228 Trees for Shade and Ornament 
ically ranged under Abies and popularly under Spruce), and Pseudo- 
tsuga, also formerly considered under Adzes and variously called Doug- 
las or Red or Yellow Spruce or Fir, or Oregon Pine. 
If symmetry, formality, stiffness and stateliness are the character- 
istics of firs and spruces, graceful elegance of form, unsymmetrical yet 
regular, pendulousness of branch tips, and softness of foliage character- 
ize the hemlocks, the most beautiful of our conifers. Being of alpine 
or northern origin, the hemlocks prefer a cool, humid atmosphere and 
cool, well-watered, light loamy soils; while they still grow, to be sure, in 
dry soils, they do not thrive in wet ones. They transplant easily (not 
from the woods), but resent changes in their surroundings when once 
adapted. They are free from insects and other troubles, except that 
the Douglas Fir must be selected from those localities of its wide range 
which prevent its succumbing to drought or frost. They are very 
shade-enduring trees, fit for planting singly and in groups as a back- 
ground to flower and especially rock gardens, as undergrowth for taller 
evergreens, or among broad-leaved evergreens like rhododendron, and 
for hedges which are not to be too formal. 
Tsuga. 7. Canadensis Carr. (38), the common Henilock of the north- 
eastern United States, ranging south to Georgia, on the northern 
slopes of mountains. Its very dense, dark green foliage with faint 
white lines on underside is the most pleasing of all conifer foliage, 
both in detail as well as in mass. It is a moderately rapid, but per- 
sistent grower, and free from troubles. It is best planted singly on 
lawns, where at least fifty feet of growing space is available, and in 
groups, also for hedges. Drouthy situations should be avoided. 
T. Caroliniana Engelm. (39), the hemlock of the Carolina Moun- 
tains, is more compact in form and foliage and of lighter hue. It 
seems hardy north to Ontario. 
Of our two western hemlocks, T. Mertenstana Carr. (40), the com- 
mon hemlock of the lower mountain ranges, shows little difference from 
our Eastern species, but 
T. Hookeriana Carr. (41), formerly Pattoniana and Mertensiana, 
the Alpine Hemlock of the Pacific Coast near the timber line, as yet 
little planted, is very distinctive, with a wealth of dense, dark, crowded, 
bluish-green foliage, and quite a picturesque, unique, terraced arrange- 
ment of branches in tiers. The trunk of old trees too is unique, with a 
brown-colored bark in fissures resembling that of the oak. 
Pseudotsuga. P. taxifolia Britt. (42) Gormerly Douglasi), Douglas 
