96 TREES IN WINTER 



CHAPTER V 

 THE SELECTION OF TREES FOR SPECIAL PURPOSES. 



As has been shown in previous chapters, there are many factors 

 that determine the choice of species. The fundamental question 

 to be decided is whether a particular type of tree is suited to the 

 purpose from the esthetic standpoint. Usually the choice of species 

 for the production of a given effect is subject to a wide range. Af- 

 ter considering all of the forms that seem to answer the purpose 

 in an ornamental way, it is wtII in the final selection to choose those 

 having few objectionable features. 



Some species are better adapted to a certain set of conditions 

 than others, and certain conditions beyond our control often restrict 

 the selection of species to a very narrow range. Some trees wdll not 

 grow on dry soil, others fail to thrive on wet soil. Some fail to 

 develop properly unless there is an abundance of lime in the soil, 

 and others fail on calcarous soils. Some cannot stand the smoke 

 and gas common to city streets. Some require plenty of sun while 

 others, to reach their highest degree of perfection, must be some- 

 what protected from the hot rays of the sun. Some w^ill not stand 

 the seashore climate and others will fail at high altitudes. 



The relative susceptibility of species to insect and fungus attack 

 is a subject too often overlooked. Certain species, like the White 

 or American Elm, are well adapted to ornamental planting, for 

 both city and country, but cannot be recommended except for 

 places w^here they are likely to be taken care of. And again there 

 are some species that have many desirable qualities and yet are ob- 

 jectionable in one or more respects. The Horse-chestnut, for 

 example, is an attractive and eifective shade tree, but it is objec- 

 tionable on account of the litter it produces on the ground. The 

 Silver Maple is attractive, graceful, and quick-growing, but it is 

 short-lived and easily broken by wind and ice. The sex of trees is 

 an important consideration in some cases. For example, the 

 pistilate or female Carolina Poplar is very objectionale on account 

 of its cottony seeds that literally fill the surrounding atmosphere and 

 attach themselves to buildings, to other trees, and to people's cloth- 

 ing. The male trees of the Ailanthus, also, are exceedingly objec- 

 tionable on account of the odor produced by the staminate flowers. 



