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Arborvitaes Thuja

The rated Thuja records split: 0 fire-resistant, 1 keep-away, 2 in documented conflict. These counts describe the cited records — 4 records carrying 50 evidence rows from 18 cited sources; they do not make one verdict for the genus.

Rated as a group: Arborvitae Thuja sp. Keep away Consensus 6 sources rate the genus as a whole. Species evidence never rolls upward into a genus verdict, and genus claims never override a species record. ›
Documented conflict

2 species

honest ties — treat conservatively near structures
Awaiting evidence

1 species

About arborvitaes

Corpus context. Thuja is the directory's #241 largest of 550 genus groups: 4 records carrying 50 evidence rows from 18 cited sources, recorded as tree, shrub , hardy across USDA zones 3–5. Recorded trait flags: 1 carry resinous foliage flags; 1 carry traps dead material flags — each cited on its page. Those are corpus facts, not a whole-genus flammability claim.

More about Thuja: Wikipedia — external references; not evidence sources.

Where rated arborvitaes grow

Tagged as growing in 32 states.

Two-panel identification comparison. Left, a Juniperus scopulorum branch traced from a 1915 USDA plate — rounded three-dimensional sprays with round berry-like cones ringed in accent. Right, a Thuja plicata branch traced from Sudworth's 1908 plate — flattened fanlike sprays with a cluster of small open cones ringed in accent. A bottom band notes that bark does not distinguish the two.
FA Exhibit ID-001. Juniper or redcedar? The scale-leaf lookalikes. Claims quoted from USFS FEIS species reviews (Scher 2002, Juniperus scopulorum; Tesky 1992, Thuja plicata). Specimen art traced from public-domain USDA plates — Bulletin 207 (1915) Plate IX and Sudworth, Forest Trees of the Pacific Slope (1908), Fig. 60 — via Internet Archive / Wikimedia Commons. Identification only — no flammability claim. Confirm uncertain material with a regional key or a botanist. CC BY 4.0.

See Thuja on Grow → · JSON