8 
BULLETIN 50, U. S. DEPARTMENT OF AGRICULTURE. 
ties for water travel during the summer season. But as the streams 
are icebound from early in October until June and only the harbors 
on the south coast are ice-free during the winter, the dog team and 
sled are still the most general and widely used mode of conveyance 
in winter, although horses are being used more and more during this 
season on established lines of travel. 
VEGETATION. 
Mention has been made of the heavy timber growth on the south 
coast, largely of spruce, with some hemlock and areas of poplar on 
some of the alluvial bottoms. In the Susitna Valley there are exten- 
sive belts of poplar, some of which is good saw timber. 
Fig. 1. — Native grass and tundra-sod ice house, St. Michael, Alaska, July 29, 1911. 
Practically all of the interior that comes within our purview as 
possessing agricultural possibilities is timbered, but for the most part 
the growth is small and thin. Spruce is the most prevalent. There 
are belts of balm of Gilead poplar at the lower levels and quaking 
aspen nearer the snow line. Birch groves occupy many of the benches 
and low hills adjacent to the river bottoms. If not destroyed by fire 
and undue waste, there is enough timber in the interior to meet the 
needs of a largely increased population. 
Grasses in great variety are native to Alaska (fig. 1) and are widely 
disseminated, many of them being of large agricultural value for hay 
and silage and for grazing. Wherever the timber is destroyed by fire 
or cut away, grasses at once spring up and make a luxuriant growth. 
Other native vegetation of agricultural economic value includes a 
considerable variety of wild fruit — salmon berries, red and black 
