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CALIFORNIA FRUITS: HOW TO GROW THEM 



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 of 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 cracking 

 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 arrive sooner or later, according 

 to the disposition of the soil to run together by water settling. Dry- 

 ing 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. 



Where the surface is uneven or the soil too leachy to carry water 

 well in a ditch, portable and adjustable carriers are used to advan- 

 tage. Of these, slip-joint pipes of non-rusting metal or of wood, are 

 most satisfactory and are coming to be largely used. 



The Furrow System. The furrow system is the prevailing 

 method of irrigating fruit trees except with some soils which can be 

 better handled with less water by the check system. The furrow 

 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 distribution 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 became quite clear years ago that all these 

 theoretical advantages were not realized by the furrow system as 

 generally practiced, and a number of modifications were introduced 

 to secure their fuller realization. The changes tended toward re- 

 ducing the difference between what are known as the "large-fur- 

 row" and the "small-furrow" methods, because the improvement lies 



