20 College of Forestry 



residence streets in other cities are an extreme rarity in Man- 

 hattan. An open area of lawn or yard between the building 

 and the sidewalk is still rarer and practically does not exist 

 throughout 05 per cent, of the borough. In fact the growing- 

 conditions on the average residence street in Manhattan are 

 no better than, and often not as good as those of the business 

 street in the ordinary American city. 



As a result of all these factors the problem of growing- 

 trees on the majority of Manhattan streets becomes a totally 

 artificial one. The entire soil to contain the roots, together 

 with all food, air and water for the tree, must be supplied 

 artificially, much as they are supplied to house plants or to 

 trees grown in conservatories. That is, the tree must be 

 grown in a tree pit of prepared soil much as a plant is grown 

 in a flower pot. In some cases this pit must be provided 

 with concrete walls and underdrainage, while very com- 

 monly iron gratings or some form of protecting cover must 

 be installed over the surface of the pit. 



The entire problem of selecting the tree, its planting, 

 pruning and care must thus be radically different from 

 those of ordinary street tree practice, and likewise the cost 

 must be considerably larger than that for planting and main- 

 tenance in the average city or town. In certain boroughs of 

 New York City it has been estimated that a tree may be suc- 

 cessfully planted and cared for until established for eight 

 dollars, whereas a sidewalk grating alone on a Manhattan 

 street will cost several times this sum. In the City of New- 

 ark a tree can be planted and established for approximately 

 five dollars, while in Manhattan it will cost nearly this 

 amount to cut and remove the pavement above the pit in 

 which the tree is to be planted. 



If any plan or program for street tree planting in Man- 

 hattan is to be made it is very evident that a careful study 

 must be given to determine the following facts: 



(1) On what streets shall trees be planted? (The high 

 cost as above explained makes it impracticable to attempt to 

 plant the entire borough, and likewise the present and future 



