SHADE TREES. 



137 



idal type of crown are better suited for narrow avenues. In considering 

 the problem of the selection of shade trees it should be borne in mind 

 that there exists much variation in their habit of growth due to the con- 

 ditions under which they are grown, and what may do well in one loca- 

 tion will be more or less of a failure in another. There exists a marked 

 variation in the growth of trees, even of the same species, in a restricted 

 territory, and one can find much variation in their mode of development, 

 such as habit of branching, size and color of leaves, height to wliich the}'' 

 grow, and age to which they attain, — in short, their general configura- 

 tion. The elm grows quite differentlj' in the north than in the south, 

 and even in New England manj'^ specific types may be met which are 

 characteristic of special localities. Hence, in order to secure the best 

 type of elm trees for planting it would be well worth while to obtain 

 them from localities which develop the best branching habits, such, for 

 example, as the Berkshire region in Massachusetts. There are some 

 species that are indigenous to the south which grow larger and do better 

 in their native environment than in the north. 



Such trees as the magnolia, catalpa, Kentucky coffee tree, box elder, 

 persimmon and mock orange are much better adapted to the south than 

 the north, and consequently are of much more value as ornamental trees 

 in that section. 



What shall we plant? 



Perhaps the most perplexing question relating to shade trees, at least 

 during the last decade, is ''What shall we plant?" There has probably 

 never been a period within the momorv of living man during which such 

 severe conditions for 

 vegetation have pre- 

 vailed, especially in 

 the eastern States, as 

 in the past few j^ears. 

 Meteorological rec- 

 ords for many years 

 back would undoubt- 

 edly fail to show 

 similar conditions, 

 and even if they did 

 they would be of 

 little value, owing to 

 the fact that there 

 are important factors 

 other than those re- 

 corded by meteoro- 

 logical observations which greatlj^ affect vegetation and its mode of 

 development. The growth of trees themselves, as well as local variations 

 in a restricted environment, constitute a record of general meteorological 

 phenomena. Since trees live a century or more, these data are valuable. 



Fig. 9. — Showint 



deterioration of elms, largely due to the 

 leopard moth. 



