CONTRIBUTIONS FROM THE WISLEY LABORATORY. 93 



the roots, while in the second (fig. 42), where the plants were older 

 and larger, the roots outweigh the foliage. 



The total weight of the turnips (with foliage) from the fifteen 

 plots in Series I. was 1651 lb., from the forty-four plots in Series II. 

 3,338 lb. 



The figures and diagrams make perfectly clear the detrimental 

 influence exercised by close planting upon yield, even when the 

 planting is done at what is regarded as the normal distance. 



It is also clear that when comparisons are being made between 

 yields of varieties, the plots (or rows) must be arranged so that none 

 of the rows (or plants) to be compared has an advantage of space over 

 its fellows. Perhaps the best method of estimating yield is to discard 

 all plants on the outside of the plot, whether forming an outer row 

 or placed at the end of a row. 



