36 Defective Sorts. 
from the surface, must be overcome. The discussion of this 
point belongs to the chapter on ‘‘Cultivation.” Adobe soils are, 
as a rule, rich and durable and therefore promise long fruitful- 
ness to trees and vines with roots adapted to heavy soils, but 
difficulty of cultivation, excessive retention of water, and other 
evils are always present. Some suggestions on the treatment 
of such soils will be given in the chapter on fertilization. 
DEFECTIVE SOILS, 
Although California soils are predominantly of the depth, 
lightness and richness best suited to the growth and bearing of 
fruit trees and vines, it should always be borne in mind that 
there are marked exceptions, and failure to observe this fact 
has resulted in considerable disappointment and loss. There 
is in California much land which is bad from a horticultural 
point of view and it is apt to occur even in the vicinity of lands 
of the highest excellence. It is, therefore, necessary to advise 
that the closest examination be made before investment be made 
in the planting of fruits. 
Although there are instances of deficiency in plant food in 
California soils and considerable areas of land sterile through 
excess of saline and alkaline salts, these are usually indicated by 
the local reputation of the tracts, if the newcomer will take pains 
to make inquiry. It is rather the more obscure, subsoil condi- 
tions which lead to loss or failure, and they may be unknown 
even to men who have owned or iarmed the land for years for 
ordinarv field crops. These defects are, in the main, three:— 
Hard-pan.—Good loams may be underlaid near the surface 
by hard-pan or by layers of heavy clay. These prevent root 
penetration; they also limit moisture reception to the shallow 
surface layer, which is apt to become water-logged for lack of 
drainage during the rainy season or by excessive irrigation, and 
to quickly lose its moisture by surface evaporation in the dry 
season, with no compensation from the tight layer below. In 
such a situation, then, the plant may suffer severely from excess 
of water at one time of the year and lack of it at another. Such 
lands may serve well for some of the small fruits, but not for 
trees or vines. Under certain circumstances the defects of these 
soils may be corrected, as will be suggested in the chapter on 
preparing lands for planting. 
Leachy Sub-soiis—Good loams are also occasionally under- 
laid by layers of coarse sand or gravel, through which water 
flows away beyond the reach of roots which will only make 
measured progress through such matcrials. Trees in such situ- 
ations are apt to come into distress in the dry season and can 
only be comforted by frequency and volume of irrigation and 
