SOILS FERTILIZERS. 125 



inoldboard plows on a deep, well-drained soil varying in texture from clay loam 

 to gravelly silt loam are reported, the crops for which plowing was done being 

 corn, oats, barley, wheat, and alfalfa. 



The deep-tilling machine is a double-disk plow with 24-in. disks, the front 

 disk being a few inches to the land side of the rear disk and not so deep. It 

 cuts from 4 to 8 in. deep and throws the soil over into the furrow. The rear 

 disk penetrates G to 9 in. deeper and mixes the plowed soil thoroughly. 



Eight plats 35.5 ft. wide, varying in length from 9S2.5 ft. to 1,000 ft. long, were 

 plowed at first, later being made 957.2 ft. long and comprising 0.7S of an acre 

 each. Timothy sod was plowed for corn in the fall of 1909 and the spring of 

 1910, two plats being plowed with each implement in the fall and two in the 

 spring. In the fall of 1910 and the spring of 1911 the corn stubble land was 

 plowed in the same way and in the spring four plats were seeded to oats and 

 four to beardless barley and alfalfa. In the fall of 1911 the four plats which 

 had received oats were plowed and seeded to wheat, two plats being plowed with 

 each implement. Under these conditions the two kinds of plowing gave prac- 

 tically the same results for all the crops grown. 



The draft of the deep-tilling machine averaged in three sets of trials 1,727, 

 1,202, and 937 lbs., respectively, and the draft of the moldboard plow In the 

 same trials in the order given averaged G55, 424, and 378 lbs. The draft of the 

 deep-tilling machine per square foot of cross section of furrow averaged in the 

 order given 1,512, 856, and 970 lbs. and that of the moldboard plow in the same 

 order 9G2, 680, and 531 lbs. 



Influence of dynamiting' on soils, W. R. White {Pennsylvania Sta. Rpt. 

 1913, pp. 703-725, pis. 4, figs. 3). — Experiments conducted to determine the in- 

 fluence of dynamiting on (1) the physical condition of soils, (2) soil moisture 

 and drainage, (3) newly planted fruit trees, (4) mature trees, (5) field crops, 

 and (6) insects in the soil are reported. The soils used were the Hagerstown 

 clay loam and Yolusia silt loam. 



From these experiments it is stated that "while the results . . . can not be 

 taken as conclusive for all conditions, yet they may indicate that the useful 

 application of dynamite as a soil improver is limited. Its usefulness may depend 

 largely upon local conditions. No definite benefits were derived from its use in 

 either orchard or field crops. What it might do under different conditions, or 

 over longer periods, is yet to be determined. One pond was drained and the 

 other was not. Its usefulness in shooting an open ditch, blasting bowlders, and 

 blowing stumps can not be questioned. It may be very useful in draining land 

 where no outlet can be found for a tile drain. How permanent its effect may 

 be is not kno^vni. As to destroying insects [ants], it has not proved to be of any 

 use. It is probably safe to conclude that the application of dynamite as a soil 

 improver is greatly limited and that it would always be advisable to try it out 

 In a small way before investing much money in its use." 



Effect of alkali salts in soils on the germination and growth, of crops, 

 P\ S. Haeris (V. S. Depf. Ayr., Jour. Ayr. Research, 5 {1915), Xo. 1, pp. 1-53, 

 figs. 48). — Investigations conducted at the Utah Experiment Station on the 

 effect of the chlorid, sulphate, nitrate, and carbonate of potassium, and sodium, 

 the chlorid of calcium, the sulphate, chlorid, and nitrate of magnesium, and the 

 carbonate of ammonium, singly and in different combinations and in concen- 

 trations varying by degrees from to 10,000 parts per million, on the growth of 

 barley, oats, wheat, alfalfa, sugar beets, corn, and peas in loam soils and sand 

 are reported, the purpose of the study being to determine the quantity of various 

 alkali salts necessary in the soil to reduce the growth of crops beyond the point 

 of profitable production. About 18,000 determinations are summarized. 



