l8 MAINE AGRICULTURAL EXPERIMENT STATION. 



pie the droppings from looo birds, if preserved without need- 

 less loss, will be worth at least $300. 



Poultry manure contains more nitrogen than other farm 

 manure, because in birds the excretion of the kidneys is voided 

 in solid form (uric acid), with undigested portions of the 

 food. This form of nitrogen is easily available to plants. 

 Unfortunately, however, it is not stable. Putrefactive processes 

 easily change it to ammonia compounds, and unless special 

 care is taken of the droppings one-third to one-half of the 

 nitrogen passes off as ammonia gas. 



The mechanical condition of poultry manure is poor. It 

 is apt to be sticky when fresh and lumpy when dry. On this 

 account, if used untreated, it can only be successfully applied 

 to the land by hand, as it does not work well in drills or spread- 

 ers. Hen manure used alone is very wasteful of nitrogen as 

 it carries this element in too large a proportion to its phos- 

 phorus and potassium. 



In the experiments referred to above the attempt was made 

 to find a method of treatment of hen manure which would first 

 prevent the loss of nitrogen, second, add. sufficient phosphorus 

 and potassium in forms available for plant food to make a 

 balanced fertilizer; and, third, so improve the mechanical con- 

 dition of the dung that it can be applied to the land with a 

 manure spreader. Seven different methods of treatment were 

 tested. Summarized the results were as follows : By itself, 

 hen dung is a one-sided nitrogenous fertilizer. As usually man- 

 aged, one-half or more of its nitrogen is lost, so that as ordi- 

 narily used it does not carry so great an excess of nitrogen. 

 Because of its excess of nitrogen it will be much more econom- 

 ically used in connection with manures carrying prosphoric 

 acid and potash. As both acid phosphate and kainit prevent 

 the loss of nitrogen, it is possible to use them in connection with 

 sawdust or some other dry material as an absorbent (good dry 

 loam or peat will answer nicely) so as to make a well balanced 

 fertilizer. For example, a mixture of 30 pounds of hen ma- 

 nure, 10 pounds of sawdust, 16 pounds of acid phosphate, and 

 8 pounds of kainit would carry about .25 per cent nitrogen, 4.5 

 per cent phosphoric acid, and 2 per cent potash, which, used at 

 the rate of 2 tons per acre, would furnish 50 pounds nitrogen, 

 185 pounds phosphoric acid and 80 pounds potash. 



