i9 1 1.] Cost of Producing Wheat, etc., in U.S. 655 



suffering from toxicity. Again, wheat has been grown con- 

 tinuously in the Broadbalk field at Rothamsted for sixty 

 years, but so far there is no sign that the plot is suffering from 

 the presence of any toxic substance. 



It must be admitted that the investigations of the Bureau 

 of Soils have served a useful purpose in directing attention 

 to factors of fertility other than the chemical composition of 

 the soil. Physical conditions undoubtedly play a more 

 important part than the earlier chemists were disposed to 

 assign to them, but investigation on fertility cannot be 

 restricted to chemical and physical conditions : the biological 

 changes which go on in the soil must be investigated, and 

 these again cannot be restricted, as they have been hitherto, 

 to the bacterial flora. As Dr. Russell's work on soil sterilisa- 

 tion demonstrates, higher forms of life are probably at work, 

 and may exercise a profound influence on plant growth. 



An estimate of the cost of producing cereals in the 

 United States in 1909 has been made by the Bureau of 



Statistics of the United States Depart- 

 Cost of Producing rnent of Agriculture. The estimate is 

 Wheat, Oats and Maize based on the replies received from about 

 in the United States. 5,000 correspondents of the Bureau of 



Statistics, who were asked to supply 

 information on the following points: — Cost per acre of 

 (1) commercial fertilisers, (2) preparing ground for seed, 

 (3) seed, (4) planting, (5) gathering or harvesting, (6) pre- 

 paring for market, (7) wear and tear on implements, (8) rent 

 of land or interest on its value, (9) other items of cost, 

 (10) total cost, (11) average yield of product per acre, (12) 

 value per bushel, (13) value of crop per acre (not including 

 bye-products), (14) value of bye-products, (15) average size of 

 fields in acres, (16) average value per acre of land growing the 

 crop. 



The cost of the labour, both manual and of animals, 

 whether owned or hired, was estimated upon the basis of the 

 prevailing rate of wages paid, whether the actual work were 

 done by the owner or hired labour. The cost of preparing 



