80 



BULLETIN 699, U. S. DEPAKTMENT OF AGEICULTURE. 



Table XLVI. 



-Average yields of corn, oats, wheat, clover, and cotopeas in an 

 8-year experiment at Laclede, Mo. (1907-191Jf). 



Fertilizer. 



Application per acre. 



Com, 

 6 crops. 



Oats, 

 6 crops. 



Wheat, 

 6 crops. 



Clover, 

 2 crops. 



Bushels. 

 32.6 



1 39.1 



Bushels. 

 28.3 

 35.3 



Bushels. 

 14.4 

 16.9 



Pounds. 

 2,970 

 4,540 



i 43.3 



37.3 



16.2 



4,650 



i 46.1 



40.3 



19.9 



4,940 



36.1 



47.2 



32.7 

 35.6 



13.1 

 14.9 



3,425 

 3,104 



} •" 



35.1 



14.5 



3,560 



I 45.8 



35.0 



14.3 



3,670 



Cowpeas, 

 4 crops. 



Legume 



Do 



Bone meal 



Legume 



Bone meal 



Lime 



Legume 



Bone meal 



Lime 



Potassium chloride. 



No treatment 



Manure 



Do 



Rock phosphate 



Manure 



Rock phosphate. . . 

 Legume ; . . 



150 pounds 1 



150 pounds • 

 1 ton2 



150 pounds ' 



1 ton2 



50 poundsi . 



8 tons 3 



8 tons 3 



500 pounds < . 



8 tons 3 



500 pounds * . 



Pounds. 

 2,727 

 3,377 



3,604 



3,582 



2,396 

 2,637 



3,116 

 3,277 



1 Applications made every two years. 



' Applications made every eight years. 



» Applications made every four years. 



< Applications made every four years, but in 1913, the rate was inceased to 1,000 pounds per acre. 



The results obtained on the Laclede field are in a general way 

 similar to those obtained at Hurdland, namely : The reenf orcement of 

 manure with phosphate rock apparently had little influence on the 

 former's effectiveness, except in the case of the clover and cowpea 

 crops. On the other hand, plots treated with bone meal in connec- 

 tion with a legume produced considerably better average yields of all 

 crops than plots receiving the legume treatment only. 



As in the case of the three previous experiments, however, no strict 

 comparison between the bone and raw rock phosphate plots is pos- 

 sible, and since the yields of the various crops in the individual years 

 are not given, the residual effect of the phosphate treatments can not 

 be determined. 



Four out of five field experiments with raw rock phosphate con- 

 ducted by the Missouri Experiment Station cover a period of over 

 five years. Two out of the four experiments reported in detail show 

 increases resulting from the liberal use of raw rock phosphate in 

 connection with organic matter. The other two show little or no 

 benefit from applications of this material. No attempt was made in 

 any of these experiments to compare the fertilizer value of raw rock 

 and acid phosphate. 



NEW JERSEY. 



The first work of the New Jersey Experiment Station* on raw 

 rock phosphate consisted of a series of cooperative experiments con- 

 ducted by farmers in different sections of the State. Most of the 

 experiments were conducted for one year only, and while several 



» N. J. Agr. Expt. Sta., 6th, 7th, 8th Ann. Repts. 



