Shade Trees, Their Beauty and Importance 



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HE sanitary value of trees is 

 now very generally recognized. 

 In the past this most important 

 factor in the conservation of a healthful 

 and temperate climate was sacrificed 

 with ruthless hand. Through the waste 

 of the forests winters have become 

 colder, summers hotter ; living springs 

 have ceased to flow perpetually ; fertil- 

 izing streams have disappeared ; the 

 earth is deeply frozen in winter and 

 parched in summer, and finally new and 

 grave diseases have appeared where for- 

 merly they were unknown." 



The foregoing is an extract from an 

 article written by Stephen Smith, M.D., 

 LL.D., in 1899, while endeavoring to 

 secure legislation empowering and re- 

 quiring the Department of Parks in New 

 York City to plant and cultivate trees, 

 shrubs, plants, and vines in the streets, 

 avenues, and public places of that city. 

 Other cities in the States have followed 

 suit, and since then a very general re- 

 cognition has been given to the beauty, 

 grace, comfort, and healthfulness of 

 trees, and especially of shade trees in 

 parks and on city streets. 



After our last summer's experience 

 one may well ask, can the temperature 

 of the city during the summer months 

 be modified so as to prevent that ex- 

 treme degree of heat from which one 

 and all suffered, and on which the enor- 

 mous sickness and death-rate of the 

 people depend? Vegetation plays an 

 important part, but especially do trees, 

 in modifying the climate of large areas 

 — the temperature of even a clump of 

 trees is cooler in summer and warmer in 

 winter than the surrounding country. 

 The thermometer will vary from twenty 

 to thirty degrees in the sun and shade, 

 and as much as ten to eleven in the soil, 

 and the reverse is true in winter. Rail- 

 road engineers use far less fuel in pass- 

 ing through forests in winter than in 

 traversing the same distance in open 

 country. Who has not given a sigh of 

 relief when on a hot summer's day he 

 has passed under a tree's friendly shade? 



We have not only shade to be grate- 

 ful for — trees give off a large quantity 

 of water from the surface of their foli- 

 age. The greater amount of leaf sur- 

 face, therefore, the greater amount of 

 vapor emitted. It has been estimated 

 that an acre of grass emits six thousand 

 four hundred quarts of water in twenty- 

 four hours, and that the Washington 

 Elm at Cambridge, Mass., a tree of 

 moderate size, produced a crop of seven 

 million leaves, exposing a surface of 

 five acres of foliage. Thus vegetation 

 tends powerfully to cool the atmosphere, 

 and this effect increases in proportion to 

 the increase in temperature. Carbon 



M. E. T., Toronto, Out. 



is the great nutritive agent the tree 

 needs, and this it gets from the air in 

 the form of carbonic acid gas. In the 

 process of assimilation oxygen is re- 

 stored to the air. Man needs oxygen. 

 Carbonic acid gas is a waste product 

 of the animal system. Thus trees purify 

 the air and the vegetable kingdom pro- 

 vides conditions by which the animal 

 kingdom maintains life and health. 



The tree is a great factor in the mak- 

 ing of a beautiful city. Well chosen 

 specimens — and these well kept and 

 aesthetically planned — will prove of econ- 

 omic value. The beautiful city attracts 

 visitors, and many visitors mean greater 

 business activity, and this leads to the 

 city's rapid growth and prosperity. 



In the choice of trees for street plant- 

 ing several things are necessary and 

 should be considered. Trees must he 

 able to endure hardship and be among 

 those most immune from insect attack. 



Other qualities, too, such as straight- 

 ness and symmetry, cleanliness and 

 longevity, and abundance of shade are 

 desirable. The initial cost of planting 

 such trees is small, but after a number 

 of years who will estimate their value? 

 One species on a street, has given to 

 many cities in the United States a grand 

 effect. The welcome shade, too, is bet- 

 ter secured by the uniform spacing of 

 one species. 



When new planting is being done it 

 would be well to alternate trees of rapid 

 growth with those which grow more 

 slowly. This secures shade and beauty 

 during the time such slow growing 

 trees, as for instance the elms, take to 

 reach maturity. After considering the 

 nature of the soil, the width of street, 

 the height of buildings on that street, let 

 us plant our maples, elms, poplars, lin- 

 dens, oaks, catalpas, and others similar. 



The sugar, red and Norway maples 



