GENERAL PAPERS 123 
PLANT ECOLOGY AND ITS RELATION TO 
AGRICULTURE 
W. G. WATERMAN, UNIVERSITY OF CHICAGO 
I. CONTENT OF ECOLOGY 
A. Nature and Scope. In beginning this discussion, a 
brief statement as to the nature and scope of ecology seems 
to be desirable on account of the hazy popular notions on the 
subject. Outside of a rather narrow circle one usually finds a 
total ignorance of the meaning of the word itself, and even 
among biologists, some are familiar only with the observation- 
al side, due probably to the early prominence of the “car 
window” school of ecologists, while others consider that the 
subject matter of ecology might better be divided between 
morphology and physiology, and frankly state their opinion 
that there is no such subject as ecology. 
However, there seems to be a mass of subject matter belong~ 
ing to neither department exclusively, but partly to each, 
which would fairly warrant the formation of another depart- 
ment. This has been named ecology, and may be defined as 
the science of the forms of organisms as affected by the 
factors of their environment. The connection with physiology 
is the closer of the two, and in fact, the two subjects overlap to 
a certain extent, but whether we call this overlapping segment 
ecological physiology or physiological ecology, the character 
of this subject matter is sufficiently different to warrant a 
separate category and different treatment. 
The methods of ecology have been, of course, largely de- 
scriptive, but they are also becoming increasingly quantitative, 
employing in many cases elaborate and delicate instruments, 
The work is pursued both in the field and in the laboratory, 
and under experimentally controlled conditions, as well as 
under natural, The great task of ecology and the purpose of 
its observation and experimentation lies in the interpretation 
of the phenomena and the deduction from these data of the 
general principles underlying the reaction of plants to their 
environmental factors. 
B. Content of General Ecology. 
