10 BULLETIN 270, U. S. DEPARTMENT OF AGRICULTURE. 



PLAT RECORDS. 



The first note taken after emergence was of the comparative stand. 

 Since seeding was uniform for each cereal or comparable group of 

 varieties, uniform stands of plants could be expected when the germi- 

 nation was perfect. However, these conditions were noted after the 

 plants emerged and a comparison of stands of the different plats was 

 taken. 



Other important notes were recorded throughout the season, such as 

 dates of heading, ripening, and cutting. If smut, rust, or other dis- 

 eases were present, such data were recorded. 



As each variety was thrashed the weight of the grain from the plat 

 was recorded. This weight was then divided by the standard bushel 

 weight and the yield in bushels per acre determined. 



Previous to 1912 the varieties of cereals were grown in single plats 

 without checks. In 1912 and 1913 check plats were used. In 1914 

 all varieties of cereals were sown in duplicate fiftieth-acre plats. 



SOURCE OF THE SEED. 



The cereals grown in the plat tests have come from many different 

 sources. The first year nearly all of the seed was obtained from the 

 North Dakota Agricultural Experiment Station or from the Edgeley 

 substation. Since that time varieties have been obtained from 

 various sources in North Dakota and in other States, and also from 

 foreign countries having a climate similar to that of the northern 

 Great Plains area. Promising varieties from the cereal nursery also 

 have been increased and grown in the field tests. 



NURSERY EXPERIMENTS. 



Many varieties and races of cereals have been tested in nursery 

 rows. This method has permitted work with a much larger number 

 of varieties here than in the larger plats. The ground used each year 

 was usually cultivated land that had borne potatoes or corn the pre- 

 vious year. In this way the land was kept free from volunteer grain. 

 Special care was given to the selection of uniform soil, to uniformity 

 in the rate of seeding, and to the spacing and length of rows. More 

 detailed notes were made throughout the season than were taken of 

 the varietal plats under field conditions. 



The nursery consisted of centgeners, head rows, and rod rows. In 

 1908 it was planted entirely in centgeners, from each of which the best 

 plant was selected each year for planting the following year. The 

 number of centgeners decreased each year until 1912, after which this 

 method was discarded. In 1909 the use of head rows and rod rows 

 was begun, and in 1913 these entirely replaced the centgeners. 



