374 THE COMPLETE GARDEN 



Is the result of the action of heat, frost, air, cultivation, surface or rain 

 water, soil bacteria, etc. It is of finer particles than the subsoil, 

 darker in colour, and looser in texture, and is rich in organic matter. 

 A good topsoil, thoroughly dried, should contain 30 to 40 per cent, 

 voids, when well shaken down in a box; that is 30 to 40 per cent, of 

 its own volume of water should fill it to saturation but not increase 

 the volume of the soil. It should contain from 40 to 60 per cent, 

 of this amount of water to properly support plant life. 



Training : 



A procedure consisting principally of judicious pruning to adapt 

 plants to limited areas or to form particular shapes, also to encourage 

 the formation of flowers and fruit. 



Transpiration: 



The giving off of water vapour through the leaf pores of the plant. 



Transplanting: 



To remove a plant from one location and plant it in another location. 



Tree: 



A woody perennial, having a single main trunk. 



Tree Pit: 



A pocket or pit excavated to permit the introduction of sufficient 

 fertile soil to support a tree; a common practice in planting street 

 trees in city streets. The surface of the soil in the pit should be suf- 

 ficiently lower than the surrounding area so that much of the rain 

 falling on the surrounding area will flow to the pit, and the bottom 

 of the pit must be well drained to remove excess water. 



Trench: 



v. To spade ground so deeply that the digging of ditches is nec- 

 essary; hence to spade ground to two or more times the depth of a 

 spade. In landscape work trenching is usually done for the purpose 

 of saving good topsoil that has been buried under useless subsoil and 

 also for the purpose of mixing manure and fertilizers into soil to a 

 depth of one or more feet, especially in the vicinity of large trees and 

 garden areas. 



Turf: 



The upper stratum of earth which is filled with roots of grass; sod. 



