STUDIES PRELIMINARY TO PLANTING 63 



proximity of sewers, water and gas mains to the proposed 

 line of planting, and all other conditions that could influence 

 vegetation favorably or unfavorably. Such records will be 

 found very valuable not only for the planting, but also for 

 the future care of the trees, particularly their watering, fer- 

 tilizing, and training, and approximation of their length of 

 life. 



Soil suitable for tree-planting must contain the elements 

 essential to vegetation, and must be of ample extent to sup- 

 ply the needs of the growing tree. An average light sandy 

 loam, easily worked, uniform, finely grained and smooth to 

 the touch, is ideal for trees. A heavy clay soil is unfavor- 

 able for trees, because it is not permeable to water and air, 

 and when it dries it becomes excessively hard and cracks. 

 A soil that is too sandy does not retain moisture necessary 

 to maintain vegetation. A soil containing on the average 

 about 70 per cent, sand, 20 per cent, clay, and 10 per cent, 

 humus is found to be suitable for most trees. Soil of aver- 

 age fertility contains in a dry state .1 per cent, to .2 per 

 cent., by weight, of nitrogen, .1 per cent, to .2 per cent, 

 phosphoric acid, .1 per cent, to .2 per cent, of potash, and 

 .4 per cent, to .6 per cent, of lime. When a soil fulfilling the 

 above conditions is found along the line of the proposed 

 planting, and the subsoil is pervious to water and permits 

 of good drainage, it will produce conditions for good growth 

 and long life of the trees planted. 



When choosing soil to replace poor street soil it is well to 

 observe the conditions making up the ideal soil and obtain it, 

 if possible. It is found that soil stripped from an old pas- 

 ture land, or other land which has had some cultivation, 

 makes the best earth for trees. When doing considerable 

 planting, it is a good plan to prepare a compost heap the 



