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CALIFORNIA FRUITS: HOW TO GROW THEM 



furrows, from 3 to 5 feet apart, are most generally used. In heavy adobe 

 soils more furrows are used than in the more porous granite soils. The most 

 usual length of furrows is 40 rods. Every precaution is taken to have the 

 surface wetted as little as possible. 



The amount of water run at a time is materially lessened, formerly the 

 common practice was to run 3 inches per acre for twenty-four hours each 

 thirty days. Now 2 incres continuous run for seventy-two hours is found to 

 serve a much better purpose, except on loose soils. The general practice in 

 the valley is to irrigate once each thirty days. A few of the most careful 

 orchardists had found that by intelligent and thorough manipulation of the 

 soil they obtained as favorable results from the application of water every 

 sixty days or more, using the same amount as they formerly did at intervals 

 of half that time. The writer has watched with much interest an eight-year- 

 old orchard that during the three years preceding the present received in all 

 but ten irrigations, the usual amount of water being used only at each four 

 irrigations the first year and three irrigations each the second and third 

 years, with results comparing favorably with those on trees of the same age 

 on the same soil in neighboring orchards that received the ordinary thirty- 

 day irrigations. While there are few orchardists who have the skill and 

 patience required to secure such results, they show the possibilities of im- 

 proved cultivation in conserving moisture. So long as water is abundant and 

 not expensive, more frequent irrigations will probably be generally practiced; 

 but the advantage of running the water for a longer time, in furrows as deep 

 as possible, covering the saturated bottoms as soon as practicable and keep- 

 ing the surface perfectly pulverized and in loose condition, is being generally 

 recognized 



The usual practice is now to have six deep furrows in 20-foot 

 spaces. The number varies according to the character of the soil, 

 but is in any case less than in the small, shallow furrow system 

 which formerly prevailed. 



The recourse to deeper furrows and to the subsoil plowing has 

 been made in several citrus fruit districts of Southern California. 

 Its success depends upon conditions. There are cases in which too 

 deep use of the subsoiler has admitted the water at a point too low 

 for best results to the tree which grows on a leachy subsoil, and the 

 cutting of roots by the subsoiler has in some cases brought shallow- 

 rooting trees into temporary distress. The general conclusion, how- 

 ever, is that deeper introduction of water favors deeper rooting and 

 is very economical of water by preventing the loss by evaporation 

 from the surface, which, theoretically, is dry, but which actually, 

 with shallow furrows over an irrigation hardpan, becomes too often 

 saturated over nearly the whole space between the trees. 



Cement Pipes and Flumes for the Furrow System. The use of 

 cement in the construction of flumes, pipes and outlets for distribu- 

 tion has advanced so rapidly during recent years that in nearly all 

 districts local cement works can be found, at which irrigation struc- 

 tures and appliances of latest design can be studied. Other devices 

 are first described and afterwards regularly advertised in our horti- 

 cultural journals. Analysis of them is beyond the scope of this 

 treatise, but they are none the less important and all who contem- 

 plate laying out irrigation systems, both large and small, should 

 consider them carefully. It is the function of this work to deal 

 chiefly with home-made appliances. 



The Board Flume and the Furrow System. Although in the 

 older regions the cement flume is advancing in popularity, important 



