4 i 8 THE WHEAT PLANT 



ment has been made in this sense during the last half century or more in 

 this country. There is much evidence that most of the good land was 

 highly farmed seventy to a hundred years ago, and rarely gave less than 

 40 bushels per acre. 



Moreover, in Great Britain the higher and lower limits of yields per 

 acre during the last hundred and fifty years or more appear to have been 

 much the same, records of 50 and 60 bushels per acre are frequent as far 

 back as the middle of the eighteenth century, and Bradley in 1757 states 

 that " the largest produce of an acre of wheat land, so far as has yet been 

 experienced, seems to be 10 quarters or 80 bushels per acre," a yield which 

 is rarely equalled at the present day. 



Norden in 1607 observes that in Somersetshire on well-tilled good 

 land " they have sometimes in some places 4, 5, 6, 8, yea, 10 quarters in 

 an ordinary acre." 



The largest yield per acre hitherto recorded in any part of the world 

 upon a field of more than i acre is 117-2 bushels, which is given in the 

 United States Monthly Crop Report for July 1918. The crop was grown 

 in 1895 on a field of 18 acres in Island County, Washington, U.S.A., the 

 soil being described as a black sandy loam overlying a clay subsoil. The 

 variety of wheat was Australian Club. No manure had ever been applied 

 to the land, and in the three previous seasons potatoes were grown on the 

 field. 



In 1918, Mr. Alfred Amos of Wye, Kent, obtained a yield of 96 

 bushels (63 Ibs.) per acre of " Yeoman " wheat on an area of about 3^ acres. 

 The seed was sown on November 20, 1917. The soil of the field is a 

 deep rich loam overlying 6 feet of brick earth. No fertiliser was applied 

 to the wheat crop, but the previous crop of beetroot was well manured. 



Morton (Journ. Royal Agric. Society, 1859) reports a yield of 90 bushels 

 per acre obtained in 1844 on a field measuring 5} acres in the parish of 

 Haisborough in Norfolk. 



The wheat grown was " Spalding," sown in the autumn of 1843 at 

 the rate of 3 bushels per acre. 



Land almost adjoining gave 80 bushels per acre in the same season. 



The lower limits of the yield of wheat as ordinarily grown in Great 

 Britain are 10 or 12 bushels per acre, returns of this amount being not 

 infrequent during the last hundred and fifty years. 



The yield per acre is dependent upon a very large number of factors. 

 Some of them cannot be altered by the farmer, while others are within 

 his power to modify and control. 



To the former class belong climate, season, and original physical and 

 chemical condition of the soil ; among the latter are drainage, cultivation, 

 and manuring of the soil, the yield per ear and the number of ears grown 

 per acre. 



