104 Forest Club Annual 



thus removing the bark. In all cases injuries of this kind 

 can be prevented if the trees are protected by a covering of 

 boards, a cylinder of iron or other material substantial enough 

 to bear the strain put upon it. 



If horses are tied to trees, they are almost sure 

 to cause injury by gnawing the bark from the trunk and lower 

 branches. A wire netting placed around trees in localities 

 where horses are likely to be tied will prevent this kind of 

 injury. 



QUALITIES THAT STREET TREES SHOULD POSSESS 



Hardiness. 



All trees should possess certain characteristics in order 

 to be desirable for street planting. In the first place, a tree 

 must be hardy and capable of withstanding unfavorable con- 

 ditions such as poor soil, drouth, smoke, gases, heat and dust. 

 It must possess strength to resist strong wind, sleet and snow, 

 and must have the ability to recover its normal position when 

 the pressure is removed. It must also endure transplanting 

 well and be easily propagated. 

 Form. 



A street tree should have a straight stem, a round, well- 

 shaped crown and should be symmetrical in growth. The 

 natural habit of growth should be preserved as far as possible, 

 but the requirements of the public may demand some pruning. 

 Low branching or crooked trees have no place along the streets 

 and should be confined entirely to the lawn. 

 Immunity. 



Insects and fungi cause much injury to trees especially 

 when in a weakened condition. Some species are more subject 

 to injury than others; the lindens and horse chestnuts suffer 

 severely while the oaks are comparatively immune. It is 

 desirable to secure trees which are ordinarily free from pests 

 so that much trouble and expense may be avoided. 

 Shade-production. 



Trees should possess enough lea,ves to furnish shade with- 

 out depriving the street of all sunlight, preventing the growth 

 of grass underneath, and at the same time allowing a rapid 

 evaporation of water from the street after rain. A desirable 

 tree is one that is not greatly affected by changes of moisture 

 but will retain its foliage in good condition throughout the 



