shape; and size of plots in tests of varieties of grain. 



79 



From Table 2 it is evident that a rectangular unit area in the 

 form of a square possesses the shortest periphery and therefore 

 presents the smallest number of plants along its borders. As 

 shown in this table, a change in the shape of a unit area, for 

 example, in the case of its elongation to a length sixteen times 

 its width may subject as many as 112.5 per cent more plants, as 

 compared with those of the same unit area in the form of a 

 square, to the influences arising from miarginal conditions. An 

 increase in the length of a plot increases the number of plants 

 along the margin. 



What has been said here holds true for plots sown broadcast, 

 as well as for those seeded in drills. Each unit within the mar- 

 gins of a broadcasted plot supports, according to the laws of 

 cbance, a number of plants numerically equal to those of every 

 other unit of the plot. The same is true in drilled plots. A 

 plot in which seed is sown in drills six inches apart is divided 

 into equal areas six inches wide. Each of these receives on the 

 average the same number of seeds and supports equal numbers 

 of plants according to the laws of chance. Hence an area six 

 inches wnde within the margins of a plot contains the same 

 number of plants as an equal area within the plot. It should 

 be pointed out here that a circular plot of a unit area has the 

 shortest periphery and therefore presents the smallest number 

 of plants along the border. However, the impracticability of 

 seeding and handling plots of this shape is obvious. 



Table 3. 



The Relation of an Area Six Inches Wide Within the Border 



of a Plot to the Total Area of the Plot. 











4A 











fi ra 





c 







•?^c 















c 



. 





Size of Plot. 



"o 





rr- 



^'^S 







S.S 









p, 



w a 



K- 2 = 





s 



c a 



C'C 



0-C43 







Q'o 



a 



<s.a 



3 "3 ° 

 3 ^-^ 



2000th acre 



1000th acre 



Square ........ | 4 . 67x4 . 67 



Length 2 times I [ 



width I 3 . 30x6 . 60 I 



Length 4 times , j 



•width 2.33x9.33 



Square 6.60x6.60' 



Length 2 times 



width 4 . 67x9 . 33 



2.S'S S 





Ph.£ 



18.67 



8.33 



38.26 



19.80 



8.90 



40.86 



23.33 

 26.40 



10.67 

 12.20 



48.98 

 28.01 



28.00 



13.00 



29.85 



6.79 

 28.00 



