Cephalotaxus

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iCephalotaxus
Cephalotaxus harringtonii
Cephalotaxus harringtonii
Scientific classification
Kingdom: Plantae
Division: Pinophyta
Class: Pinopsida
Order: Pinales
Family: Cephalotaxaceae
Genus: Cephalotaxus
Siebold & Zucc. ex Endl.
Species

Cephalotaxus fortunei
Cephalotaxus griffithii
Cephalotaxus hainanensis
Cephalotaxus harringtonii
Cephalotaxus koreana
Cephalotaxus lanceolata
Cephalotaxus latifolia
Cephalotaxus manni
Cephalotaxus oliveri
Cephalotaxus sinensis
Cephalotaxus wilsoniana

Cephalotaxus (Plum-yew) is a genus of conifers comprising 11 species, treated in either the Cephalotaxaceae, or in the Taxaceae when that family is considered in a broad sense. The genus is endemic to eastern Asia, though fossil evidence shows it had a wider Northern Hemisphere distribution in the past. The species are evergreen shrubs and small trees reaching 1-10 m (rarely to 20 m) tall.

The leaves are spirally arranged on the shoots, but twisted at the base to lie in two flat ranks (except on erect leading shoots); they are linear, 3-11 cm long and 3-4 mm broad, soft in texture, with a blunt tip; this helps distinguish them from the related genus Torreya, which has spine-tipped leaves.

The species can be either monoecious or dioecious; when monoecious, the male and female cones are often on different branches. The male (pollen) cones are 5-8 mm long, grouped in lines along the underside of a shoot. The female (seed) cones are single or grouped 2-15 together on short stems; minute at first, they mature in about 18 months to a drupe-like structure with the single large nut-like seed 1.5-4 cm long surrounded by a fleshy covering, green to purple at full maturity. Natural dispersal is thought to be aided by squirrels which bury the seeds for a winter food source; any seeds left uneaten are then able to germinate.

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