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A conifer cone, or in formal botanical usage a strobilus, pl.: strobili, is a seed-bearing organ on gymnosperm plants, especially in conifers and cycads. They are usually woody and variously conic, cylindrical, ovoid, to globular, and have scales and bracts arranged around a central axis, but can be fleshy and berry-like.
Most conifers are monoecious, but some are subdioecious or dioecious; all are wind-pollinated. Conifer seeds develop inside a protective cone called a strobilus. The cones take from four months to three years to reach maturity, and vary in size from 2 to 600 millimetres (1 ⁄ 8 to 23 + 5 ⁄ 8 in) long.
Voltziales is an extinct order of conifers.The group contains the ancestral lineages from which modern conifer groups emerged. Voltzialean conifers are divided into two informal groups, the primitive "walchian conifers" like Walchia, where the ovuliferous cone is composed of radial shoots and the more advanced "voltzian voltziales", also known as "transitional conifers" where the cone is ...
Encephalartos sclavoi cone, about 30 cm long. Over 1,000 living species of gymnosperm exist. [11] It was previously widely accepted that the gymnosperms originated in the Late Carboniferous period, replacing the lycopsid rainforests of the tropical region, but more recent phylogenetic evidence indicates that they diverged from the ancestors of angiosperms during the Early Carboniferous.
A strobilus (pl.: strobili) is a structure present on many land plant species consisting of sporangia-bearing structures densely aggregated along a stem.Strobili are often called cones, but some botanists restrict the use of the term cone to the woody seed strobili of conifers.
Cheirolepidiaceae (also spelled Cheirolepidaceae) is an extinct family of conifers.They first appeared in the Triassic, and were a diverse and common group of conifers during most of the Mesozoic era, primarily at low latitudes, [1] where they often formed a dominant element of the vegetation. [2]
Giant sequoia. Silvics of North America (1991), [1] a forest inventory compiled and published by the United States Forest Service, includes many conifers. [a] It superseded Silvics of Forest Trees of the United States (1965), which was the first extensive American tree inventory. [3]
The seed cones are ovoid-cylindric, 2 to 5 cm (3 ⁄ 4 to 2 in) long, with 40 to 80 seed scales; each scale bearing an exserted 4 to 8 mm (3 ⁄ 16 to 5 ⁄ 16 in) bract. The cones are green [ 5 ] to reddish purple when immature, turning brown and the scales opening flat or reflexed to release the seeds when mature, four to six months after ...