726 EXPERIMENT STATION RECORD. [Vol. 43 



silicates, and phosphates. Microscopic examinations of the solution and deposit, 

 immediately after preparation and after certain intervals, showed the forma- 

 tion of crystals with time. The clear solution after sedimentation was found 

 to contain gels of alumina, ferric hydroxid, and silicic acid. 



The conclusion is drawn that the peat used contains either organic acids or 

 related compounds, which are easily evaporated with steam, are readily soluble 

 in hot water, and not so soluble in cold water. 



Crop residue work in jars, F. J. Sievers (Washint/ton Sta. Bui. 155 {1920), 

 pp. J/0, /fl). — Data are summarized which point to the fact that the difficulty of 

 increasing the organic matter in Palouse silt loam soil becomes increasingly 

 greater as the natural supply in the soil becomes more and more depleted. 



The effect of straw on the soil, T. J. Murray {Washington Sta. Bui. 155 

 {1920), pp. 12, 13). — It was found that the addition of straw in amounts of 

 from 0.1 to 0.7 per cent actually stimulated the formation of nitrates in soil, 

 but when added in greater quantities there was a loss of nitrates in every 

 case. Total nitrogen determinations showed that although there was a loss in 

 nitrates and a decrease in nitrate formation, there was never any loss in total 

 nitrogen. 



Bacterial counts made on the soil showed that as the straw increased tlie 

 number of bacteria increase. Further studies showed that the addition of cellu- 

 lose to soil had no inhibiting effect on the nitrifying bacteria. 



The maintenance of soil fertility in Hamilton County, Ohio, C. E. Thorne 

 {Mo. Bui. Ohio Sta., 5 {1920), No. 6, pp. i70-i7.i).— Experiments on benefits 

 derived from fertilizers and limestone on a 4-year rotation of corn, soy beans, 

 wheat, and clover are reported. 



The financial estimate was based on corn at $1 per biishel, soy beans at $3. 

 wheat at $2, and hay at $20 per ton, and the cost of treatment on the basis of 

 16 per cent acid phosphate at $30 per ton, sodium nitrate at 6 cts. per pound, 

 potassium chlorid at 7.5 cts. per pound, manure at $1 per ton, and ground lime- 

 stone at $5 per ton. It was found that on this soil potassium may be nearly as 

 important as phosphorus. The test throughout indicated that the two legumi- 

 nous crops, soy beans and clover, were able to furnish all the nitrogen required 

 by the corn and wheat, and that the effect of manure was due to the phosphorus 

 and potassium carried. 



Wliere yard manure was substituted for chemicals, there was a drop in yield 

 which is explained- by the smaller quantity and lower availability of phosphorus 

 in the yard manure. The reinforcement of this manure witli phosphorus pro- 

 duced a further increase' in yield, but not sufficient to cover the cost of the 

 phosphorus. The addition of limestone to the manure caused a very decided in- 

 crease in yield. Two tons of untreated shed manure on one plat produced a 

 slightly larger increase than $14.25 worth of phosphorus and chemicals on an- 

 other plat. Two tons of powdered limestone applied every fourth year appar- 

 ently increased the 4-year yield. 



Investigational Avork with fertilizers, F. T. Shutt {Canada Expt. Farms 

 lipt. 1919, pp. Jf7-49, 50). — Progress results of the complete fertilizer series of 

 experiments indicate the following salient features: (1) The very striking 

 lack of productiveness on the permanent check plat which for more than five 

 years received neither manure nor fertilizers, (2) the uniformly low standing 

 of the checks which received only the initial light dressing of manure and no 

 fertilizer, (3) the beneficial influence of additional manure when used in con- 

 junction with fertilizers, (4) the distinctly lower yields produced from heavy 

 applications of manure alone as compared with those from the practice of sup- 

 plementing smaller quantities of manure with fertilizers, (5) the probability 



