THE SCOPE OF DENDROLOGY— SOME CORREC- 

 TIONS. 



By H. de Forest. 



A careful consideration of my paper on "The Scope of Den- 

 drology in Forest Botany" appearing in the June number of the 

 Quarterly will not support the conclusion of Dr. Howe that I 

 hold the subject of silvics to be a study of associations of trees 

 alone. The paper states definitely that I consider silvics to 

 cover all ecological investigations' of forests, that such investiga- 

 tion is pursued by means of plant-geography and plant-ecology, 

 one part of the latter dealing with the ecological significance of 

 the morphological and physiological characteristics of the plants 

 of a locality, (the part Dr. Howe says I exclude from silvics), 

 and the other part dealing with the local minutiae of vegetation. 



Dendrology, I believe, deals with facts concerning the indi- 

 vidual tree species that go to make up the forest. Dr. Howe in 

 his appended comment says that this ''would include the study of 

 the biological relationships of single trees." It is undoubtedly 

 and obviously true that the facts mentioned are deduced from 

 the study of the biologic relationships of trees. It is not, how- 

 ever, necessarily true that dendrology itself should include this 

 study. In systematic dendrology, for example, students learn 

 certain facts, certain "ear marks" of tree species Dr. Howe calls 

 them, in order to be able to identify species, but they do not in 

 that subject go into the problems of how and why these "ear 

 marks" occur. The latter is recognized as belonging to another 

 part of botany. The case between dendrology and silvics is 

 somewhat similar. Dendrology has arisen in response to needs. 

 The need so far as biologic dendrology is concerned may be 

 stated as the necessity in educating foresters for giving to them 

 early in their course of training a systematized collection of facts 

 concerning the chief biologic characteristics of important species. 

 It is especially needful in forestry education to learn what may be 

 termed metaphorically the numbers and numeration of the subject 



