530 EXPERIMENT STATION RECORD. [Vol.35 



calcium carbonate per acre to correct it to tlie depth of 7 in., clover failed and 

 sorrel took its place ; where from 4,000 to 4,500 lbs. of calcium carbonate were 

 similarly required, timothy was largely replaced by sorrel ; and where the maxi- 

 mum acidity was reached red top predominated. Plats receiving calcium as 

 sulphate and carbonate are reported as free from sorrel. 



In the pot experiments the greatest yield of clover occurred where limestone 

 was applied at the rate of 3 tons per acre in excess of the quantity required to 

 render the soil neutral. Clover failed in these tests where the acidity for its 

 correction required from 3,000 to 3,500 lbs. of calcium carbonate per acre for the 

 upper 7 in. of soil. Where limestone was present in slight excess in the pot 

 experiments, sorrel was largely replaced by clover, but it produced the highest 

 yield where the maximum amount of limestone was applied. 



The calcium content of clover and sorrel was highest where the largest quan- 

 tity of limestone was added to the soil. The protein content of clover was 

 found to vary but slightly whether grown in an alkaline or an acid soil. The 

 calcium content of sorrel grown on plat 32 was determined as only 10 per cent 

 of that grown in an alkaline soil. The leaves of sorrel grown on this plat con- 

 tained 17.92 per cent protein, equivalent in amount to that in clover, and the 

 sorrel contained per ton of dry matter the equivalent of $9.03 in nitrogen, 

 potassium, and phosphorus as compared with the corresponding value of $10.97 

 for clover. The water-soluble acidity of the sorrel from this plat calculated to 

 oxalic acid was found to be as follows : Total plant 1.36 per cent, leaves 2.45 

 per cent, stem 0.969 per cent, and seed 0.44 per cent, as compared with 0.98 per 

 cent in the whole plant grown on alkaline soil. 



On the basis of these results the author concludes that sorrel is not an acid- 

 loving plant but has the property of adaptation under soil conditions unfavor- 

 able to the growth of most field crops. 



Winter injury of alfalfa and clover, C. A. Geakhakt {Mo. Bui. Ohio Sta., 

 1 {1916), No. 7, pp. 199-201). — Data collected in 64 per cent of the counties of 

 the State are reported as showing that 22.7 per cent of the red clover, 22.3 per 

 cent of the mammoh clover, 17.3 per cent of the alsike clover, and 44 per cent 

 of the alfalfa winterkilled during the winter of 1915-16. Grimm alfalfa was 

 found to show no greater resistance to winter conditions than common alfalfa 

 from seed produced in the Northwestern States. 



Comparative yields of hay from several varieties and strains of alfalfa at 

 Brooking'S, Highmore, Cottonwood, and Eureka, A. N. Hume and M. Champ- 

 LiN {South Dakota Sta. Bui. 163 {1916), pp. 282-343, figs. 9).— Historical and 

 descriptive notes are given of a number of varieties and strains of alfalfa and 

 other species of Medicago introduced and tested in South Dakota. Results are 

 reported of comparative trials of several varieties and strains of alfalfa made 

 at Brookings, Highmore, Cottonwood, and Eureka. 



The average yield of field-cured hay per acre in the four localities for the 

 three years, 1913 to 1915, was 2,565 lbs. for Vale, 2,532 lbs. for Grimm, and 

 2,527 lbs. for Turkestan alfalfa. It is not implied that these three strains 

 should be produced to the exclusion of all others, but it is advised that such 

 strains as Baltic S. D. No. 167, Common S. D. No. 12, Kansas Nonirrigated S. D. 

 No. 173, and other strains now successfully grown in the State should not be 

 hastily discarded. Attention 5s called to the fact that although Turkestan 

 alfalfa is adapted to hay production in South Dakota, the seed of the variety 

 has a much more limited market outside of the State than the seed of other 

 strains. Field trials of strains of Medicago falcata made at Brookings are re- 

 ported as indicating that the species luay not yield as large average amounts 

 of hay as the strains of M. sativa which have been tested. 



