Thursday, October 7, 2010

Pseudotsuga macrocarpa - Big Cone Spruce

Pseudotsuga macrocarpa: Pseudotsuga, meaning false hemlock -- 'tsuga' is the Japanese name for hemlock; macrocarpa, meaning literally 'big cone'.

There is also an effort to popularize the more accurate common name, Big Cone Douglas Fir.

Growth rate slow to 60' tall and 30' wide, developing a broad conical shape, stout trunk, long horizontally spreading branches, irregular with age, with sparse areas between older drooping branches often sprouting juvenile growth.


Needles are stout, densely set, bluish-green to dark-green, 3/4 to 1" long, slightly curved, whorled along branchlets, appearing 2-ranked or semi-flattened, with a slightly grooved upperside, ends slightly more pointed than P. menziesii, and persisting about 6 years. Slender twigs are reddish brown, slightly hairy at first with shiny dark brown pointed buds, slightly shorter than those of P. menziesii.


Cones are reddish brown, 4-7" long by 2-3" wide, short stalked, narrowly ovate, hanging from branch ends, with shortened tri-tipped, pointed bracts extending just beyond the broad, thick, rounded scales, ripening in summer and opening in fall of the first season, but may persist into the following year.


A closer view of the conescale bracts.


Bark is dark reddish brown, thickening at an early age and becoming roughly furrowed, with wide, heavy ridges and interconnecting narrow cross-ridges.


Evergreen. Native to southern California on dry slopes and in canyons from Kern and Santa Barbara counties south to Baja California at 1,000-7,000' elevation, outside the range of Douglas-fir to the north.

Limited to southern California mountain habitats, along ridgetops and steep ravines, in loose scattered groves. Tolerates drier conditions than Douglas fir, growing in chaparral and mixed conifer regions, with canyon live oak, as well as pinyon, Jeffrey, ponderosa, sugar, and gray pines.

2 comments:

  1. Tightly correlated to mychorrizae associations and shrub communities.

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  2. Just saw this, prety far North from the range described here, just about Redinger Lake, in the San Joaquin basin.

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