Usually evergreen, occasionally deciduous trees and shrubs. Trunk usually freely branched. Leaves simple, usually narrow. Male sporangia borne on sporophylls arranged in strobili. Female sporangia borne in naked ovules, either singly and terminally or borne on scales in female strobili, the fertilised ovule being retained on the sporophyte until ripe.

The Pinophyta, commonly known as conifers or firtrees, are woody, usually evergreen trees and shrubs with secondary thickening and xylem without vessels. The relatively large development of the trunk as compared with that of the branches is characteristic of many species. The mature wood is distinguished from that of the flowering plant trees by the absence of vessels and is composed of tracheids or elongated spindle-shaped cells with closed ends, which are dove-tailed between one another. They have woody walls marked with bordered pits. The medullary rays traversing the wood are usually only one cell thick and rarely visible without magnification. In some genera resin ducts are conspicuous as small spots on the transverse surface of the wood. Heartwood and sapwood are not always easily distinguished. The branches are verticillate, usually patent, and often gradually get smaller upwards, thus producing a conical outline to the tree. As it gets older the tree often loses its lower branches and the branches of the apex become less regular. Whether the ends of the branches are erect, ascending, upswept, spreading, drooping, sloping down or hanging is often characteristic of the species and can make identification possible at a distance. The above adjectives seem more appropriate than any technical terms. The young shoots vary greatly in colour and degree of hairiness in the different species and are usually markedly different from the older twigs.

The buds are like those of flowering plant trees. The leading shoot often has a terminal bud surrounded by smaller buds; in lateral shoots the terminal bud is often accompanied by two smaller buds, which sometimes remain dormant. The colour and shape of the bud-scales and whether they secrete resin or not are often good specific characters.