84 CALIFORNIA VEGETABLES. 



sary to moisture-saving, and cross-plowing should follow 

 in preparation for planting. 



Land designed for spring planting of tender vegetables 

 should also receive early and thorough fall plowing and 

 a subsequent winter plowing or spring plowing before 

 the weed growth becomes too heavy for turning under or 

 so coarse that plowing under will make a non-retentive 

 soil still more prone to drying out the following summer. 



TILLAGE TO CONSERVE MOISTURE. 



Tillage to receive moisture designs to open the soil and 

 to assist percolation with a view to prevent surface flow 

 and to absorb the rainfall. Tillage to save moisture aims 

 to reduce evaporation to a minimum. In a firm soil moist- 

 ure rises by capillary attraction and is rapidly removed 

 from the surface by evaporation. A light soil has less 

 capillarity than a heavy one. A sandy soil has less than 

 clay, but both lose water by surface evaporation until, 

 in an arid climate, plants will die of thrist unless they 

 be by nature drought-resisting. Garden vegetables are 

 not of that character; in fact, quite the reverse. Conse- 

 quently, some means must be adopted to prevent the 

 moisture which is rising in the soil from reaching contact 

 with the outer air. This can be done by placing a cover- 

 ing upon the compact portion of the soil so that the air 

 shall not have free access to it. Covering with a sufficient 

 amount of almost any coarse material, such as coarse 

 manure or rotten straw or sawdust or anything of that 

 sort, is troublesome and expensive and otherwise objec- 

 tionable, although it has an acknowledged place in garden 

 practice, as will be shown later. 



The Earth Mulch. California practice has made the 

 widest application of the truth that a finely pulverized 

 surface layer of sufficient depth is an effective mulch. 

 Pulverizing the soil widens the distance between its par- 

 ticles and consequently destroys its capillarity until by 

 the action of moisture, either in the form of liquid or 



