728 EXPERIMENT STATION RECORD. 



"These observations show very conclusively that the drying out of coarse, sandy 

 subsoils may take place to so extreme a degree as to almost approach the so-called 

 hygroscopic moisture dryness, no matter how perfect a mulch may be maintained 

 over them, provided the interval between rains is loni; enough. They further show 

 quite as conclusively that the coarse, sandy soils, no matter how inherently rich 

 they may be in plant food, must remain unproductive in all localities where the 

 ground water is not near the surface, unless good showers fall at short intervals or 

 unless the rains are supplemented by irrigation.*' 



The treatment of swamp or humus soils, F. H. King (Wisconsin 

 Sta. Rpt. 1897, pp. 232-239, figs. 10). — This is a continuation of previous 

 experiments (E. S. R., 9, p. 536) on recently reclaimed swamp land. In 

 the earlier experiments with corn little or no increase of yield was 

 observed where commercial fertilizers had been applied, but there was a 

 very decided improvement where barnyard manure had been used. Oats 

 and barley following the corn derived decided benefit from the barn- 

 yard manure applied the previous year, but none from the commercial 

 fertilizers so applied. Plats which had produced a uniformly good 

 crop of corn in 1896 gave very irregular yields in 1897. Experiments 

 were made in the plant house with soils taken from spots Avhich had 

 given good crops as well as from those on which the crops were poor. 

 The pots used in these experiments were galvanized-iron cylinders 3 

 ft. in diameter and 4 ft. 4 in. deep, and held 2,200 lbs. of soil. Twenty- 

 four of these pots were devoted to corn, 4 to oats, and 8 to clover, one- 

 half in each case being filled with productive soil, the other with 

 unproductive soil. 



" In 4 of the cylinders planted to corn the soil was put in as loosely as possible, in 

 order that it might be better aerated, while in all the others the soil was closely 

 packed to imitate the held conditions. With 4 other cylinders cut, dry straw was 

 worked into the surface 8 in. of the soil with a view to better aerating it by another 

 method which might be presumed to imitate the conditions produced by the grass 

 turned under with the hrst plowing of these fields, and also the mechanical effect of 

 farmyard manure. Four other cylinders were given a dressing at the rate of 30.8 

 tons of farmyard manure per acre, both for better aeration and to supply new mate- 

 rials from which nitrates might be developed. Another 4 cylinders were given a 

 dressing of sodium nitrate at the rate of 400 lbs. per acre, in order that available 

 nitrates might be present to start with. Still another 4 were given potassium car- 

 bonate at the rate of 400 lbs. per acre, while the remaining 4, planted to corn, were 

 given nothing and held as a check upon the first 4 which had the loose soil, these 

 being filled with the firmed soil and presumably not so well aerated." 



Three crops of corn in succession have been planted in these cylin- 

 ders. In case of the first crop the yield was best on the manured 

 cylinders. The yields on the cylinders receiving potash and cut straw 

 stood next, the crop being equally benefited by these 2 materials. No 

 benefit was derived from the nitrate applied. The yields were no bet- 

 ter on the loosely packed soil than on the firmly packed soil. 



"In the case of the second crop of corn the manured cylinders are decidedly ahead, 

 while the cut straw, nitrate, -and potash cylinders are about equally improved over 

 the 2 sets of untreated cylinders, which again are about alike and show nothing 

 gained or lost by the loose packing. . . . 



