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MISSOURI AGR. EXP. STA. RESEARCH BULLETIN 49 



Kiesselbach 5 ' T has published rather extensive data on the compe- 

 tition between adjacent rod-rows. In his experiments the crops were 

 compared in alternating single-row plots and in alternating 5-row 

 blocks, each replicated fifty times. In some cases the border rows of 

 5-row plots were discarded. The deviation of the result in the test 

 in single-row plots from that of the test in 5-row plots is regarded as the 

 measure of the effect of competition. The comparative yields of va- 

 rieties of wheat and oats in alternating single rows and in alternating 

 5-row plots are shown in Table 9, from Kiesselbach 7 . 



9. RELATIVE YIELDS OF Two SMALL GRAIN VARIETIES WHEN COMPARED 

 IN ALTERNATING Rows AND IN ALTERNATING 5-Row PLATS (KIESSELBACH). 



*Yield based on 3 inner rows of 5-row plats in 1914. 



Kiesselbach also submits interesting data on the competition of 

 pure line selections of the same variety. It might be supposed that 

 such strains, being similar in varietal characteristics, would be little 

 affected by competition, and could therefore be safely compared in 

 single-row plots. The average relative yields of three strains of Turkey 

 wheat in single rows and in blocks for two seasons, however, showed 

 that the two better strains were favored approximately 20 per cent and 

 15 per cent, respectively, at the expense of the poorer strain, in the 

 single-row test. A strain which yielded 26 per cent more than an- 

 other in the single-row test yielded only 6 per cent more in the block 



