Dichotomous Key/Pinaceae

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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