The Sugar Pine (Pinus lambertiana; family Pinaceae) is a species of pine that occurs in the mountains of Oregon and California in the western United States, and Baja California in northwestern Mexico; specifically the Sierra Nevada, the Cascade Range, the Coast Ranges, and the Sierra San Pedro Martir.

This tree is the largest species of pine, commonly growing to 40-60 m tall, exceptionally up to 81 m tall, and with a trunk diameter of 1.5-2.5 m, exceptionally 3.5 m.

It is a member of the white pine group, Pinus subgenus Strobus, and like all members of that group, the leaves ('needles') are in fascicles (bundles) of five, with a deciduous sheath. They are 6-11 cm long. Sugar Pine is notable for having the longest cones of any conifer, mostly 25-50 cm long, exceptionally up to 66 cm long. The seeds are 10-12 mm long, with a 2-3 cm long wing that aids wind dispersal.

The Sugar Pine has been severely affected by the White Pine Blister Rust (Cronartium ribicola), a fungus that was accidentally introduced from Europe in 1909. A high proportion of the Sugar Pine has been killed by the blister rust, particularly in the northern part of the species' range (further south in central and southern California, the summers are too dry for the disease to spread easily). The rust has also destroyed much of the Western White Pine and Whitebark Pine outside of California. The US Forest Service has a program (see link below) for developing rust-resistant Sugar Pine and Western White Pine. Seedlings of these trees have been introduced into the wild.

External links

• Arboretum de Villardebelle - cone photo
• Gymnosperm Database - Pinus lambertiana
• US Forest Service, Dorena Genetic Resource Center (rust resistance program)