THE RAISIN INDUSTRY. 



Many changes have occurred since raisin growing became an in- 

 dustry in Orange County, and Fresno has become the center of the 

 industry, as the conditions there are exceptionally suited to the grow- 

 ing and curing of raisins. 



RAISIN-VINEYARD SOIL. 



Raisin-vineyard soils vary considerably, the deep-gray alluvial bot- 

 tom land being considered the best. In this connection the mechanical 

 analysis of the soil in the department experiment vineyard near 

 Fresno, made by the Bureau of Soils, and shown in Table III, will 

 prove interesting. 



Table III. — Analysis of the soil of the Fresno Experimental Vineyard at 



Fresno, Cat. 





Mechanical constituents (per cent). 



Description and depth of soil. 



Coarse 

 gravel. 



Fine 

 gravel 

 (2tol 

 mm.). 



Coarse 



sand 



(lto 



0.5 



mm.). 



Me- 

 dium 

 sand 

 (0.5 to 



0.25 

 mm.). 



Fine 

 sand 

 (0.25 

 to 0.1 

 mm.). 



Very 

 fine 



sand 



(0.1 to 

 0.05 



mm.). 



Silt 



(0.05 to 



0.005 



mm.). 



Clay 



(0.005 

 mm. 

 and 

 small- 

 er;. 



Brown sandy loam: 



to 12 inches 



0.58 

 .71 



.51 

 .35 



.11 



1.2 

 .9 



.6 

 .9 



1.2 



9.8 

 9.1 



8.3 



8.8 



14.2 



6.7 

 6.9 



7.8 

 6.0 



8.6 



18.4 

 17.8 



19.9 

 13.7 



22.4 



12.0 

 12.3 



12.9 

 13.1 



15.7 



33.2 

 32.5 



27.1 

 36.3 



26.5 



19.7 





21.4 



Sandy loam: 



24 to 36 inches 



23.5 



36 to 48 inches.-. 



21.4 



Free sandy loam: 



4£ to 60 inches 



11.1 







Of this type of soil about 75,000 acres near Fresno, 6,000 near 

 Stockton, and about 265,000 in the Sacramento Valley have been 

 mapped by the Bureau of Soils. For a further description of the 

 soils, see Bureau of Plant Industry Bulletin 172 and the surveys of 

 the Bureau of Soils. 



PREPARATION OF SOILS. 



In the raisin-producing sections of California the country is nat- 

 urally so level that not much grading is necessary. After the land 

 has been leveled where needed it should be well prepared. If virgin 

 soil is to be used, it will allow the field to be put in better shape if a 

 crop of grain is grown on it the season before planting. After being 

 plowed and subsoiled, it should be thoroughly harrowed and clod- 

 crushed with a drag or roller. In the early stages of the industry 

 most of the vines were planted 7 feet apart each way (PI. I, fig. 1). 

 The tendency now is to plant farther apart, some planting 8 feet 

 apart each way (PI. I, fig. 2), others 6 by 10 feet, 9 by 9 feet, 8 by 10 

 feet (PL I, fig. 3), or even wider distances apart. Trellises are the 

 exception (PL II, fig. 1) ; usually stakes are simply used to support 



