Food for Conditions of the Experiments. 



Plants 



92 



\Y/h H R ^°^ many years the Rhode Island Agricul- 

 w nat riaS occn i r* • c .• i ■ i 



T^ . tural r^xperiment Station has carried on a 



Proven in . r i ^ ^ ^ a .u u u • c 



T^, , T 1 J series or plat tests ; and the behavior or 



Rhode Island. ^, i ^ ^u r .u i . r 



the hay crop on three or these plats tor 



four successive years has thrown much light upon the 



problem of maintaining the fertility of our pastures and 



meadows. 



Up to the year 1893 the treatment of these plats, for 

 many years, had been identical. From 1893 ^° 1898 the 

 plats received annually the same amounts of phosphoric 

 acid in the form of high-grade phosphate and of potash as 

 muriate. One plat received no Nitrogen during this time 

 and probably had received none for from fifteen to twenty 

 years; the second plat was given annually, early in the 

 spring, an application of Nitrate of Soda at the rate of 150 

 pounds to the acre; and the third plat received three times 

 as much Nitrate, 450 pounds to the acre. 



All the plats were used for the growth of leguminous 

 crops during most of this period. In 1897 all the plats 

 were sown to barley and were treated with air-slaked lime to 

 correct the acidity or " sourness," which is a characteristic 

 of much of the soil of Rhode Island. 



On April 23, 1898, the plats were again sown to barley 

 and seeded down with a mixture of seeds, — red clover and 

 red top, j}4 pounds each, and timothy 15 pounds. 



The fertilizer applications were continued as before, — 

 equal quantities of phosphoric acid and potash'^' on all plats, 

 no Nitrogen on one, J/3 ration of Nitrate of Soda on the 

 next and full ration of Nitrate on the third. These 

 materials were all applied broadcast as a top-dressing early 

 in the spring. 



Effect of Nitrate on Yields. 



Since all the other fertilizers were alike for the three 

 plats and had been for many years, and since the general 



* The amounts of phosphoric acid and potash varied from year to year ; of phosphoric 

 acid the actual weights per acre were 164, 191, 130 and 130 pounds for the successive years j 

 of potash, 883^, 90>^, 100 and 150 pounds. 



