Gymnosperms

Abstract Gymnosperms are a diverse group of plants with the common characteristic of having a ‘naked’, or unprotected, seed. (This contrasts with the other major seed‐bearing plant group, the angiosperms, whose seeds are enclosed in layers of tissue during development.) Historically common, today only approximately 1000 species exist worldwide. Four broad divisions (cycads, ginkgos, conifers and gnetophytes) are generally recognised. Gymnosperms are found in a wide variety of habitats, throughout most of the world. Many are trees: conifers are mostly evergreen trees with needle‐ or scale‐like leaves; cycads are palm‐like trees; ginkgos are deciduous, broad‐leaved trees and gnetophytes are mostly woody climbers (vines) or shrubs. The conifers are the most significant group of timber‐producing trees, and provide the majority of solid wood products worldwide. The economies of many countries depend on ‘softwood’ lumber derived from conifers. Key Concepts: Gymnosperms are plants with a ‘naked’, or unprotected, seed. Gymnosperms live in a variety of habitats worldwide. There are approximately 1000 species of gymnosperms alive today, in four broad divisions: cycads, ginkgos, conifers and gnetophytes. Many gymnosperms are trees, and some are economically important as a source of timber and pulp. Most gymnosperms are evergreen, woody perennials.