62 JOURNAL OF FORESTRY 



the water requirements of the standard plants are largely a matter of 

 evaporation and temperature. Hence agricultural and forest plants 

 grown in the localities of least rainfall, highest evaporation, and highest 

 temperature should be confined to soils of high water-holding capacity 

 and subject to minimum run-off, so that the soil may provide them a 

 high percentage of the rainfall. 



Evaporation appeared to be the chief factor in limiting the growth 

 and development of plants in the oak-brush and spruce-fir types. Con- 

 sequently, the extension of agriculture and forestry in these associa- 

 tions should be limited to lands protected from excessive evaporation. 

 This can be done by selecting sites more or less protected by native 

 vegetation and natural obstacles. The opinion is expressed that failures 

 from forest planting in the middle or aspen-fir type are seldom caused 

 bv adverse climatic conditions, but by preventable causes. Although 

 the bulletin contains a fund of information for students of site factors 

 and their correlation with the resulting vegetation, it brings us no 

 nearer to an acceptable method of relating forest vegetation to the 

 complex of physical factors which constitute the environment. 



J. W. T. 



The Preservation of Wood. By A. J. Wallis-Tayler. Wm. Rider 

 & Son, Ltd., London, ipi/C?). Pp. 344. 



As is so commonly the case with books of this class published in 

 Great Britain, this book is not dated. It may therefore be sold for an 

 indefinite period as the latest work on the subject of wood preservation. 

 Mr. A. J. Wallis-Tayler, who has written similar books on subjects 

 ranging from Diesel engines to tea factories, delivered a paper on the 

 preservation of wood, before the Royal Society of Arts, on the i8th of 

 February, 1914. According to the author's preface, this book is based 

 upon that paper. This is at the outset rather unfortunate, as at that 

 time Air. Wallis-Tayler labored under the impression that the decay 

 of wood begins with the fermentation of the sap, caused by bacteria. 

 In this book we consequently note that "putrefactive fermentation and 

 the subsequent decomposition of vegetable matter is due to albumen," 

 and also that "the most common causes of decay of wood are the pres- 

 ence of sap and being subjected to alternating conditions of wetness 

 and dryness, or to a combination of moisture, heat, and the absence of 

 ventilation," which should be rather instructive information to foresters 

 and others who are working in the field of forest pathology. Decay is 

 classified as "tvct rot and dry or sap rot," and the chapter on this sub- 



