36 CALIFORNIA VEGETABLES 



state of affairs has not arisen in California yet, for the reasons 

 shown in the descriptions of our garden soils, and yet we do not 

 mean to suggest that the farm gardener should in all cases expect 

 to reach satisfactory results without due effort for soil improvement 

 on the small area which he expects to yield so much. 



Improvement of Adobe Soils. Our adobes, especially those of 

 the darker hues, are rich and durable. In common with heavy clay 

 soils everywhere they are retentive of moisture. In our arid sum- 

 mers, however, they lose their moisture speedily by evaporation, if 

 untilled, and dry out to a greater depth than lighter soils. They are 

 refractory under tillage and unless caught at just the right moment 

 they are either wax or rock under the plow, and the cultivator will 

 either stick fast or ride over the surface. And yet if one has 

 nothing but adobe he is not as badly off as he might be, because 

 adobe is easily susceptible of improvement. The points to attain 

 are several, but they are inter-related and effort for one measurably 

 helps toward all. 



The free used of burned lime, either as it comes from the kiln 

 for builder's use or when air-slaked or water-slaked (hydrated), and 

 applied about the time of the first rains is the first and simplest 

 effort toward breaking up the tenacity of the soil. This should be 

 done no matter what greater efforts are to be undertaken later. 



Deep and thorough tillage, taking the soil at just that condition 

 of moisture when it works well with plow and harrow, will be found 

 to progressively improve its tillability by mere action of air and im- 

 plements. If this is all that can be undertaken at first, do this thor- 

 oughly and put in the cultivator after each heavy rain as soon as 

 the proper condition of soil arrives, so as to prevent baking of the 

 surface. For winter growth of vegetables in regions of ample rain- 

 fall, use the ridge system, which will be described in a subsequent 

 chapter. 



But liming and persistent tillage are only temporizing with 

 adobe and do not accomplish permanent reform. The first rational 

 step is to resort to adequate drainage. Tile drains two and a half 

 or three feet deep and twenty feet apart will do for garden plants. 

 This leaves a clear surface for working over, but, if the expense 

 of tiling is not desired, open ditches will answer, but they restrict 

 cultivation to one direction, waste land, and are expensive in hand 

 work in killing weeds in the ditches. Open ditches, are, however, 

 better than no ditches at all. The effect of drainage is to promote 

 friability, to render the soil tillable earlier and oftener, by the quick 

 removal of surplus water, and to promote seed germination and 

 plant growth. 



.The aeration of adobe by drainage and tillage accomplishes a 

 considerable improvement, but still more radical reform measures 

 are desirable. The soil particles are naturally too small. They must 

 be separated by interposition of coarser grains. Plow into the soil 

 as much coarse material as possible. Farmyard manure, straw, 



