develop slowly and are often poorly stocked and patchy. Such stands may 

 develop into fairly well-stocked hemlock-spruce forests but it will 

 probably require a much longer period than for stands on raised beaches. 



A study is in progress to obtain information on growth and yield for ad- 

 justing the existing Southeast Alaska yield tables to Yakutat foreland 

 conditions. 



Forest Management Research in Interior Alaska 



Our 1955 annual report described the broad forest research needs in 

 Alaska's interior forests. Forest management research in the Interior 

 began in the summer of 1957 with a reconnaissance of the more accessible 

 areas. More than one dozen growth and yield plots and several silvi- 

 cultural and silvical plots were established to become more familiar 

 with the types and to provide a basis for the design of specific studies 

 for the next few years and the development of a research program for the 

 future. 



WATERSHED MANAGEMENT STUDIES 



Pulp Logging on Salmon Spawning Streams 



Pulp logging has so far shown no measurable effects on salmon streams. 

 Logging has been in progress since August 1953 on Maybeso Creek, one of 

 five streams in the study of effects of logging on salmon spawning 

 streams. About 60 percent of the merchantable timber was felled and 

 46 percent yarded as of March 1957. 



Mean monthly discharge of Maybeso Creek during the first three years 

 of the transition period from an unlogged to a logged watershed con- 

 dition was almost the same as for the prelogging period. This actually 

 represents a small net increase in discharge because precipitation 

 averaged 10 inches less per season (May through October) during the 

 transition period than during the prelogging period. The discharge of 

 Harris River, an unlogged watershed adjacent to Maybeso Creek, showed 

 the effects of the reduced precipitation amounts. 



The tiny net increase in Maybeso Creek discharge occurs during the 

 period of normal low flow. The effect may be beneficial for silver 

 salmon fry that remain in fresh water for one year before entering salt 

 water. Higher stream stages during the period of normal low flow also 

 might help early spawners to migrate upstream. 



Three years of logging has had no effect on the water temperature of 

 Maybeso Creek. Average annual water temperatures during the transition 

 period are colder by about one degree than those during the prelogging 



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