EXPERIMENTS IN FIELD TECHNIC IN PLOT TESTS ' 



By A. C. Arny, Head of Section of Farm Crops, and H. K. Hayes, Head of Section of 

 Plant Breeding, Division of Agronomy and Farm Management, Department of Agri- 

 culture of the University of Minnesota ^ 



INTRODUCTION 



In summarizing the replies to a circular letter sent out to Experiment 

 Stations in the United States and in Canada, one is impressed with the 

 wide variations in the size and shape of the plots and in the width of 

 alley between plots in variety, cultural, rotation, and fertility work. 

 The general size of plots varies from y|^ to yi acre and in shape from 

 3 to 33 feet wide and 36 to 272.25 feet long. The width of alley between 

 plots varies from none to 8 feet. Twenty-two Stations report the 

 removal of end borders from plots, and nine report no alleys, mth grain 

 removed to form pathway or the removal of one side border drill row 

 from either side of each plot. 



This lack of uniformity in experimental technic in plot tests, particu- 

 larly with regard to alley effect, which involves shape and size of plot, 

 raises several questions, among which are the following: 



(i) How far within plots is alley effect operative? 



(2) What is the increase in yield due to alley effect? 



(3) In plots surrounded by alleys, is the effect of the additional space 

 the same on all varieties? 



Data obtained at University Farm in 191 7 from which to determine 

 the most desirable methods in plot variety testing and cultural trials 

 form the basis of this paper. Although the results are for one season 

 only, they appear to be sufficiently conclusive to warrant their publica- 

 tion. It is hoped that similar work may be done elsewhere, and the 

 collected data serv^e as a basis for the adoption of more uniform methods 

 in plot tests. 



REVIEW OF LITERATURE 



Montgomery (d)^ suggests two methods of obviating competition 

 between the larger and more rapidly growing varieties of wheat and oats 

 grown in 8- and lo-inch rows — namely, to plant only similar varieties 

 in adjacent rows and the use of block plots. The possible effect on the 



' Published, -with the approval of the Director, as Paper 124 of the Journal Series of the Minnesota Agri- 

 cultural Experiment Station. 



2 The authors wish to acknowledge their appreciation of the assistance given by Mr. R. J. Garber, Assist- 

 ant in Farm Crops, in compiling the data. 



5 Reference is made by number to " Literature cited," p. 270. 



Journal of Agricultural Research, Vol. XV, No. 4 



Washington, D. C. Oct. 28, 1918 



py (251) Key No. Minn.-34 



78776—18 3 



