Soils, Fertilizers and Irrigation 147 



to fail outright. The best treatment would consist in keeping the 

 soil around the roots continually moist, yet not too wet. The upper 

 part of the holes should be filled loosely and the ground kept from 

 surface compacting. The maintenance of such a condition during 

 the coming summer will probably allow the trees to overcome the 

 mistake made at their planting, unless the soil should be a tough 

 adobe or other soil which has a disposition to act like cement. 



Electro-Agriculture. 



Kindly tell me of any one zvho is zvorking upon the application of 

 electricity to stimulating agricultural grozvtii — especially here on the Coast. 

 A friend zvho has done some zvork in this line seeks to interest me. I 

 have seen notices of this zvork, and have read of Professor Arrhenius 

 stimulating the mental activity of children, etc., but I desire more definite 

 information, if possible. Does the idea seem to you to be feasible? 



So far as we know, there has been no local trial of the effect of 

 electric light in stimulating plant growth. Much has been done with 

 it in Europe and in this country. There is much about it in Euro- 

 pean scientific literature. It is perfectly rational that increased 

 growth should be attained by continuous light in the same way, 

 though in less degree than occurs in the extreme north during the 

 period of the midnight sun. It is known that moonlight, to the 

 extent of its illumination, increases plant growth, and it has been 

 amply demonstrated that light is light, just as heat is heat, irre- 

 spective of the source thereof. Of course, the commercial advantage 

 must be sought in the relative amount of increased growth and the 

 selling value of whatever is gained in point of time. 



High Hardpan and Low Water. 



What detriment is hardpan if 14 inches belozv the surface and in some 

 places 12 inches? I have been plozving so I could set peach trees, but 1 

 have been told that they zvill not grozv. I zjuould like your opinion' about 

 it. I intended to blast holes for the trees, and the zvater is 30 feet from 

 surface. The top soil is red sandy and clay mi.vcd, but it zi'orks zrry 

 easily. 



You cannot expect much from trees on such a shallow soil over 

 hardpan without breaking it up, because the soil mass available to 

 the trees is small; also because the shallow surface layer over hard- 

 pan will soon dry out in spite of the best cultivation, because there 

 is no moisture supply from below. If such a soil should be selected 

 for fruit trees at all, the breaking through the hardpan by dynamite 

 or otherwise is desirable, and irrigation will be, probably, indis- 

 pensable. 



Depth of Cultivation. 



/ zvould be glad to knozv zdtethcr in cultivating an orchard a light- 

 draft harrozv could profitably be used, zvhich cultivates three and a half 

 inches deep? I have used another cultivator, and try to have it go at 

 least seven inches. 



