Podocarpaceae

tree family

Oct 9, 2023 - 23:23
 0  6

celery-top pine

Podocarpaceae, family of 17 or more genera and 125–165 species of conifers (division Pinophyta, order Pinales), ornamental and timber evergreen trees and shrubs distributed mainly in the Southern Hemisphere. The seven main genera are Pherosphaera, Microcachrys, Saxegothaea, Dacrydium, Acmopyle, Podocarpus, and Phyllocladus. All occur in the Australasian region, except Saxegothaea and its relatives (South America); another genus, Afrocarpus, is native to Africa and Madagascar. The Podocarpaceae are usually dioecious (having separate male and female plants) and have leaves variously awl-shaped, needlelike, or broad, with many parallel veins. In the genus Phyllocladus, the foliar leaves are replaced by flattened branchlets (phylloclades) resembling leaves. The staminate, or pollen-bearing, cones are borne in a terminal or axillary position on leafy twigs; the ovulate, or seed-bearing, cones at maturity become fleshy and sometimes brightly coloured and surmount the fleshy cone axis.

The largest genus, Podocarpus, contains about 100 species and is commonly called yellowwood. It is widely distributed in mountain forests of the Southern Hemisphere and occurs as far north as Mexico, southern China, and southern Japan. Dacrydium has about 16 species of Australasian trees and shrubs, including the rimu, or New Zealand red pine. The celery-top pine (Phyllocladus asplenifolius, see photograph) is the best known of the six species of Australasian trees and shrubs in the genus Phyllocladus. The Prince Albert yew (Saxegothaea conspicua), a timber tree native to South America, is the only species in the genus Saxegothaea.

Parasitaxus ustus of New Caledonia, the only species in the genus, is unique among gymnosperms in that it is parasitic upon another genus of Podocarpaceae, Falcatifolium. The roots of Parasitaxus invade those of its host, and the parasite draws water and nutrients from the host’s roots.

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