4 BULLETIN 1495, U. S. DEPARTMENT OF AGRICULTURE 
DIFFERENCES BETWEEN TYPES 
To serve as a background for the later analysis of fires, a sketch 
of the important differences between cover types in climatic factors, 
fuels, and behavior of fires is needed. These physical differences, 
ELEVATION 
IN FEET F 
MOUNT SHASTA 
14,000 
BARREN 
10,000;— (ABOVE TIMBER LINE) 
8,000— ALPINE 
FIR (SHASTA) 
WOODLAND |GRASSLAND 
10 20 30 40 sO 60 70 80 
DISTANCE iN MILES 
FiGURE 1.—Typical cover-type distribution 2 the northern group of forests, Shasta National 
orest 
particularly the composition of the commercial timber stands and 
forage types, have already played an important part in the formula- 
tion of timber and range management plans in the national forests, 
ELEVATION 
IN FEET : 
MOUNT LASSEN 
10,000 
WEST EAST 
—<—___—_— => 
8,000 
YELLOW PINE= 
é WHITE FIR 
6,000 
YELLOW PINE w 
4,000 aN pine-|2) = 
WHITE = ~ 
YELLOW PINE] FIR |o] 
ALPINE [eee noe AND 4 
WHITE FIR] |JEFFREY PINE 4] @ 
BRUSH BRUSH| | x 
30 sO 60 790 60 
40 
DISTANCE IN MILES 
FIGURE 2.—Typical cover-type distribution in the east-side group of forests, Lassen National Forest 
and foresters have recognized that a fuller understanding of our type 
is needed as the basis for silvicultural practice and range use. The 
bare outline here possible points to the great variation within the 
region, and indicates the complexity of the fire problem and the 
