432 THE WHEAT PLANT 



In spite of the fact that under special circumstances thin-sowing may 

 succeed, in practice it is found to be less hazardous to attempt to obtain 

 an adequate number of ears per acre by thick-sowing rather than by thin- 

 sowing and its concomitant tillering, especially when the amount of seed 

 sown is far removed from that ordinarily sown. 



Proportion of Grain to Straw and Proportion of Grain to Chaff. The 

 ratio between the weight of the grain and that of the straw of the wheat 

 plant varies very much with the variety, the space allotted to the plants, 

 and their nutrition. 



As ordinarily grown in the field the average proportion is usually 

 32-36 per cent of grain to 68-64 P er cent f straw, but large amounts of 

 farmyard manure or nitrogenous fertilisers stimulate the production of 

 leaves and stems and reduce the proportion of grain to straw. 



Plants grown at wide intervals show a different ratio. 



Of seventeen common forms of Bread Wheat grown in rows i foot 

 apart, the plants 6 inches asunder in the rows, the highest proportion 

 was 47 per cent of grain to 53 per cent of straw, the lowest 33 of grain 

 to 67 of straw. 



The proportion of the weight of the grain to that of the rest of the ear 

 (chaff and rachis) in a beardless wheat whose ears (500) were selected at 

 random from the field was 66-6 per cent of grain to 33-3 of chaff and 

 rachis, or 2 of grain to i of chaff. 



In ears of plants grown 6 inches apart the proportion of grain was 

 higher, reaching in a number of cases a ratio of 75-78 per cent of grain to 

 25-22 per cent of chaff, i.e. between 3 or 4 of grain to i of chaff. 



