A Street Tree System for New York City 59 



fertilizer in growing street trees conditions and experience 

 must guide our practice. 



As has already been noted, great variation in use and con* 

 ditions between different streets makes any single method 

 of planting or any hard and fast planting specification un- 

 wise. If such a single standard should be adopted it would 

 be extremely inefficient. If a specification were selected 

 which would be appropriate for streets where conditions 

 are unfavorable it would entail a large and unnecessary ex- 

 pense for planting under more favorable conditions. On 

 the contrary a specification suitable for streets with favor- 

 able growing conditions would result in failure on many 

 others. With this idea in mind several types of planting 

 with their corresponding specifications have been suggested. 

 Some one of these types will be found suitable for every 

 Manhattan street in which planting is possible or advisable. 



The various streets upon which planting is suggested may 

 be grouped into three general classes with regard to the type 

 of planting appropriate for each. 



I. Those streets where growing conditions are very good, 

 and where trees can be planted in grass or gravel parkings. 

 (Planting to be done according to Planting Spec. No. 1.) 



II. Those streets where growing conditions are reasonably 

 good, and where trees can be planted in parking areas or 

 tree pits either with or without sidewalk grating or other 

 form of ground surface protection and where light tree 

 guards are sufficient. (Planting to be done according to 

 Planting Spec. No. 2 and 3.) 



III. Those streets where growing conditions are hardest, 

 and where the trees must be planted in small tree pits and 

 provided with gratings and where on account of the traffic 

 heavy guards are necessary. Planting to be done according 

 to Planting Spec. No. 4 and 5. 



The accompanying map shows our proposed and pos- 

 sible street tree system divided into these three classes or 

 zones differentiated on the map by color.* 



* This map being of purely administrative value has been omitted 

 from the published report. 



