118 EXPERIMENT STATION EECORD. 



Neither phosphorus nor potassiinu increased the yield of corn iH'.vond that 

 obtained from tlae use of a leguminous crop and lime. 



In pot culture experiments made with red silt loam of unglaciated hill land 

 there was practically no gain except when nitrogen was supplied either directly 

 in commercial form or indirectly by means of a leguminous crop. The effect of 

 phosphorus and potassium was less where decaying organic matter had been 

 provided in the leguminous crop than where the nitrogen was given in com- 

 mercial form with but little organic matter. Since 1005 practically no effect 

 has been observed from either phosphorus or potassium when applied in con- 

 nection with growing leguminous crops for soil improvement. These results 

 bear out conclusively the results obtained in the field tests, that marked 

 improvement can be made on this soil by turning imder leguminous crops where 

 lime has been applied. 



Another series of pot culture experiments was made with soil from worn gray 

 silt loam hill lands of northwestern Illinois. In these tests the amount of oats 

 secured where nitrogen was applied was aliout 8 times that where no nitrogen 

 was given. Lime alone produced no beneficial results, thus indicating that lime 

 and nitrogen together are necessary on this laud. 



Notes are given on crop rotations, the use of the crops, and the use of fer- 

 tilizers in soil improvement. A rotation for the worn hill lands of southern 

 Illinois, consisting of corn the first year, cowpeas or soy beans the second, 

 wheat the third, clover and timothy meadow the fourth, and pasture the fifth 

 and sixth years is suggested. 



Improvement of upland timber soils of Illinois, C. G. Hopkins and J. E. 

 Readhimer {Illinois fSta. Clrc. 109, pp. S). — This circular briefiy summarizes the 

 more practical results of field experiments carried on in a representative area 

 of the ordinary gently rolling upland timber soils of northern and central Illi- 

 nois. The profitable system of improvement for such soils, as indicated by the 

 results of these experiments, " is to grow legumes in the crop rotation and 

 make as much manure as possible to maintain the supply of hiunus and nitrogen 

 and to purchase somewhat more phosphorus, in the form of pure steamed bone 

 meal or fine-ground r;nv rock phosi)hate, than is removed from the soil by crop- 

 ping, so that the soil will grow richer rather than poorer." 



The action of water and aqueous solutions upon soil phosphates, F. K. 

 Cameron and .1. ^l. Bell {U. >S'. Dept. A(/r.. Bur. Soils Bui. '/l. pi). .IS. flf/x. .',). — 

 This bulletin reviews the literature bearing on this subject and reports experi- 

 ments on the action of water on mouocalcium, dicalcium, and tricalcium phos- 

 I)hate; the behavior of the three-component system— lime, phosphoric acid, and 

 water — and the four-component system — lime, phosphoric acid, sulphuric acid, 

 and wa!:er ; the action of solutions of carbon dioxid, sulphurous :icid, citrates, 

 ammonimn comiuninds. calcium salts, i»otassium chlorid, sodium nitriite and 

 chlorid, and other solvents cm the phosphates of calcium: and of the behavior 

 of sui)eri)h()sphates and magnesium, iron, and aluminum phosphates under 

 similar treatment. The following is the authors" summary: 



" In this bulletin it has been shown that the soil phosphates are decomposed 

 or hydrolyzed by water, with the formaticm of other phosphates containing 

 relatively more of the base. 



" Neutral salts in solution have a marked effect ui»on the amount of phos- 

 phoric acid and of lime going into solution from a lime phosphate, generally 

 increasing both. Lime salts generally decrease the amount of both in solution, 

 as do alkaline solutions, while acid solutions increase it. 



" Neutral salts have, however, little effect ui)on the solubility of the phos- 

 phates of iron or alumina, and it is impossible to predict the direction of the 



