Some mortality is occurring and if this is coupled with several years of nil or 

 light seed crops the result could be less than full stocking. The threat of a 

 catastrophic reduction in seedling numbers by such agencies as fire, small 

 mammals, or insects, makes it desirable that clear cuttings are of a size that 

 can regenerate naturally from local seed sources until full stocking is assured. 

 Present recommendations are that no part of a clear cutting should be more 

 than 20 chains from an effective seed source. 



^ Seed Production in an Unmerchantable Stand. --A study of seed production 

 in a stand with timber volumes below present limits of merchantability was 

 summarized in the biennial report for 1957-58. Since then, the details were 

 published as Technical Note No, 43, "Seed production in a scrub stand." 



This exploratory study indicates that large quantities of seed are produced by 

 scrub trees, particularly western redcedar. The production of about 46 pounds 

 of seed per acre of all species during a light to medium seed year compares 

 favorably with the production of 91 pounds obtained in another study in a climax 

 stand during a "bumper" year. 



Scrub stands will be increasingly important seed sources as pulp logging in- 

 creases. Such stands often border commercial stands. Thus they are seeding 

 in parts of many cutover areas. The genetic desirability of scrub stands as 

 seed sources is a problem in need of study. 



^ R egional Cone Crop Ratings . --A system developed by the Oregon State 

 Board of Forestry for rating cone crops was adopted in the Alaska region. The 

 system is used in a long term study designed to establish seed crop periodicity 

 and the relationships between size of seed crop and such factors as weather. 



Technical Note No. 50 "1959 cone crop report for Alaska tree species", des- 

 cribes the rating system and summarizes the reports for the 1959 season. 

 Many years of records will be needed before conclusions can be developed. 

 Cone crop ratings for the first three seasons are summarized in table 2. 



^ Other seed studies are in progress to determine seed production in white 

 spruce and paper birch stands and to determine the character and amount of 

 seed crop losses to squirrels and to insects. 



Estimiating Site Index in Sapling and Pole Stands . --The usefulness of con- 



ventional height-over -age curves for estimating site index in Southeast Alaska 

 is limited to stands older than 30 or 40 years. For younger stands a method 



15 



