Manures and Manuring 21 
is a profitable form of phosphatic manure to use, as it not 
only supplies the crops with phosphates, but also supplies 
lime to the soil, and we have already pointed out the 
value of lime to a heavily manured ground. Now, from 
what we know about these phosphatic manures, we can 
form an idea of the method of their application. We 
know that superphosphate is quick -acting, therefore it 
should be applied about the time it is required for the 
use of the plant as food. That is, it should, as a rule, 
be applied in spring, and at the rate of from 3 to 5 lb. 
per pole. 
The various bone manures should be used at the rate 
of from 5 to 10 lb. per pole. 
Basic slag, being slow in action, should be applied in 
winter, at the rate of from 5 to 10 lb. per pole. Nearly 
all crops benefit by the application of phosphates, more 
especially fruit crops. Their action is not so apparent as 
that of nitrates, but is quite as beneficial. 
POTASH 
This is a most valuable manure, but its use must be 
thoroughly understood before being applied, as consider- 
able damage may be done if it is used improperly. Many 
soils contain sufficient potash for the use of the crops, 
but it is often found in such a form as not to be available 
for use as food. Again, there are certain crops which take 
a greater amount of potash out of the soil than others. 
It is then necessary to supply it in such a form as can 
most readily be used. Potatoes, Beet, and Carrots require 
a great amount of potash. Fruit also requires a consider- 
