38 BULLETIN 327, U. S. DEPARTMENT OF AGEICULTUEE. 
the abundant supply of cones the squirrels " cut down." During 
light or poor seed years this consumption may in some localities well 
include practically the entire crop, but in seasons of heavy seed pro- 
duction, the loss from rodents must still allow abundant reproduc- 
tion. 
LONGEVITY. 
In general white fir grows rapidly in height and diameter for the 
first 50 to 100 years, after which it grows slowly up to about 350 
years, which is believed to be near its maximum age. The age limit 
of white fir in the Eocky Mountain region is not fully known at 
present, but very probably the largest trees are not over 250 or 275 
years old. 
SHASTA RED FIR. 
Abies magnified shastensis Lemmon. 
COilMON NAME AND EARLY HISTOBY. 
The Shasta red fir has only a very limited range in the Rocky 
Mountain region (Map Xo. 10; western edge of Xevada), its princi- 
pal range lying in the Pacific slope region. 
From the forester's point of view Abies magnifica and its variety, 
A. magnifica shastensis, which is distinguished from the former by its 
shorter and thicker cones and by the exserted bract of its cone scales 
(PL XXV, a), are practically one tree. Indeed, without seeing the 
mature cones of the species and its variety, it is impossible to dis- 
tinguish one tree from the other. Their silvical habits and habitat 
are essentially the same. 
The common name, Shasta red fir, derived partly from the techni- 
cal name, is probably not used by woodsmen and other laymen who 
generally call the species and variety "red fir." The name Shasta 
red fir refers appropriately to the deep red-brown bark which both 
the species and its variety invariably have throughout their range, 
and to the historical fact that the tree was originally found on Mount 
Shasta, Cal. 
Abies magnifica was first discovered in 1815 by Col. Fremont 
on his expedition to California, the first authentic description of it 
appearing in 1863. The Shasta red fir was found first on Mount 
Shasta, Cal., in 1852 by the intrepid Scotch explorer John Jeffrey. 
The earliest technical name given to this form is probably " Abies 
nobilis rubusta" of Carriere, published in 1867; but it is impossible 
to be sure now that Carriere's accompanying description applies to 
the Shasta fir, which in 1890 was properly distinguished for the 
first time as " Abies magnifica var. shastensis " by Dr. J. G. Lemmon. 
