MANURES 37 



ing plants of cabbage, corn, lettuce, etc., provided it is 

 spread out evenly and does not come in contact with the 

 roots of the plants. 



Ground blood is very rich in nitrogen and is quite 

 difficult to dry thoroughly. If it is at all moist it is likely 

 to heat badly. It is a quick-acting fertilizer, and is seldom 

 used without being mixed with other materials. 



Ground bone is rich in phosphoric acid ; but fresh bones 

 are better for this purpose than dry bones, since in addi- 

 tion to phosphoric acid they have quite a large percentage 

 of nitrogen, which is very small in amount in bones that 

 are old and dry. It is always best to grind fine the bones 

 that are to be used on the land, and in many cases to then 

 mix them with fermenting stable manure. Ground bone 

 is said to be a lasting fertilizer because its effect can be 

 seen for several years. If bones are burned the nitrogen 

 is wasted. If fresh bones are mixed with unleached wood 

 ashes they will be made soft so as to be easily broken up. 

 It is generally applied in much the same way and for the 

 same purposes as tankage. 



Nitrate of soda, called also Chili saltpeter, is imported 

 from Chili. It looks like common salt, and contains about 

 16 per cent of nitrogen that is perfectly soluble and in 

 form most available for the plant. On this account only 

 very small quantities should be applied at one time, because 

 if not taken up by the plant it may be washed deep into 

 the soil out of reach of the roots. It is especially desirable 

 for early leaf crops such as early spinach, cabbage, and 

 lettuce, and to apply when a crop comes to a standstill. 



Nitrate of soda acts with wonderful quickness almost 

 like magic. It may be applied several times to the growing 

 crop at intervals of two weeks, using from 75 to 100 pounds 

 per acre at each application. It may be sown near the 



