Oct. .s. igis Expcrimoits in Field Tcchnic in Plot Tests 261 



SUMMARY 



(i) In plots made up of 6-inch drill rows of oats, wheat, and barlev with 

 18-inch alleys between each two, the outside border rows yielded S3. 5, 

 100.4, and 123.3 per cent, respectively, higher than the average from the 

 central 13 rows. For oats, wheat, and barley the inside border rows 

 (second drill rows within the margins of plots) yielded 22,.22>, 49.29, and 

 50.36 per cent, respectively, higher than the averages for the central 13 

 rows. Alley effect is operative over an area at least 12 inches wide 

 \\"ithin the margins of plots. 



(2) The extent of increase due to alleys varies with the percentage of 

 total area in at least a 12-inch strip within the margin of the plots. 

 This percentage is greater for small plots as compared with larger ones 

 of approximately the same shape and for long, narrow plots as compared 

 \\\\h those more nearly approaching the form of a square. 



(3) Plots 6 to S feet wide and 64 to 132 feet or more in length are more 

 easily sown and harv^ested with the ordinary farm machinerv than plots 

 of the same size, but more nearly approaching the form of a square. 

 Removal of the plants occupying an area at least 12 inches in width in 

 comparatively long, narrow plots apparently obviates the most serious 

 objection to their use in variety test work. 



Oats, wheat, and barley, grown in plots 8.5 feet wide and 132 feet long 

 after the end borders had been cut but with no side borders removed, 

 yielded 9.14, 5.28, and 8. 48 bushels more, respectively, than when two 

 side border drill rows had been removed before har^-est. With only one 

 side border row removed from either side of each plot before har\'est, the 

 oat varieties yielded 2.20 bushels, the wheat 1.99 bushels, and the barley 

 2.86 bushels higher than when two drill rows had been removed. 



(4) In a test of oat varieties in plots with two border rows removed, the 

 rank in yield was not the same as when no border rows were discarded. 

 The performance of one variety was very satisfactory by the former 

 and indifferent by the latter method of test. 



The indications are that the barley varieties gro\\Ti in plots surrounded 

 by alleys were not equally efficient in utilizing the additional adjacent 

 space. 



The removal of one or two side border drill rows in the wheat varie- 

 ties did not bring about any significant changes in rank. 



CONCLUSIONS 



In plots surrounded by alleys plants occupying an area at least i foot 

 within the margins are afifected by the additional adjacent space. 



The indications are that, unless there is a considerable fluctuation in the 

 response of varieties to border effect, when grown in plots surrounded bv 

 alleys, superior types may not be given their true rank in tests made in 

 plots from which borders are not removed before harvest. 



