North American Forest Research: Investigative Projects in Forestry and Allied Subjects, Conducted by National, State, and Provincial Governments, Schools of Forestry, Scientific Schools, and Private Interests in Canada, Newfoundland, and the United States for 1919-1920

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National research council of the National academy of sciences, 1920 - Всего страниц: 300

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Стр. 151 - Number 4. North American forest research. Compiled by the Committee on American Forest Research, Society of American Foresters. August, 1920. Pages 146. Price $2.00.
Стр. 270 - ADAMS, CHARLES C, HANKINSON, TL, and KENDALL, WC 1919. A Preliminary Report on a Fish Cultural Policy for the Palisades Interstate Park.
Стр. 183 - To determine the best methods of cutting in different forest types to secure natural reproduction in the shortest possible time.
Стр. 166 - The Reproduction of Commercial Species in the Southern Coastal Forest of British Columbia
Стр. 237 - ... plants and in some cases are undertaking the eradication of their own accord. Farmers' Bulletin 826 presents the methods of eradication and results secured.
Стр. 250 - ... Long Island, NY, against the hickory barkbeetle in the hickories and the two-lined chestnut borer in the oaks, which was completed during the fall of 1916, apparently has resulted in a great reduction in the numbers of these two insects, which were a menace to the hickories and oaks of the island. The oak shade and forest trees of the Southern States have suffered severely from the attack of the Romaleum oak borer in the main trunks and the Prionus root borer in the roots. Special investigations...
Стр. 199 - Such tests form a basis for the comparison of species, the choice of species for particular uses, and for the establishment of correct working stresses.
Стр. 174 - Incidental Results of a Study of Douglas Fir Seed in the Pacific Northwest,
Стр. 249 - ... be a menace to the standing pine, spruce, and Douglas fir timbers of the Rocky Mountains and Pacific slope wherever control measures have not been adopted and carried out to prevent the spread of local outbreaks, and in the aggregate many millions of dollars' worth of the best timber has been lost. Wherever the methods that have been determined and advised by this bureau have been adopted and carried out, most gratifying results have followed. Especially is this the case in and adjacent to areas...
Стр. 250 - Results. — It has been determined that some of the flat-headed borers are primarily destructive to living trees, while others contribute to the death of weakened trees or are destructive to the wood of living and dead timber, and that a large percentage of the losses can be prevented through a practical application of the information already acquired and published. Special progress has been made in the investigation of seasonal histories and habits of many species of flat-headed borers and methods...

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