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 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.
[4] 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.
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.