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A mature female big-cone pine (Pinus coulteri) cone, the heaviest pine cone A young female or seed cone on a Norway spruce (Picea abies) Immature male or pollen cones of Swiss pine (Pinus cembra) A conifer cone or, in formal botanical usage, a strobilus , pl. : strobili , is a seed-bearing organ on gymnosperm plants, especially in conifers and ...
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.
Gnetophyta (/ n ɛ ˈ t ɒ f ɪ t ə, ˈ n ɛ t oʊ f aɪ t ə /) is a division of plants (alternatively considered the subclass Gnetidae or order Gnetales), grouped within the gymnosperms (which also includes conifers, cycads, and ginkgos), that consists of some 70 species across the three relict genera: Gnetum (family Gnetaceae), Welwitschia (family Welwitschiaceae), and Ephedra (family ...
Encephalartos sclavoi cone, about 30 cm long. Over 1,000 living species of gymnosperm exist. [2] 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.
Diagram of archegonium anatomy. An archegonium (pl.: archegonia), from the Ancient Greek ἀρχή ("beginning") and γόνος ("offspring"), is a multicellular structure or organ of the gametophyte phase of certain plants, producing and containing the ovum or female gamete.
This results in a scale like appearance. Two forms of woody cones act as the gametophyte structures, which mature approximately six months after pollination and are typically retained on the tree for up to one year. The female cones are spherical with pointed bract scales 12–15 mm in diameter. The male cones are much smaller 3–5 mm in diameter.
Cone collecting is extremely seasonal and unpredictable. The time window to pick cones from trees when they are perfectly ripe can be as short as a week, even days. Collectors are racing against ...
Cross section of ovule in gymnosperms and angiosperms. Gymnosperm pollen is produced in microsporangia borne on the scales of the male cone or microstrobilus.In most species, the plants are wind-pollinated, and the pollen grains of conifers have air bladders that provide buoyancy in air currents.