1897.] PUBLIC DOCUMENT — No. 33. 195 



6. Field Experiments to ascertain the Influence of 

 Different Mixtures of Commercial Fertilizers 

 ON the Yield and General Character of Sev- 

 eral Prominent Garden Crops. 



The area devoted to the above-stated experiment is 198 

 feet long and 183 feet wide ; it is subdivided into six plats 

 of uniform size (89i by 62 feet, or about one-eighth of an 

 acre each) . The plats are separated from each other and 

 from the adjoining cultivated fields by a space of 5 feet of 

 unmanured and unseeded yet cultivated land. 



They are arranged in two parallel rows, running from 

 east to west. Plats Nos. 1 , 2 and 3 are along the north side 

 of the field, beginning with No. 1 at its west end, while plats 

 Nos. 4, 5 and 6 are located along its south side, beginning 

 with Plat 4 on the west end. The soil is several feet deep, 

 and consists of a light, somewhat gravelly loam, and was in a 

 fair state of productiveness when assigned for the experiment 

 here under consideration. The entire field occupied by the 

 experiment is nearly on a level. Potatoes and a variety of 

 forage crops have been raised upon it in preceding years. 

 The manure applied since 1885 has consisted exclusively 

 of fine-ground bone and muriate of potash, annually, 600 

 pounds of the former and 200 pounds of the latter per acre. 



The observation with raising garden crops by aid of the 

 different mixtures of commercial manurial substances, here 

 under special consideration, began upon plats Nos. 4, 5 and 

 (1 during the spring of 1891, and upon plats Nos. 1, 2 and 3 

 during that of 1892. 



The difl'crence of the fertilizers applied consisted in the 

 circumstance that the different forms of nitrogen and pot- 

 ash were used for their preparation. All plats received 

 essentially the same quantity of nitrogen, potash and phos- 

 phoric acid, and every one of them received its phosphoric 

 acid in the same form, namely, dissolved bone-black. Some 

 plats received their nitrogen supply in form of organic animal 

 matter, dried blood ; others in form of sodium nitrate. Chili 

 saltpetre ; others in the form of ammonium sulphate. Some 

 plats received their potash in the form of muriate of potash 



