General: Pine family (Pinaceae). Monterey pines are native to California and Baja California where they occur in only a few small populations. Mature Monterey pines can reach 38 m in height with trunks up to 2 m in diameter. The young trees begin as compact pyramids but age into varied shapes. The adult canopy is usually rounded to flat-topped. Along the Pacific coast, the winds sculpt Monterey pine canopies into picturesque shapes. The bark is red-brown to blackish brown and has deep furrows. The leaves are glossy, dark green needles, 6-15 cm long that grow in bundles of three. Needles on older trees are sometimes a bluish green. Flowers appear in late winter or early spring. The trees are monoecious; having both male and female flowers (McDonald & Laacke 1990). The yellow male catkins are 12mm long and are generally found on the lateral branches. Female flowers grow throughout the entire canopy. The grayish brown cones are asymmetrically oval, 6 to 15 cm long, and are born on short stalks in clusters of 3 to 7 cones. The scales are smooth and rounded. Each cone contains from 120 to 200 dark brown to black, bumpy winged seeds that are 6-7mm long. The cones remain closed on the tree until the second year or sometimes longer. Cones generally ripen and open from late winter to early spring of the second year. Thereafter, they may remain on the tree where they can open and close several times depending on temperature and moisture. The close-grained wood is light and soft. Although it is not considered an important lumber tree in California, it has been widely planted in areas with Mediterranean climates throughout the world for use as lumber and pulp.

Distribution: Monterey pines are native to California and Baja California. Native Monterey pine forests occupy a small portion of their historical range and are currently restricted to five coastal locations: Año Nuevo in the north, the Monterey Peninsula, Cambria, and on Guadalupe and Cedros islands off the coast of Baja, California in the south.

For current distribution, please consult the Plant Profile page for this species on the PLANTS Web site.

Habitat: Monterey pines grow below 1200 meters in closed cone pine forests and oak woodlands. The species is one of the 18 California species of pines and cypresses that bear closed cones (Dallman 1998:27). The remaining stands of Monterey pine are threatened by numerous factors including urbanization, recreational development, and fire suppression, pests and diseases. Fire suppression has resulted in very old stands of forest, which are more susceptible to attacks from pests and diseases. In the Monterey area, the trees are seriously threatened by an epidemic of “pine pitch canker”, a fungal disease caused by Fusarium subglutans pini. This fungus was recently introduced to California from the southeastern United States and is carried from tree to tree by several native insects including the Monterey pine cone beetle (Conophthorus radiatae), twig beetles (Pitophthorus spp.) and engraver beetles (Ips spp.). Indigenous stands of Monterey pine are also threatened by genetic contamination, which results from crossbreeding with planted trees that were brought in from other areas.