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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.
Glyptolepis is an extinct morphogenus of female conifer cones from the Triassic. It was established in 1872 by the French botanist Wilhelm Philippe Schimper . [ 1 ] [ 2 ] [ 3 ] The morphogenus is characterized by having bract scale complexes with elongated seed scale stalks.
To fertilize the ovum, the male cone releases pollen that is carried in the wind to the female cone. This is pollination. (Male and female cones usually occur on the same plant.) The pollen fertilizes the female gamete (located in the female cone). Fertilization in some species does not occur until 15 months after pollination. [23]
Strobili are often called cones, but some botanists restrict the use of the term cone to the woody seed strobili of conifers. Strobili are characterized by a central axis (anatomically a stem ) surrounded by spirally arranged or decussate structures that may be modified leaves or modified stems .
The trees' pollen cones appear in April and mature in September or October. [17] The cones require fifteen months to mature, [18] and the cones fall 17 to 18 months after pollination in late January to early March from the coast to the current Bunya Mountains. When there is heavy rainfall or drought, pollination may vary. [19]
The female cones (seed), which mature in autumn about 18 months after pollination, are globose, large, 18–25 cm (7–10 in) in diameter, and hold about 100–150 seeds. The cones disintegrate at maturity to release the approximately 5 cm (2 in) long nut -like seeds, which are then dispersed by animals, notably the azure jay , Cyanocorax ...
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]
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.