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 European 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, irrespective 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 below the surface and in some places 12 inches?  I have been plowing so I could set peach trees, but I have been told that they will not grow.  I would like your opinion about it.  I intended to blast holes for the trees, and the water is 30 feet from surface.  The top soil is red sandy and clay mixed, but it works very 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 hardpan 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, indispensable.

Depth of Cultivation.

I would be glad to know whether in cultivating an orchard a light-draft harrow could profitably be used, which cultivates three and a half inches deep?  I have used another cultivator, and try to have it go at least seven inches.

A depth of 3 1-2 inches is not satisfactory in orchard cultivation, although there may be some condition under which greater depth would be difficult to obtain because of root injury to trees, which have been encouraged to root near the surface.  Both experience and actual determinations of moisture in this State show that cultivation to a depth of 5 inches conserves twice as much moisture in the lower soil as can be saved by a 3-inch depth of cultivation under similar soil conditions and water supply.  It is all the better to go 7 inches if young trees have been treated that way from the beginning.

Alfalfa Over Hardpan.

I have land graded for alfalfa and some of the checks are low and water will stand on the low checks in the winter.  There is on an average from two to three feet of soil on top of hardpan and hardpan is about two feet thick.  Will water drain off the low checks if the hardpan is dynamited, and will this land grow alfalfa with profit?

Yes; much of the hardpan in your district is thin enough and underlaid by permeable strata so that drainage is readily secured by breaking up the hardpan.  Standing water on dormant alfalfa is not injurious.