XI.] MANURES FOR SWEDES 315 



the seed and superphosphate are sown from the same 

 drill on the top of the ridge. This plan answers 

 excellently in the cooler and moister parts of the 

 country, where the Swede flourishes and grows big 

 crops, but in the south and east of England such a 

 method exposes the crop too much to risk of damage 

 from drought, both through evaporation from the sides 

 of the ridge and because the fresh manure as it rots 

 leaves the land too open. On warm dry soils it is better 

 to plough in the farmyard manure in the autumn, and 

 to sow the Swedes on the flat with their appropriate 

 artificial manure. It is in the south again that farm- 

 yard manure is often lacking for the Swede crop, because 

 it has been wanted for wheat or hops or potatoes, or 

 sometimes for the grass land ; many sheep farmers, 

 again, who fold on the Swede land have a strong 

 objection to Swedes grown with farmyard manure. A 

 suitable mixture in this case, when no farmyard manure 

 is available, will consist of 4 cwts, of superphosphate 

 (or its equivalent in basic slag or steamed bone flour 

 as before), 2 cwts. of fish or meat guano, and \ cwt. of 

 a mixture of nitrate of soda and sulphate of ammonia 

 as a top dressing when the plants are singled. If the 

 land is in really good heart, the fish guano can be 

 omitted or reduced. It will be seen that various com- 

 pounds of nitrogen are used in order to ensure a steady 

 and continuous supply of nitrates as long as the plant 

 is growing ; the mixture of sulphate of ammonia and 

 nitrate of soda ensures a neutral reaction in the soil. 

 Though superphosphate and sulphate of ammonia are, on 

 the whole, the best fertilisers in their respective classes 

 for Swedes, they must be employed with care where 

 there is little lime in the soil, and not at all if the land 

 is known to be subject to " finger-and-toe." Both are 

 acid manures, and the organism causing finger-and-toe 



