43 



found in his garden a single plant bearing 80 ears, which yielded 4524 

 grains, and I have had plants bearing 60-70 ears and over 2500 grains. 



Many other examples might be given of the enormous number of 

 grains which can be obtained from the sowing of one. 



In all these examples the plants were grown on soils in a high state of 

 fertility and had unrestricted space for their development. 



The most important limiting factors in these high returns of single 

 plants is the space upon which they are grown, and the extent of the soil 

 through which the roots can freely penetrate without competition from 

 other plants. 



These factors are frequently overlooked in discussing methods of 

 improving the yield per acre by the growth of exceptional plants. 



The necessary space required to secure these highly productive plants 

 is not known, but it is certain that it is vastly greater than 10 square inches, 

 the space which is allotted to each grain when one bushel (650,000 grains) 

 is sown on an acre. 



In the table below, from a single grain sown on the most widely 

 spaced plot 354 grains were produced, and from i bushel of similar grains 

 354 bushels would be obtained ; nevertheless, since each plant was allotted 

 4 square feet, to secure 354 bushels from such plants an area of nearly 60 

 acres would be needed. In other words, the yield is less than 6 bushels 

 per acre, although the statement that the return was 354 grains or bushels 

 for one sown appears exceptionally large. 



Similarly the statements made by some thin-seeding enthusiasts that 

 they had experienced " a return of 500 for i on an acre," and " 804 for i 

 on a plot of 700 square feet," are no indications either of good or bad 

 yields per acre, for the statements apply equally to i grain, i pound, or 

 i bushel sown per acre or plot. 



With increasing space the number of ears per plant and the number of 

 grains in each ear rises rapidly. 



Below are given the results of the growth of plants of Swan wheat (T. 

 vulgare) produced from grains sown at varying distances apart, the smallest 

 space allotted to each plant being 6 square inches, the largest 576 square 

 inches. 



TABLE I 



