Knobcone pine

Individual specimens can live up to a century.[4] The crown is usually conical with a straight trunk. It reaches heights of 8–24 meters (26–79 feet),[5] but can be a shrub on especially poor sites. The bark is thin and smooth, flaky and gray-brown when young, becoming dark[4] gray-red-brown and shallowly furrowed into flat scaly ridges in age. The twigs are red-brown and often resinous. Its wood is knotty and of little interest for lumber.[4]

The leaves are in fascicles of three,[6] needle-like, yellow-green, twisted, and 9–15 centimeters (3+1⁄2–6 in) long. The cones are resin-sealed and irregularly shaped,[4] 8–16 cm (3+1⁄4–6+1⁄4 in) long and clustered in whorls of three to six on the branches. The scales end in a short stout prickle. Cones can sometimes be found attached to the trunk and larger branches.[4]

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  Leaves
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  male cones
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  Cones
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  Knobcone pine cone
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  Plant
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  Habitat

The knobcone pine can be found growing in the dry, rocky soils of southern Oregon and northern California, between 300 and 750 m (980 and 2,460 ft) above sea level.[4] It forms nearly pure stands, preferring to grow where there is no competition.[4]

On the coast, the knobcone pine may hybridize with bishop pine (Pinus muricata), and Monterey pine (Pinus radiata).

In the western foothills of the Sierra Nevada, knobcone pine is often a co-dominant with blue oak (Quercus douglasii).[7]

The species is susceptible to fire, but this melts the cone resin, releasing seeds for regrowth.[4] The species seems to be shade intolerant.[4]

• Coulter pine
• Pinus sabiniana

• Bakker, Elna S. (1971). An island called California. University of California press (1972). ISBN 0-520-02159-2

Wikimedia Commons has media related to Pinus attenuata.

• Jepson Manual treatment
• USDA Plants Profile: Pinus attenuata
• Virginia Tech Dendrology – Knobcone Pine
• Pinus attenuata in the CalPhotos photo database, University of California, Berkeley