174 MASS. EXPERIMENT STATION BULLETIN 155. 



this application should be supplemented by 500 pounds of basic 

 slag phosphate. Some of the commercial sheep manures, par- 

 ticularly those from wool-carding establishments, often carry 

 large quantities of noxious weed seeds. 



Wool Waste extracted of Grease (Sud Cake) {No. 2). — 

 This product would be more suitable for corn and to fit land 

 for seeding to permanent meadows than for potatoes or other 

 hoed crops. It can be used to advantage on all soils deficient 

 in organic matter and humus. Five tons per acre may be used 

 to good advantage for corn or seeding to grass. In addition 

 it would be well to use 150 pounds of muriate of potash and 

 500 pounds of basic slag phosphate. 



No. 3. Fine-gi'ound Foreign Whale Guano. 



No. 4. Roekweed. 



No. 5. Crude Un ground Garbage Tankage. 



Analysis. 



Fine-ground Foreign Whale Guano (No. 3). — Whale guano 

 is quite similar in composition to dry ground fish. Its nitrogen 

 availability is probably about 67.50 per cent., while that of 

 fish averages about 70 per cent. The whale guano carries quite 

 a high percentage of fat (13.82 per cent.), which will probably 

 prevent its nitrogen from becoming as quickly available as that 

 in fish scrap. 



Eocl'iveed {No. J/-). — Eockweed may be used broadcast at 

 the rate of 5 to 6 tons per acre, and thoroughly worked into 

 the soil by means of a disk harrow. The use of lime with this 

 material will ordinarilv be found advantageous, — from one- 



