< Dichotomous Key
1: Pinaceae
- 2: Cones biennial, rarely triennial, with each year's scale growth distinct, forming an umbo on
- each scale. Cone scale base broad, concealing the seeds fully from abaxial view. Seed without
- resin vesicles. Seed wing holding the seed in a pair of claws. Leaves with primary stomatal
- bands adaxial (above the xylem) or equally on both surfaces.......................................................Pinus
- 2: Cones annual, without a distinct umbo. Cone scale base broad, concealing the seeds
- fully from abaxial view. Seed without resin vesicles, blackish. Seed wing holding the seed
- loosely in a cup. Leaves with primary stomatal bands adaxial (above the xylem) or equally on
- both surfaces.........................................................................................................................Picea
- 2: Cones annual, without a distinct umbo. Cone scale base broad, concealing the seeds fully
- from abaxial view. Seed without resin vesicles, whitish. Seed wing holding the seed tightly in a
- cup. Leaves with primary stomatal bands abaxial (below the phloem vessels) only........Subfamily Laricoideae
- 2: Cones annual, without a distinct umbo. Cone scale base narrow, with the seeds partly visible
- in abaxial view. Seed with resin vesicles. Seed wing holding the seed tightly in a cup. Leaves
- with primary stomatal bands abaxial (below the phloem vessels) only..........................Subfamily Abietoideae
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