Sherwin Carlquist 
Comparative Wood Anatomy [PDF ebook] 
Systematic, Ecological, and Evolutionary Aspects of Dicotyledon Wood

Diagnostically illustrated with light and scanning electron micrographs, Comparative Wood Anatomy lucidly introduces dicotyledon wood in terms of cell types and their variations, pertinent literature, taxonomic distribution of features, terminology, and methods for preparation. Two final chapters present syntheses: taxonomic achievements of wood studies; and the evolutionary relationship between structure, physiological function, and ecology. This detailed survey serves a wide range of interests: identification, systematics, evolution and physiology.