78 TREES IN WINTER 



Parking Strips — With very wide streets it is customary to re- 

 serve "parking strips" down through the center for the planting 

 of one or more rows of trees. Such reservations are not recom- 

 mended for streets less than one hundred feet in width. Where 

 two rows of trees are required on this strip, and this is always ad- 

 visable, the street should be at least 130 feet in width. The park- 

 ing- strip when narrow is often used for the planting of shrubbery 

 alone. Wider strips are often used for walks, bicycle paths, and 

 street railway tracks. 



Very pleasing planting effects may be produced on wide streets 

 or avenues with parking strips to accommodate two additional rows 

 of trees. While it is customary to plant but one species on ordinary 

 streets, the appearance of avenues or boulevards may be greatly en- 

 hanced by planting a strikingly different species along the parking 

 strip. On some of the widest streets we frequently find two rows 

 along each side of the street. This arrangement is seldom satis- 

 factory for the reason that the trees are likely to become too crowd- 

 ed. Streets that are wide enough to accommodate four rows of 

 trees are usually wide enough for a parking strip which would ac- 

 commodate two rows of trees and thus give a better distribution. 



Distance Between Trees — It is well to adopt a uniform system 

 of spacing the various varieties of street trees. The individuals 

 should be so spaced that they may develop into perfect specimens. 

 The distance between the trees should be slightly in excess of the 

 natural spread of the species when mature. Of course, such factors 

 as environmental conditions, the character of the soil, the severity 

 of the climate, and the amount of protection the trees receive, will 

 exert considerable influence upon the ultimate development. The 

 distance at which the commonly planted street trees should be 

 spaced is about as follows : — 



White Ehn 50 feet 



Sycamore 45 *^ 



Sugar Maple 45 '^ 



Silver Maple 45 " 



Sycamore Maple 45 ^^ 



Red Maple „ 40 " 



Norway Maple 40 ^' 



White Oak 50 " 



Scarlet Oak 45 " 



