PREFACE 



The aim of this dictionary is to fill the need for defini- 

 tions of many new terms that have come into usage during 

 the past thirty years and also to include many of the old 

 terms that are used in current literature. It has not seemed 

 desirable to include many words that are rarely if at all 

 used at present and which are in the older glossaries. Many 

 words from fields closely related to ecology such as forestry, 

 range management, agronomy, soils, and genetics are in- 

 cluded because of their wide usage in ecological literature. 



The definitions are usually those that are in accord with 

 present general usage. It has not seemed wise to attempt to 

 pronounce judgment on the desirability of, or the need for, 

 certain terms since such decisions are made by usage as a 

 language grows. The inclusion of certain words in this dic- 

 tionary does not necessarily imply that the author approves 

 or recommends their use. 



Words are tools of thought. Clarification of the meaning 

 of terms, precision in their use, and uniformity in usage 

 among workers in ecology and related fields are essential 

 in the growth of a science. When a concept or process can 

 be expressed precisely in ordinary language it appears un- 

 necessary, and indeed detrimental to the growth of a science, 



