302 CAUSES OF FERTILITY AND STERILITY [chap. 



ment. A very successful experiment of this type has 

 been made on some 200 acres of the " brek " land 

 at Methwold in Norfolk, land which was covered with 

 bracken and had never previously been cultivated. In 

 the second year after breaking up the land was yielding 

 27J bushels per acre of wheat and 28 of oats, and 

 within the first five years of the trial the initial 

 expenses of reclamation, amounting to between .5 

 and 6 per acre, had been repaid by the profits on the 

 crops. 



The financial results have been published, but 

 as both the cost of the work and the value of the crops 

 are abnormal owing to the war years, it is sufficient 

 here to draw the conclusion that land worth only 

 2s. 6d. to 5 s. an acre for sporting purposes has been 

 given a letting value of 15s. an acre by an initial 

 expenditure of about 6 an acre. The soil was one of 

 the coarsest of sands and the rainfall in the district 

 among the lightest in England. 



Paring and Burning. 



When the poorer clay soils were first taken into 

 cultivation, a beginning was generally made by " paring " 

 the surface with the breast plough, and "burning" the 

 clods as soon as they were sufficiently dry. The clods 

 were made up into heaps a yard or so in diameter, with 

 the brushings of the hedges and all the rough surface 

 vegetation, together with as much clay as was judged 

 prudent. Each heap was then allowed to burn slowly 

 and char the clay, without permitting the heat to rise 

 sufficiently to vitrify the clay or dissipate such valuable 

 material as the alkalis of the ash. The resulting ashes 

 effected a great improvement in the soil : the clay was 

 partially dehydrated, or at least coagulated, thus pro- 

 viding a certain amount of coarse material to ameliorate 



