ocr., 1899.] PLANTS. 137 
Pinus lambertiana Douglas. Sugar Pine. 
Fairly common in most parts of the Transition zone forest of ponderosa 
pines, and oceurring here and there in the immense areas of chaparral 
that cover the lower slopes on the south and west sides of the mountain. 
(See pp. 32-33.) 
Pinus albicaulis Engelmann. White-bark Pine. 
The timberline tree of Shasta, which it encircles at altitudes ranging, 
according to slope, from about 7,000 up to 8,000 feet, and pushing up 
on the warmest ridges to an extreme elevation of 9,800 feet. In its 
distribution therefore it fills the Hudsonian zone except in places 
unsuited to tree growth. The only tree competing with it on Shasta 
is the black alpine hemlock, which, requiring more moisture, is at a 
disadvantage and is confined to special localities, as explained in full 
under that species. (See pp. 39-42.) 
Pinus ponderosa Laws. Ponderosa or Yellow Pine. 
The most abundant and characteristic tree of the lower slopes and 
basal plane of Shasta, where, filling the Transition zone, it forms a con- 
tinuous open forest of wide extent. (See pp. 30-32.) 
Pinus murrayana Balfour. Lodge-pole Pine. 
Confined to the northeast quadrant of Shasta, where it occupies the 
lower part of the Canadian zone. (See pp. 38-39.) 
Pinus attenuata Lemmon. Knobcone Pine. 
Common in a limited area in the Transition zone on the south side of 
Shasta, where it is confined to the lower slopes (from about 4,000 to 
0,600 feet altitude) from Panther Creek easterly to between the 
branches of Mud Creek. (See pp, 33-34.) 
Tsuga mertensiana (Bong.) Carr.’ Black Alpine Hemlock. 
A characteristic tree of the Hudsonian zone, where, however, it is 
not generally distributed for the reason that the upper slopes of Shasta 
are in most places too dry for it. It occurs in the same belt with Pinus 
albicaulis, but does not reach so high, and, requiring more moisture, is 
confined to disconnected localities, usually in canyons and gulches or 
along the shady sides of buttes or ridges. (See pp. 42-40.) 
Pseudotsuga mucronata (Raf.). Sudw. Douglas Fir or Spruce. 
Common, scattered through the less arid parts of the forest of pon 
derosa pines which clothes the lower Transition zone slopes of Shasta 
aud extends away in all directions (see p. 32). A subspecies pendula 
(Engelm.) Sudworth, with ‘“brauches, at least the lower ones, very 
slender and long-pendent,” has been described from Sisson (Bot. Calif., 
II, 483, 1880; Sudworth, Check List Forest Trees of U.S., 24, 1898), 
and is common theuce westerly to the coast. (See pp. 54-35). 
1 For change of name from 7suga pattoni to T. mertensiana, see footnote p. 42. 
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