Flora of Scotts Creek Watershed
Pinus attenuata - Knobcone Pine
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Family Name: Pinaceae
Common Name: Knobcone Pine
Origin: Native to California
Habitat: Closed-cone-pine forests, chaparral, rocky outcrops. Below 6200 ft.
Life Form and Duration: Perennial Tree, generally 6-12 m, tallest 36 m tall. 30-60 cm diameter
Comments on overall growth: Generally multiple trunks, often forms dense stands. Crowns on young trees dense and broad, opening when mature with an irregular branching pattern, may have several tops.
Bark and Stem Description: Gray-brown, with shallow furrows and scaly ridges.
Foliage Type: Evergreen
Foliage Description: Needles, 3 per bundle, persistent sheath at base, 6-16 cm long, yellowish green.
Fruit Type: Seed Cone
Fruit Description: Female cones produced in groups of 3-5 in whorl around branch on almost every year's growth along trunk and major branches. Cones strongly serotinous and remain attached to the tree for several years, closed until heat from a fire melts the resin seal and allows the cone to open and disperse its seeds. Cones may be grown over by stem growth. Cones elongated, asymmetrical, conic and arched in shape, 6-18 cm long, yellow-brown weathering to dull grey. Cone scales with prickles, scales more massive and knobby on upper side of cone near base. Matures in 2 years.
Other Comments: Found at higher elevations in the hills of Swanton. Tends to hybridize with Pinus radiata in the mountains around Santa Cruz area.