BRITISH PLANTS: 



THEIR BIOLOGY AND ECOLOGY 



INTRODUCTION 



THE ENVIRONMENT— FUNDAMENTAL CONSIDERATIONS 



The study of plants in relation to their natural sur- 

 roundings or environment is known as Plant Ecology 

 (Gr. oikos, a home). 



Every plant which lives and succeeds in reproducing 

 itself may be regarded, on the one hand, as an efficient 

 machine, satisfactorily performing its various physio- 

 logical functions ; and, on the other, as an organism adapted 

 to, or in equilibrium with, its environment. Otherwise 

 it would perish and leave no descendants behind. Again, 

 when we examine any association of plants hving together 

 under much the same conditions, a wonderful diversity 

 of form, habit, and growth meets our eyes ; and, seeing 

 that each plant in this association is a successful unit in 

 the battle of life, we are driven to the conclusion that not 

 only is it adapted to its environment, but that this 

 adaptation is reached in many and various ways. 



These three considerations — namely, 



(1) That a successful plant is an efficient machine ; 



(2) That it is in equDibrium with its environment ; 



(3) That this adaptation is reached in many different 



ways 



— lie at the root of Plant Ecology, and form the basis upon 

 which our knowledge of the vegetable population of the 

 globe has been founded. 



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