in] POTASSIC MANURES 29 



the live weight increase in sheep, was higher, so that on the whole 

 the slag came out the better. In the Aberdeen experiments 

 there was little to choose between them, but the largest crops were 

 obtained from a mixture of the two. 



There has been a good deal of discussion as to whether high 

 grade or low grade slags are most economical and what degree of 

 solubility in citric acid is desirable. Experiments on these points 

 are still in progress. 



Bones. The various bone manures are very popular, but on 

 the whole they have not proved as successful as superphosphate 

 for turnips, or as slag for grass. Steamed bone flour is useful in 

 dry situations, while bone meal has proved useful for potatoes in 

 the place of superphosphate. There is no justification for paying 

 any fancy price for bone manures, but they may come in very 

 handy in case of shortage. 



Mineral and patent phosphates. Some of these have proved 

 distinctly useful, though not equal to superphosphate or slag. 

 They should be offered at a low price, but as they are very 

 variable in nature they should only be used on expert advice. 



3. POTASSIC MANURES. 



Potassic manures are wanted: 



1. For potatoes, mangolds and leguminous crops. 



2. On other crops when extra vigour is wanted, e.g. when 

 diseases occur. 



3. On light sand or thin chalk soils. 



But as they cannot be obtained now, the main question is how 

 to do without them. 



There are two ways : to use other sources of potash instead of 

 the ordinary Stassfurt salts, and to make fuller use of the potash 

 supplies already in the soil. 



Sources of potash other than the Stassfurt salts. 



Various ashes, etc. Every farmer obtains a certain amount of 

 potash on his own farm in the course of the year, and it is very 

 desirable that some of this should be saved. The ashes of hedge 

 trimmings contain up to 10 per cent, of potash, nearly the same 



