{"id":"rhamnus-frangula","license":"CC-BY-4.0","data":{"scientificName":"Rhamnus frangula","commonNames":["'Fine Line® Improved' buckthorn"],"taxonRank":"species","acceptedName":"Frangula alnus","family":"Rhamnaceae","synonyms":["Rhamnus frangula"],"ids":{"usdaSymbol":"FRAL4","gbifKey":7273688,"itisTsn":504744,"wikidataQid":"Q146136","inatTaxonId":55972},"usdaZoneMin":"2a","usdaZoneMax":"7b","zoneSource":"pnw590","states":["CO","CT","IA","ID","IL","IN","KY","MA","MD","ME","MI","MN","NC","NE","NH","NJ","NY","OH","OR","PA","RI","TN","VT","WA","WI","WV","WY"],"invasiveIn":[{"state":"L48","status":"invasive-reported","source":"us-riis"}],"hardinessAssertions":[{"minimum":"2","maximum":"7","interpretation":"explicit-range","precision":"whole-zone","zoneMapping":"source-stated","applicability":"applicable","source":"osu-em-9103","sourceTaxon":"Rhamnus frangula","taxonMatch":"exact","sourcePlacement":"Alder Buckthorn profile (PDF page 108)","sourceVersion":"EM 9103, February 2015","asOf":"2026-08-26T00:00:00.000Z"},{"minimum":"2","maximum":"7","interpretation":"explicit-range","precision":"whole-zone","zoneMapping":"source-stated","applicability":"applicable","source":"pnw-590","sourceTaxon":"Rhamnus frangula","taxonMatch":"exact","sourcePlacement":"Plant profile USDA hardiness zones field","sourceVersion":"2023-10","asOf":"2026-08-26T00:00:00.000Z"},{"minimum":"3a","interpretation":"minimum-threshold","precision":"half-zone","zoneMapping":"derived-containing-band","sourceMeasurement":{"kind":"minimum-temperature","value":-38,"unit":"degrees-fahrenheit"},"applicability":"applicable","source":"usda-plants-characteristics","sourceRecordId":"FRAL4","sourceTaxon":"Rhamnus frangula","taxonMatch":"source-identifier","sourcePlacement":"PlantCharacteristics record 87224, Temperature, Minimum (°F)","sourceVersion":"PLANTS Help Document 2022; characteristics cache retrieved 2026-08-23","asOf":"2026-08-26T00:00:00.000Z"}],"plantForm":"shrub","matureHeightFt":12,"waterNeed":"moderate","photo":{"file":"/images/plants/rhamnus-frangula.jpg","sourceUrl":"https://www.inaturalist.org/photos/524545891","observationUrl":"https://www.inaturalist.org/observations/291537986","license":"cc0","attribution":"no rights reserved","fetchedOn":"2026-08-23T00:00:00.000Z"},"evidence":[{"source":"pnw-590","verdict":"recommend","verdictRaw":"listed fire-resistant","edition":"2023","url":"https://extension.oregonstate.edu/catalog/pub/pnw-590-fire-resistant-plants-home-landscapes","documentDate":"2023-10-01T00:00:00.000Z","accessedOn":"2026-08-23T00:00:00.000Z"},{"source":"wa-dnr-eastern-wa","verdict":"recommend","verdictRaw":"listed fire-resistant","url":"https://www.dnr.wa.gov/publications/rp_fire_resistant_plants_guide_easternwa.pdf","accessedOn":"2026-08-23T00:00:00.000Z"},{"source":"fps-eastern-us","verdict":"mixed","verdictRaw":"AT RISK Firewise (3)","claims":"Fern-like foliage.","sourcePlacement":{"value":"LZ3","scheme":"fps-landscape-zone"},"edition":"2016-wayback","accessedOn":"2026-08-23T00:00:00.000Z"},{"source":"idaho-firewise-master-db","verdict":"mixed","verdictRaw":"fire-resistance score 6 of 10","score":{"value":6,"scale":"idaho-0-10"},"sourcePlacement":{"value":"plantable at 50' from home","scheme":"idaho-distance"},"url":"https://idahofirewise.org/wp-content/uploads/2017/04/FireXResistanceXofXPlantsXMasterXDatabase.pdf","accessedOn":"2026-08-23T00:00:00.000Z"},{"source":"osu-b921","verdict":"recommend","verdictRaw":"L flammability","claims":"Urban adaptive; sensitive to nematode damage; invasive.","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":"firesmart-bc","verdict":"recommend","verdictRaw":"FireSmart-approved fire-resistant plant","sourcePlacement":{"value":"suitable for HIZ extended zone (30-100 m)","scheme":"firesmart-hiz"},"original":"pnw-590","url":"https://firesmartbc.ca/landscaping-hub/fire-resistant-plants/","accessedOn":"2026-08-23T00:00:00.000Z"},{"source":"dibble-2007-northeastern-invasives","verdict":"recommend","verdictRaw":"low effective heat of combustion (author-named group)","score":{"value":11.45,"scale":"AEHOC-MJ-kg"},"claims":"Conditioned foliage and twigs were tested at 25 kW/m2 in a cone