ON TREES AND SHRUBS IN LARGE TOWNS. 293 



Loam, in all its varieties, is a soil in which most trees 

 arid shrubs thrive well. It requires nothing more than 

 loosening to the depth of 2 feet 6 inches, and enriching by 

 the addition of manure, much or little, according to its 

 natural poverty or richness. There may, however, be 

 extreme cases in which the loam is so light that it can be 

 improved by the addition of clay or marl, or so heavy 

 that a portion of sand would be valuable. 



Peal, if not wet or too sandy, will suffice for the 

 prosperity of many trees and shrubs, and here manure 

 and clay are valuable improvers. Many kinds of peat 

 are precisely the thing for Rhododendrons and Azaleas, 

 but we have found them thrive equally well in light 

 fibrous loam. Wet peat bogs are a bad soil for most 

 trees, because they are at once poor and sour, and are 

 best improved by draining and exposure to the air for 

 some months previous to the introduction of the trees, at 

 which time manure may be added. 



Clay should also be exposed to the air for some 

 months before planting in it ; if wet, it should be drained 

 and enriched and ameliorated by manure and sand or old 

 mortar, the debris of old brick buildings. 



Chalk is not a bad subsoil, as it is cool, though poor; 

 and if it comes within 2 feet 6 inches of the surface, it 

 should be removed to that depth, and replaced with loam 

 and manure. Rhododendrons abhor chalk, and should be 

 kept from the influence of water containing its properties 

 in solution. 



Sand and Gravel are bad soils for trees, because poor 

 and dry, and they should be removed to the depth of 

 2 feet 6 inches at the least, and replaced with loam and 

 manure. 



All soils that are wet should be drained, for few 

 trees will thrive long if their roots are placed in stagnant 

 water. 



When preparing beds or borders for trees, the whole 

 of the soil should be loosened by trenching to the depth 



