34 BULLETIN 327, V. S. DEPARTMENT OF AGRICULTURE. 
Abies concolor (Gord.) Parry is technically based. Botanists have 
generally maintained this name, although since its establishment 
some fifteen other specific and varietal names (now made synonyms 
of A. concolor) have been published. These names were created 
chiefly, however, either through confusion of the white fir with other 
Xorth American firs, or through imperfect knowledge of the variable 
forms of the tree peculiar to different parts of its extensive range. 1 
One of the best marked varietal forms of white fir well known in 
cultivation is Abies concolor lowiana (Murr.) Lemmon. It has short 
pale green foliage and occurs in the California Sierras and in the 
Siskiyou Mountains of southern Oregon. European dendrologists 
have segregated five other cultivated varieties, chiefly by the color of 
their foliage, shape of the leaves, and habit of the crown or of its 
branches. The characters relied upon to distinguish these latter 
garden forms do not, however, appear to be sufficiently dependable 
to warrant maintaining the plants as distinct varieties. 
DISTINGUISHING CHABACTEEISTICS. 
White fir grows to its largest size in the Pacific region, where it is 
frequently from 140 to 180 feet, and occasionally over 200 feet, high, 
with a diameter of from 40 to 60 inches, rare trees being from 5 to 6 
feet through. In its Eocky Mountain range, however, white fir is a 
much smaller tree, at best being only from 80 to 100 feet in height, or 
rarely more, and from 20 to 30 inches in diameter. The massive 
trunks have conspicuously rough ash-gray bark, which is broken into 
great, deep, wide furrows and ridges. The bark is very hard and 
horny and from 4 to 6^ inches thick on the largest trunks (PI. 
XXIV). Bark of the upper stems of large trees and on young trees 
is smooth and unbroken and grayish, with a slight brownish tinge. 
The trunks are straight and taper very gradually. The dense crown 
of heavily f oliaged short branches is an irregular, round-topped cone, 
extending to the ground on trees in open stands, while in dense stands 
the crown covers only one-third or one-half of the stem. Young trees 
have beautifully symmetrical, sharp crowns extending down to the 
x According to Elwes and Henry (Trees of Great Britain and Ireland, IV. 780, 1909), 
the California form of white fir was first introduced into England in 1S51, while the 
Rocky Mountain form of this species was introduced there in about 1S72. Trees raised 
from California seed are said to grow more thriftily in England than stock from Rocky 
Mountain seed. One tree in Oxfordshire attained a height of 71 feet and a diameter of 
about 2 feet in 28 years. The largest trees growing in England are from about 70 to 90 
feet in height and from 20 to 40 inches in diameter. The German Government purchased 
considerable quantities of white fir seed, both of the Rocky Mountain and Pacific slope 
forms, in the early nineties for experimental forest planting in Germany, but the results 
of these trials are unknown to the writer at present. Doubtless the Rocky Mountain 
form has proved more adaptive to German conditions, judging from the excellent growth 
of Douglas fir from this region and the failure there of Douglas fir plants raised from 
Pacific slope seed. White fir from the Rockies and the Pacific slope grows thriftily in 
eastern United States but stock from the interior mountains is far better adapted to this 
region than the more western form, while for ornamental planting the Rocky Mountain 
trees are much handsomer in form and in bluish-tinged foliage. 
