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All Pinaceae with seeds weighing less than 90 milligrams are seemingly adapted for wind dispersal. Variation in cone size in the family has likely resulted from the variation of seed dispersal mechanisms available in their environments over time. Analysis of Pinaceae cones reveals how selective pressure has shaped the evolution of variable cone size and function throughout the family. Seed dispersal is mostly by wind, but some species have large seeds with reduced wings, and are dispersed by birds. The male cones are small, 0.5–6 cm ( 1⁄ 4– 2 + 1⁄ 4 in) long, and fall soon after pollination pollen dispersal is by wind. The female cones are large and usually woody, 2–60 centimetres (1–24 inches) long, with numerous spirally arranged scales, and two winged seeds on each scale. The embryos of Pinaceae have three to 24 cotyledons. Members of the family Pinaceae are trees (rarely shrubs) growing from 2 to 100 metres (7 to 300 feet) tall, mostly evergreen (except the deciduous Larix and Pseudolarix), resinous, monoecious, with subopposite or whorled branches, and spirally arranged, linear (needle-like) leaves. Major centres of diversity are found in the mountains of southwest China, Mexico, central Japan, and California.Ĭultivated pine forest in Vagamon, southern Western Ghats, Kerala, India

One species, Pinus merkusii, grows just south of the equator in Southeast Asia. The family often forms the dominant component of boreal, coastal, and montane forests. They are the largest extant conifer family in species diversity, with between 220 and 250 species (depending on taxonomic opinion) in 11 genera, and the second-largest (after Cupressaceae) in geographical range, found in most of the Northern Hemisphere, with the majority of the species in temperate climates, but ranging from subarctic to tropical. Pinaceae are supported as monophyletic by their protein-type sieve cell plastids, pattern of proembryogeny, and lack of bioflavonoids. The family is included in the order Pinales, formerly known as Coniferales. The Pinaceae, or pine family, are conifer trees or shrubs, including many of the well-known conifers of commercial importance such as cedars, firs, hemlocks, larches, pines and spruces. Larix (golden), Abies (central foreground) and Pinus (right foreground)