VII] THE RISE OF THE SANDS 113 



When Herr Schultz came into possession in 1855 

 the land was largely a barren heath, yielding crops 

 only at considerable expense. He soon observed, 

 however, that lupins grew well provided the rainfall 

 was sufficient (the average fall was 27 inches), and 

 also found that they enriched the soil in nitrogenous 

 organic matter and fertilised the next crop. His 

 method as finally worked out was essentially as 

 follows : leguminous crops were gi^own and fertilised 

 with mineral manures — lime, phosphates and potas- 

 sium salts — in order to induce considerable plant 

 development and therefore considerable nitrogen 

 fixation. Some of the crops were cut for hay, but 

 in the main they were ploughed in, thus adding to 

 the soil the nitrogenous organic matter of the stems 

 and leaves as well as of the roots. Crops thus 

 ploughed in are called green manure. An acre of 

 green crop was found to furnish roughly as much 

 nitrogen as 10 to 15 tons of farmyard manure, and 

 this, taken in conjunction with the nutrients added 

 in the artificial fertilisers, sufficed to yield large crops 

 of grain and potatoes. Thus, without purchasing- 

 nitrogenous manures (which are very costly), and 

 without keeping much live stock, Schultz was able 

 by periodical green manuring enormously to increase 

 the productiveness of his land. This extremely valu- 

 able method has been much adopted in Germany. 

 Where high priced crops are grown it may prove 



B. 8 



