Description from Flora of China
Trees deciduous; branches irregularly whorled, spreading; branchlets strongly dimorphic: long branchlets with leaves present only in 1st year, older parts with leaves in dense tufts on lateral short branchlets developed from axillary buds. Leaves spirally arranged on long branchlets, in dense clusters of 15-50 or more on short branchlets, sessile, turning yellow and falling in autumn, linear-needlelike, flattened, longitudinally keeled adaxially, sometimes also slightly so abaxially, ca. 1.8 mm wide, flexible, stomatal lines abaxial or on each surface, vascular bundle 1, resin canals 2, usually marginal. Cones borne at apex of short branchlets, solitary. Pollen not saccate, with a narrow, equatorial ridge. Seed cones shortly pedunculate, usually erect, purplish, reddish, or rarely green, maturing in 1st year. Seed scales thin, ± leathery, opening to release seeds, persistent. Bracts included or exserted, ovate or lanceolate, midvein prominent abaxially, forming an apical cusp. Seeds small; wing persistent, relatively long, membranous. Cotyledons 6-8. Germination epigeal. 2n = 24*.
Fifteen species: boreal and temperate regions of Asia, Europe, and North America; 11 species (four endemic, two introduced) in China.