PREFACE 



There are already so many books embodying elementary 

 courses in botany that whoever offers another should give 

 reasons for so doing. As here set forth, the study of plants 

 is related to everyday life more closely than is usually done. 

 Those aspects of plant life are presented which have the 

 largest significance to the public in general, and which are 

 of interest and educative value to beginning students. The 

 book includes the principles of plant nutrition, the relation of 

 plant nutrition to soils and climate and to the food of animals 

 and men ; it discusses some of those diseases of plants, ani- 

 mals, and men, which are produced by parasitic plants ; the 

 propagation of plants, plant breeding, forestry, and the main 

 uses of plants and plant products are given in an elementary 

 way. The elements of plant life and structure are presented 

 synthetically rather than by use of the special divisions of 

 botanical study, which are more helpful to advanced students 

 than to beginners. It is believed that this mode of treatment 

 stimulates and develops a scientific method of thinking by 

 directing attention to the plant as a living unit and a citizen 

 of the plant world. No attempt is made to include references 

 to such recent discoveries in the field of botany as are botani- 

 cally significant but not important for elementary instruction. 



Chapters I and II are so arranged that a student may secure 

 a general introductory appreciation of the significance of plant 

 structure and work. It is intended that Chapter I should be 

 used as a means of raising questions concerning the place of 

 plants in nature. Chapter II presents an outline of the five 

 dominant structures of seed plants, and the kind of work that 

 is done by each. It is intended that this chapter shall enable the 

 student to see the plant as a working unit, while the chapters 



iii 



