Jepson eFlora: Taxon page
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Tsuga heterophylla

Higher Taxonomy
Family: PinaceaeView DescriptionDichotomous Key

Common Name: PINE FAMILY
Habit: Shrub, tree, evergreen; monoecious. Stem: young crown conic; twig not grooved, resinous, generally persistent. Leaf: simple, generally alternate, sometimes in bundles or appearing +- 2-ranked, linear or awl-like; base decurrent, woody or not, persistent several years. Pollen Cone: generally < 6 cm, not woody, deciduous. Seed Cone: generally woody; bracts, scales generally persistent; scale not peltate, fused to or free from subtending bract. Seed: 2, on scale base adaxially.
Genera In Family: 10 genera, 193 species: generally northern hemisphere; many of great commercial value, supplying > 1/2 of world's timber.
eFlora Treatment Author: J. Robert Haller, Nancy J. Vivrette, & James R. Griffin, except as noted
Scientific Editor: Thomas J. Rosatti, Bruce G. Baldwin.
Genus: TsugaView DescriptionDichotomous Key

Common Name: HEMLOCK
Stem: crown conic, top slender, generally nodding; branches +- drooping; bark red-brown; twig with persistent, peg-like leaf bases, hairy or puberulent; bud ovoid. Leaf: 5--25 mm, tapered to a short petiole above persistent base, spreading, +- 2-ranked or not, +- flat, grooved adaxially or not, ridged abaxially. Seed Cone: pendent, 1.2--7.5 cm, ovoid to oblong, opening 1st year; stalk +- 0; bract included, free from scale. Seed: plus wing < 2 cm. Chromosomes: 2n=24.
Species In Genus: 10 species: northern hemisphere. Etymology: (Japanese: hemlock)

Tsuga heterophylla (Raf.) Sarg.
Stem: trunk < 50 m, < 2.7 m wide; mature bark thin, red-brown, grooves narrow, ridges wide; twig hairy. Leaf: 5--20 mm, persistent 4--7 years; tip blunt to rounded.
Ecology: Scattered in northern coastal conifer to mixed-evergreen forests; Elevation: generally < 700 m. Bioregional Distribution: NCo, w KR, NCoRO; Distribution Outside California: to Alaska, Montana.
eFlora Treatment Author: J. Robert Haller, Nancy J. Vivrette, & James R. Griffin
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botanical illustration including Tsuga heterophylla


Citation for this treatment: J. Robert Haller, Nancy J. Vivrette, & James R. Griffin 2017. Tsuga heterophylla, in Jepson Flora Project (eds.) Jepson eFlora,, accessed on April 26, 2017.

Citation for the whole project: Jepson Flora Project (eds.) 2017. Jepson eFlora,, accessed on April 26, 2017.

Geographic subdivisions for Tsuga heterophylla:
NCo, w KR, NCoRO;
Markers link to CCH specimen records. Yellow markers indicate records that may provide evidence for eFlora range revision or may have georeferencing or identification issues. Purple markers indicate specimens collected from a garden, greenhouse, or other non-wild location.
map of distribution 1
(Note: any qualifiers in the taxon distribution description, such as 'northern', 'southern', 'adjacent' etc., are not reflected in the map above, and in some cases indication of a taxon in a subdivision is based on a single collection or author-verified occurence).

View elevation by latitude chart
Data provided by the participants of the Consortium of California Herbaria.
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CCH collections by month

Duplicates counted once; synonyms included.
Species do not include records of infraspecific taxa.
Blue line denotes eFlora flowering time.