Knobcone Pine
Encyclopedia
The Knobcone Pine, Pinus attenuata, is a tree
that grows in mild climates on poor soils. It ranges from the mountains of southern Oregon
to Baja California
with the greatest concentration in northern California
and the Oregon-California border.
The leaves
are in fascicles of three, needle-like, yellow-green, twisted, and 9-15 cm long. The cone
s are 8-16 cm long and clustered in whorls of three to six on the branches. The scales end in a short stout prickle. The cones remain closed for many years until a fire opens them and allows reseeding. As a result, the cones may even become embedded in the trunk as the tree grows.
In the western foothills of the Sierra Nevada, Knobcone Pine is often a co-dominant with Blue Oak (Quercus douglasii).
Tree
A tree is a perennial woody plant. It is most often defined as a woody plant that has many secondary branches supported clear of the ground on a single main stem or trunk with clear apical dominance. A minimum height specification at maturity is cited by some authors, varying from 3 m to...
that grows in mild climates on poor soils. It ranges from the mountains of southern Oregon
Oregon
Oregon is a state in the Pacific Northwest region of the United States. It is located on the Pacific coast, with Washington to the north, California to the south, Nevada on the southeast and Idaho to the east. The Columbia and Snake rivers delineate much of Oregon's northern and eastern...
to Baja California
Baja California
Baja California officially Estado Libre y Soberano de Baja California is one of the 31 states which, with the Federal District, comprise the 32 Federal Entities of Mexico. It is both the northernmost and westernmost state of Mexico. Before becoming a state in 1953, the area was known as the North...
with the greatest concentration in northern California
California
California is a state located on the West Coast of the United States. It is by far the most populous U.S. state, and the third-largest by land area...
and the Oregon-California border.
Description
The Knobcone Pine (Pinus attenuata) crown is usually conical with a straight trunk. It reaches heights of 8–24 m (26.2–78.7 ft). however, it can be a shrub on especially poor sites. It prefers dry rocky mountain soils. The bark is smooth, flaky and gray-brown when young, becoming dark gray-red-brown and shallowly furrowed into flat scaly ridges. The twigs are red-brown and often resinous.The leaves
Leaf
A leaf is an organ of a vascular plant, as defined in botanical terms, and in particular in plant morphology. Foliage is a mass noun that refers to leaves as a feature of plants....
are in fascicles of three, needle-like, yellow-green, twisted, and 9-15 cm long. The cone
Conifer cone
A cone is an organ on plants in the division Pinophyta that contains the reproductive structures. The familiar woody cone is the female cone, which produces seeds. The male cones, which produce pollen, are usually herbaceous and much less conspicuous even at full maturity...
s are 8-16 cm long and clustered in whorls of three to six on the branches. The scales end in a short stout prickle. The cones remain closed for many years until a fire opens them and allows reseeding. As a result, the cones may even become embedded in the trunk as the tree grows.
Ecology
The Knobcone Pine (Pinus attenuata) forms nearly pure stands, however it may hybridize with Bishop Pine (Pinus muricata), and Monterey Pine (Pinus radiata) on the coast.In the western foothills of the Sierra Nevada, Knobcone Pine is often a co-dominant with Blue Oak (Quercus douglasii).