidence, or fire votes. Introduced/established context is not an invasive warning. Minimum-only hardiness has no inferred maximum; canonical source-temperature conversion is validated and contradictory applicable rows project no primary zone. L48 context applies only to conterminous states and is never exact-state status. Fire-performance conditions are not maintenance advice. FEIS fire-ecology context does not vote in the plant classification. Absence of a status row is not regulatory clearance."}