PREFACE 



The rapid development of our country during the last few 

 years has brought about a more general recognition of the great 

 importance of the basic industry of plant production and of 

 the necessity of applying the scientific method to this industry. 

 This recognition emphasizes the importance of the study of the 

 laws of plant growth, whether under the name of botany or of 

 agriculture. 



In presenting this manual it is the intention to place before 

 high-school pupils a series of problems which have to clo with 

 the activities of plants and with their relations to human interests. 



The problem method of presentation has been used. The 

 experience of the best teachers shows that the interest of pupils 

 is better maintained when, so far as practicable, each labora- 

 tory exercise is presented as a definite problem, the solution of 

 which must be achieved by the pupil with only such assistance 

 as will enable him to apprehend the problem and secure the 

 necessary data. Furthermore, the experiences to which it is ex- 

 pected that the pupils will apply their scientific training present 

 themselves as discrete problems, and it is therefore highly desir- 

 able, educationally, that their school work should tend to pro- 

 duce in them the habit of solving environmental problems in a 

 scientific manner. At the same time it is recognized that there 

 are some topics in botany as in any other science that do not 

 lend themselves readily to statement in the form of problems. 

 The author has not hesitated to depart from the problem method 

 of attack in the case of individual exercises when another form 

 appeared desirable. 



The manual is organized about the activities of plants rather 

 than about their structures. The leading exercises are concerned 



