192 



CALIFORNIA FRUITS: HOW TO GROW THEM 



ridge above, is dropped through a box, or otherwise let down, from 

 the low end of one terrace to the high end of the next, and so on 

 until the stream reaches the bottom of the slope. As a basin is 

 reached it is filled and closed and the water sent along to the next 

 and so on. As these basins are usually small and shallow they 

 are filled two or three times in succession at each irrigation. 



Wherever water can be handled in contour ditches or furrows, 

 terracing should seldom be undertaken for commercial purposes. 

 With slopes which do require terracing, basins on the steeper parts 

 are largely made by hand labor, after plowing to loosen the whole 

 surface, and the operation consists in moving the earth from the 

 upper side of the tree, so as to form a circular levee on the lower 

 side, until the tree stands in a level, roundish pan as large as can 

 be made without too much excavation and filling. As the slope 

 becomes less the basins enlarge and reach a diameter, finally, 

 where the sides can be made by turning a small horse or mule 

 around the tree with a plow, the .rim being further raised and 

 shaped by hand so as to hold 3 inches or more of water without 

 danger of breaking away. 



The basins are filled with a small stream by ditch or hose or 

 pipe line, according to the ground and notion of the irrigator. They 

 are filled at such intervals as the water supply admits or the growth 

 seems to need. The basin bottom is rarely disturbed. The crack- 

 ing soil is finally given another dose of water to close up its 

 wounds; meantime the frequent surface soaking puddles the soil 

 and the conditions unfavorable to growth arrives sooner or later, 

 according to the disposition of the soil to run together by water 

 settling. Drying and cracking is lessened by filling the basin 

 with manure or rotten straw or other light rubbish, or by a layer 

 of coarse sand on the bottom. As the tree grows the foliage 

 shades the basin and thus reduces evaporation. 



The Furrow System. The furrow system is the prevailing 

 method of irrigating fruit lands except with some soils which can 

 be better handled with less water by the check system. The fur- 

 row system has, however, a very marked theoretical advantage 

 in the escape from saturating the surface soil, which has to dry 

 out again before it can be cultivated, and it is only with difficulty 

 reduced to fine tilth after such puddling. Another advantage is in 

 saving the water used in moistening soil which has to be dried 

 by evaporation. Other theoretical advantages lie in the even dis- 

 tribution of the water with the least displacement of the soil and 

 the introduction of the water to the subsoil, where deep-rooting 

 plants should derive their chief sustenance. It is becoming quite 

 clear that all these theoretical advantages have not been realized 

 by the furrow system as generally practiced, and a number of 

 modifications are now being introduced which promise their fuller 



