344 EXPEBIMEKT STATTON RECORD. 



the results of investigations begun during the season of 1909 and continued in 

 1911 with the object of determining the part of the tree in which cambium 

 activity begins, as well as to determine the season of growth. 



From observations made during the 2 se-asons and from the results of other 

 investigators, the author is inclined to the opinion that in general diameter 

 growth does not begin until the leaves have been fully developed and have 

 become sufficiently active in food making to supply the requirements of rapid 

 cell formation. The results thus far secured are considered insufficient to estab- 

 lish the reg'ion of the tree in which cambium activity first begins. 



Studies on tlie anatomical structure of woods of Japanese conifers, M. 

 FuJiOKA {Jour. Col. Agr. Imp. Univ. Tokyo, ^ {1913), No. 4, pp. 201-236, pis. 

 7). — The various species studied are described with reference to their macro- 

 scopic and microscopic wood structure and they are fully illustrated by a photo- 

 graphic series of cross, tangential, and radial wood sections. A bibliography 

 of literature on wood structure is also given. 



Experiments in the preservative treatment of red-oak and hard-maple 

 crossties, F. M. Bond {U. 8. Dept. Agr., Forest Serv. Bui. 126, pp. V2, pis. 9. 

 figs. 26). — The experiments here described were conducted by the Forest Service 

 in cooperation with the University of Wisconsin and the Chicago, Milwaukee, 

 and St. Paul Railway. 



Fart 1 of the bulletin describes the treatment of the ties and discusses the 

 data of immediate value obtained during the application of the preservatives. 

 Part 2 contains a description of the test track and tabulated records essential 

 for an analysis of the durability data which will be obtained in future inspec- 

 tions. The preservative processes employed included at least one from each 

 general type of pressure process in common use. Treatments were begun in 

 October. 1910, and completed in May, 1911. The track was laid in August. 1911. 



The following are among the general conclusions derived from the preserva- 

 tive treatments: Under the same conditions of treatment a given absorption 

 per cubic foot of wood was obtained in a shorter time in hard-maple than in 

 red-oak ties. For a given treatment there is a greater variation of absorption 

 between individual ties of hard maple than those of red oak. Variations in red- 

 oak ties tended toward an excessively high rather than an excessively low 

 absorption. The penetration of preservative in hard-maple ties was largely in 

 the sapwood and in the seasoning checks and was very erratic in the heiirtwood. 

 In red-oak ties there appeared to be no relation between the absorption of pre- 

 servative per cubic foot and the proportion of sapwood in the ties, the amount 

 of absorption being in inverse proportion to the moisture content and oven-dry 

 weight. Absoi-ption was also slightly greater as the average number of annual 

 rings per inch increased. The absorption of preservative per cubic foot of wood 

 in hard-maple ties having nearly equal proportions of sapwood increased as the 

 oven-dry weight per cubic foot decreased. The oven-dry weight per cubic foot 

 of red-oak ties increased as the average number of annual rings per inch de- 

 creased. The rate of loss in weight after treatment was greater for red-oak 

 than for hard-maple ties treated in a similar manner with creosote only or with 

 the gas-house oil used in these experiments, but the rate of loss was much 

 greater for hard-maple than for red-oak ties treated in a simliar manner with 

 aqueous solutions of zinc chlorid. 



Considerable data are appended dealing with accuracy of the various deter- 

 minations, errors in measurements by float gauges, and analyses of preservatives. 



Forest products of Canada, 1912. — Pulp wood, R. G. Lewis and W. G. H. 

 BoYCE {Dept. Int. Canada, Forestry Branch Bui. 38, WIS, pp. 20, figs. 4). — As in 

 similar reports (E. S. R., 27, p. 443) a statistical account is given of the quantity 

 and value of the pulp wood produced in the Dominion according to the Provinces 



