NOTES ON THE FLORA, ESPECIALLY THE FOREST 
FLORA, OF THE BITTER ROOT MOUNTAINS. 
BY L. H. PAMMEL. 
During the past summer a hasty survey v^as made of 
that part of the Bitter Root mountains v^est and south of 
Hamilton. The range on the whole is not a lofty one, the 
highest peaks being about eleven thousand feet high. The 
mountains are fairly well timbered. There are few lakes 
and comparatively few meadows in the area visited. 
The lower foothills consist of bare slopes with a few 
trees. These consist of scattered groves of Finns pon- 
derosa, common xerophytic plants \\kQ Artemisia tridentata, 
Purshia tridentata, and Achillea millefolium. The benches 
on the west slope of the mountains were once thickly cov- 
ered with Finns 'ponderosa, which has largely been removed 
through the operation of large lumber companies. 
There is a well marked zonal distribution of the several 
conifers found in these mountains. The lower zone is 
occupied by the Finns ponder osa, followed by the Pseudotsuga 
douglasii. This is followed by the Finns mnrrayana. The 
Finns alhicanlis occupies the upper zone of the Lodge Pole 
pine region. Picea engelmannii and Abies snhalpina occur in 
the canons and narrow valleys of the streams extending 
over a considerable altitude, from four thousand feet to 
timber line. 
THE PINUS PONDEROSA ZONE. 
The Yellow pine has admirably adapted itself to all the 
lower, drier slopes; much of this is very rocky. The soil is 
rather thin, but well drained. The young trees are usually 
( 87 ) 
