42 CALIFORNIA GARDEN FLOWERS. 



is doubtful whether the time will ever come when such systems and 

 devices will replace well-regulated surface distribution and the cultiva- 

 tion which is associated with it, though for economy of water, and to 

 escape the refractory condition which some soils assume upon surface 

 irrigation, experimentation in this line certainly commends itself to 

 those whom the theory pleases. 



Distribution through tile laid upon the surface is available for 

 shallow-rooting plants, and has been shown to be economical both of 

 labor and water under Eastern conditions. In an arid region, how- 

 ever, the prevention of surface stirring of the soil is a decided objec- 

 tion to the system, unless the soil be very light and free from a 

 tendency to bake. Surface applications not followed by stirring are 

 not a substitute for cultivation, as discussed earlier in this chapter. 

 It is a common experience of beginners that plants may dwindle and 

 fail, though water may be almost daily poured around them, on an 

 uncultivated surface. Each new application seems to add to the 

 compact and inhospitable character of the soil. 



GARDEN TILLAGE. 



The importance of adequate soil-stirring or tillage has been urged 

 in the discussion of the relations of tillage to soil moisture arid thrift 

 of the plant.* It will also intrude in many other connections in suc- 

 ceeding chapters, for tillage is the ruling art in gardening, related to 

 all other arts and often actually determining their success or failure. 

 Therefore no elaborate, separate discussion of tillage will be under- 

 taken for its most important phases will inevitably pervade this 

 treatise in all its parts. Still for connected view of so important a 

 matter a quick, comprehensive glance at the purposes of tillage will 

 be taken. 



Tillage is the general term including all forms of soil-stirring 

 from light touch of smoothing rake at the surface to heavy wrench 

 of dynamite in loosening the subsoil, and its offices may be categorized 

 as follows: 



1. To open the soil: (a) to reception of moisture and air; (b) to 

 receive and distribute fertility; (c) to afford fine particles for seed- 

 enclosure and root-seizing; (d) to promote porosity and root ex- 

 tension; (e) to promote drying when moisture is in excess. 



2. To close the soil: (a) to break clods and reduce air-spaces in 

 and under turned-soil, by harrow, sub-soil packer or thrust of spade; 

 (b) to reduce surface soil to granular or "crumby" condition (and to 



* Quite fully discussed in "California Fruits," Chap. XIII and "California Vege- 

 tables," Chap. VII, 



