Cephalotaxus
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 Cephalotaxus harringtonii
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Cephalotaxus fortunei |
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.
