FOEEST GROWTH. 55 



to mangels, generally produces a great effect on the crop ; 

 this is not the case with turnips, which require phosphates 

 as well as nitrogen in their manure. 



As both turnips and mangels consume extremely large 

 amounts of plant food, a liberal general manuring with 

 fsr*myard manure is in most cases essential for the pro- 

 duction of a full crop ; but the special characteristic of 

 the manure for turnips should be phosphatic, and of that 

 for mangels nitrogenous. With an abundant supply of 

 nitrogenous manure the proportion of leaf is increased, 

 and the maturity of the root delayed. A heavily manured 

 crop should be sown early. Late-sown crops of turnips 

 or swedes should receive a smaller proportion of nitrogen, 

 and a larger proportion of phosphates in their manure. 



When beetroot is grown for sugar it is essential to 

 produce small roots; heavy manuring is therefore 

 avoided, and the roots grown near together. 



Potatos are surface feeders, and require a liberal 

 general manuring to ensure an abundant crop. 



As both root crops and potatos require large supplies 

 of potash, kainite will be found of service on land naturally 

 poor in that ingredient. It will be chiefly required when 

 the crops are raised with artificial manures only, as farm- 

 yard manure will always supply a considerable amount of 

 potash. 



Forest Growth. The figures given in the table re- 

 present the composition of the produce of beech, spruce 

 fir, and Scotch pine forests felled for timber, and are the 

 results of extensive investigations made in Bavaria. 



The amount of dry matter in the annual forest growth 

 is in excess of that yielded by any of the cultivated crops 



