24 BULLETIN 327, U. S. DEPARTMENT OF AGEICULTUEE. 
even-aged stands when the latter are more or less suppressed. Domi- 
nant trees 6 inches in diameter in an open stand are about 30 years 
old, while dominant trees of this size grown in a dense stand are from 
about 40 to 120 years old. Trees 16 inches in diameter that have 
grown in an open forest are about 130 years old, while dominant 
trees 12 inches in diameter grown in a close stand are about 156 years 
old. Suppressed trees 6 inches in diameter may be from about 50 to 75 
years old, according to the density of overhead shade. In excep- 
tional cases wholly suppressed trees 2 to 3 inches in diameter may 
be from 75 to 100 years. 
ALPINE FIE. 
Abies lasiocarpa (Hook.) Nuttall. 
COMMON NAME AND EARLY HISTOEY. 
Alpine fir is one of the smallest of the western firs and perhaps 
also one of the least known there, owing to the fact that it grows 
chiefly at high altitudes. The common name, " alpine fir," adopted 
here, would seem to be the most appropriate one for this species, 
because it refers to the tree's high mountain habitat. 1 Woodsmen 
and settlers usually call it " balsam " or " mountain balsam." 
It is probable that alpine fir was first discovered in September, 
1805, by Lewis and Clark, while crossing the Bitter Eoot Moun- 
tains (whether on the Montana or Idaho side is unknown), for 
the narrative 2 of their exploration of our Northwest mentions " a 
growth of eight different species of pine," which by exclusion must 
have included this fir. 3 To David Douglas belongs the credit of 
having first collected a specimen of this fir in 1832 in the " interior 
of N. W. America." On this specimen is based the first published 
technical description and name of the tree, " Pinus (Abies) lasio- 
carpa Hooker," published in 1839, and on which the present name, 
Abies lasiocarpa (Hooker) Nuttall, is founded. Dr. C. C. Parry 4 
seems to have been the first to find alpine fir in our central Rockies 
(Colorado), where he observed it in 1862, and from which in 1863 
he distributed seed. 5 It was not known, however, until 1876 that the 
1 Abies lasiocarpa is frequently called " balsam fir," probably because of its general 
resemblance to tbe true balsam fir (Abies balsamea), to wbicb, however, tbis name prop- 
erly belongs, having been applied to it long before tbe alpine fir was known to botanists. 
2 History of tbe Expedition under Command of Lewis and Clark, 1804-1806 (ed. Dr. 
Elliott Coues), II, 598. 
3 It was common in the early days, even for botanists, to designate as " pine " tbe trees 
we now know as firs. 
4 Engelmann in Am. Nat, 555, 1876. 
5 There appears to be no record of plants raised from this seed. Probably the first 
trees known in cultivation were grown from seed planted in 1873 in the Arnold Arbore- 
tum, Massachusetts. Their growth in height for the last 40 years has, however, been 
excedingly slow, amounting to only about 3 or 4 inches per year. Alpine fir seems to 
have been introduced into England in about 1890, but according to Elwes and Henry 
(Trees of Great Britain and Ireland, IV, 803, 1909) its growth there has been practically 
a failure. The German Government imported seed of this fir for forest experiments in 
the early nineties, and these trials show the tree to be better adapted to the climate of 
Germany than to that of England. 
