during a period of low relative humidity and consequent high inflam- 
mability of the timber and duff. 
The data for snowfall are even more meager than for rain- 
fall. On the lowlands of the Palouse region at Moscow there is a 
mean annual snowfall of approximately fifty inches. At the station 
of Murray within the mountains at 3000 feet, an average depth of 
twelve feet or more has been recorded. At Burke, 4082 feet in eleva- 
tion, the average recorded for a period of nine years is over seven- 
teen feet (207 inches). On the high ridges and slopes no data are 
available, but judging from the position of traps, blazes, and other 
indirect evidence, the average probably exceeds seventeen feet. At 
Port Hill in the Kootenai Valley near the Canadian Boundary, with 
an elevation of 1615 feet, the average depth recorded is seventy-six 
inches or more. At all of these stations the greater part of the snow- 
fall is recorded from November until March. In the mountains at high 
elevations, snow during the summer months is infrequent and ephemeral. 
Generally speaking, at lower elevations the first killing frost seus 
from the first week in September to the first week in October; the 
last, during May. Few or no data are available for higher elevations. 
The range of temperatures approaches the continental type. 
The minima recorded occur from Janvary to March and vary during this 
period according to position from north to south and to a less degree 
with elevation. At Moscow the absolute minima recorded vary from -1° 
to -27° F.; at Port Hill, from -8° to -28° F.; at Murray, from -6° to 
~22° F. Lower minima doubtless occur at higher elevations. The abso- 
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