calorimeter.","plantPart":"shoot","condition":"cured","edition":"2007","url":"https://research.fs.usda.gov/download/treesearch/31137.pdf","documentDate":"2007-08-20T00:00:00.000Z","accessedOn":"2026-08-24T00:00:00.000Z"},{"source":"osu-em-9103","verdict":"recommend","verdictRaw":"fire-resistant plants that thrive in Willamette Valley growing conditions","claims":"The shrubs & woody vines profile lists Rhamnus frangula as Alder Buckthorn. The profile prints USDA Hardiness Zone: 2–7.","plantPart":"whole-plant","sourcePlacement":{"value":"Alder Buckthorn profile (PDF page 108)","scheme":"osu-em-9103-profile"},"edition":"EM 9103, February 2015","url":"https://www.canbyfire.org/files/074d2a9e3/Fire-Resistant-Plants_Willamette-Valley.pdf","documentDate":"2015-02-01T00:00:00.000Z","accessedOn":"2026-08-25T00:00:00.000Z"}],"flammabilityClass":"fire-resistant","ratingReason":"consensus","recommendation":"on-list","author":"grayson-graham","reviewStatus":"draft","lastVerified":"2026-08-23T00:00:00.000Z","reviewNotes":"Demoted from on-list 2026-08-23 (Phase 1 lineage audit): evidence rows do not span two verified lineage trees. Evidence retained; returns to the list when a second verified-independent Tier 1 lineage lands. Photo auto-selected (top-voted iNat); human review pending."},"localAssessmentInputs":{"stateDistribution":["CO","CT","IA","ID","IL","IN","KY","MA","MD","ME","MI","MN","NC","NE","NH","NJ","NY","OH","OR","PA","RI","TN","VT","WA","WI","WV","WY"],"nativeStates":[],"rangeAssertions":[{"relation":"documented-occurrence","geography":{"grain":"state","stateCodes":["CO","CT","IA","ID","IL","IN","KY","MA","MD","ME","MI","MN","NC","NE","NH","NJ","NY","OH","OR","PA","RI","TN","VT","WA","WI","WV","WY"]},"provenance":"legacy-field"}],"usdaZoneMin":"2a","usdaZoneMax":"7b","hardinessAssertions":[{"minimum":"2","maximum":"7","interpretation":"explicit-range","precision":"whole-zone","zoneMapping":"source-stated","applicability":"applicable","source":"osu-em-9103","sourceTaxon":"Rhamnus frangula","taxonMatch":"exact","sourcePlacement":"Alder Buckthorn profile (PDF page 108)","sourceVersion":"EM 9103, February 2015","asOf":"2026-08-26T00:00:00.000Z","provenance":"cited"},{"minimum":"2","maximum":"7","interpretation":"explicit-range","precision":"whole-zone","zoneMapping":"source-stated","applicability":"applicable","source":"pnw-590","sourceTaxon":"Rhamnus frangula","taxonMatch":"exact","sourcePlacement":"Plant profile USDA hardiness zones field","sourceVersion":"2023-10","asOf":"2026-08-26T00:00:00.000Z","provenance":"cited"},{"minimum":"3a","interpretation":"minimum-threshold","precision":"half-zone","zoneMapping":"derived-containing-band","sourceMeasurement":{"kind":"minimum-temperature","value":-38,"unit":"degrees-fahrenheit"},"applicability":"applicable","source":"usda-plants-characteristics","sourceRecordId":"FRAL4","sourceTaxon":"Rhamnus frangula","taxonMatch":"source-identifier","sourcePlacement":"PlantCharacteristics record 87224, 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":"2","maximum":"7","interpretation":"explicit-range","precision":"whole-zone","zoneMapping":"source-stated","applicability":"applicable","source":"osu-em-9103","sourceTaxon":"Rhamnus frangula","taxonMatch":"exact","sourcePlacement":"Alder Buckthorn profile (PDF page 108)","sourceVersion":"EM 9103, February 2015","asOf":"2026-08-26T00:00:00.000Z","provenance":"cited"},{"minimum":"2","maximum":"7","interpretation":"explicit-range","precision":"whole-zone","zoneMapping":"source-stated","applicability":"applicable","source":"pnw-590","sourceTaxon":"Rhamnus frangula","taxonMatch":"exact","sourcePlacement":"Plant profile USDA hardiness zones field","sourceVersion":"2023-10","asOf":"2026-08-26T00:00:00.000Z","provenance":"cited"},{"minimum":"3a","interpretation":"minimum-threshold","precision":"half-zone","zoneMapping":"derived-containing-band","sourceMeasurement":{"kind":"minimum-temperature","value":-38,"unit":"degrees-fahrenheit"},"applicability":"applicable","source":"usda-plants-characteristics","sourceRecordId":"FRAL4","sourceTaxon":"Rhamnus frangula","taxonMatch":"source-identifier","sourcePlacement":"PlantCharacteristics record 