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IOWA DEPARTMENT OF AGRICULTURE 



long, and plots of other sizes in proportion. It is advisable to separatR 

 plots by a division strip seven feet wide. A strip of this width will ac- 

 commodate two rows of corn, or one seven-foot drill. 



A satisfactory plan for showing the location of each plot is worked 

 out by setting a stake in the fence row adjacent to the fence, to mark 

 the outside corner of the first plot. The second stake should then he 

 set in line with the corner stake at such a distance as marks off the 

 exact width of the first plot. The third stake should be placed seven 

 feet beyond the second and thus show the location of the division strip 

 between the first and second plots. By following this plan the exact lo- 

 cation of each plot in the series may be shown. 



A diagram drawn to scale on paper, should be made of the field plots 

 which will show the location of the soil under investigation, the exact 

 length and width of each plot, the width of the division strips, and the 

 soil treatments. In connection with this diagram, there should be a 

 record book, in which should be entered the dates of all operations and 

 other items bearing upon the progress of the experiment. It is never 

 advisable to trust to memory or to field stakes for the plan of the ex- 

 periment. 



Record of the Experiment. — The following form will be found conven- 

 ient for keeping the final data of a field experiment which is continued 

 from year to year: 



FORM FOR PLOT EXPERIMENT DATA. 