87224, Temperature, Minimum (°F)","sourceVersion":"PLANTS Help Document 2022; characteristics cache retrieved 2026-08-23","asOf":"2026-08-26T00:00:00.000Z","provenance":"cited"}]},"invasiveIn":[{"state":"L48","status":"invasive-reported","source":"us-riis"}],"statusAssertions":[{"status":"invasive","channel":"ecological","geography":{"grain":"aggregate-region","regions":["L48"]},"source":"us-riis","provenance":"legacy-field"}],"fireEvidenceClass":"fire-resistant","recommendation":"on-list","fireSourceScopes":[{"source":"dibble-2007-northeastern-invasives","sourceName":"Combustion characteristics of north-eastern USA vegetation tested in the cone calorimeter","sourceUrl":"https://research.fs.usda.gov/treesearch/31137","geography":{"grain":"aggregate-region","stateCodes":["ME","MD","MA","NY","VA"],"regions":["Northeastern and mid-Atlantic study sites"]},"completeness":"partial","reviewStatus":"reviewed","scope":"The authors collected foliage and twigs across study sites in Maine, Maryland, Massachusetts, New York, and Virginia, then conditioned and tested the samples in a cone calorimeter. FireApproved publishes 37 exact source owners only as multi-state laboratory context. The source does not establish that every taxon was sampled in every named state, whole-plant behavior, landscape suitability, or state planting guidance.","sourceVersion":"USDA-Treesearch-31137-2007","asOf":"2007-08-20T00:00:00.000Z"},{"source":"idaho-firewise-master-db","sourceName":"Fire Resistance of Plants Master Database","sourceUrl":"https://idahofirewise.org/wp-content/uploads/2017/04/FireXResistanceXofXPlantsXMasterXDatabase.pdf","geography":{"grain":"aggregate-region","stateCodes":["ID"],"regions":["Southern Idaho"]},"completeness":"partial","reviewStatus":"reviewed","scope":"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.","sourceVersion":"Idaho-Firewise-Southern-Idaho-Master-2013-11-08","asOf":"2013-11-08T00:00:00.000Z"},{"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":"osu-em-9103","sourceName":"Fire-resistant Landscape Plants for the Willamette Valley (EM 9103)","sourceUrl":"https://www.canbyfire.org/files/074d2a9e3/Fire-Resistant-Plants_Willamette-Valley.pdf","geography":{"grain":"aggregate-region","stateCodes":["OR"],"regions":["Willamette Valley"]},"completeness":"partial","reviewStatus":"reviewed","scope":"OSU Extension says EM 9103 highlights fire-resistant plants that thrive under Willamette Valley growing conditions. FireApproved publishes 172 exact owners only as valley context. The guide shares the PNW 590 lineage and is not a second independent vote or statewide site clearance.","sourceVersion":"OSU-EM-9103-2015-02","asOf":"2015-02-01T00:00:00.000Z"},{"source":"pnw-590","sourceName":"Fire-Resistant Plants for Home Landscapes (PNW 590)","sourceUrl":"https://extension.oregonstate.edu/catalog/pub/pnw-590-fire-resistant-plants-home-landscapes","geography":{"grain":"state","stateCodes":["ID","OR","WA"]},"completeness":"partial","reviewStatus":"reviewed","scope":"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.","sourceVersion":"PNW-590-October-2023","asOf":"2023-10-01T00:00:00.000Z"},{"source":"wa-dnr-eastern-wa","sourceName":"Fire-Resistant Plants for Eastern Washington","sourceUrl":"https://dnr.wa.gov/publications/rp_fire_resistant_plants_guide_easternwa.pdf","geography":{"grain":"aggregate-region","stateCodes":["WA"],"regions":["Eastern Washington"]},"completeness":"partial","reviewStatus":"reviewed","scope":"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.","sourceVersion":"WA-DNR-Eastern-Washington-live-2026-08-26"}],"firePerformanceConditions":[{"condition":"cured","evidence":[{"source":"dibble-2007-northeastern-invasives","verdict":"recommend","url":"https://research.fs.usda.gov/download/treesearch/31137.pdf","claims":"Conditioned foliage and twigs were tested at 25 kW/m2 in a cone calorimeter.","evidenceIndex":6}]}],"maintenanceAssertions":[],"maintenanceConditions":null,"regulatoryReviews":{},"seedReviews":{}},"legacyCompatibilityProjection":{"nativeStates":[],"invasiveIn":[{"state":"L48","status":"invasive-reported","source":"us-riis"}]},"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."}