Relation of Size of Seed and Sprout Value to Yield 23 
and stem growth and inert seed remains determined. The 
results of the three separate tests are given in table 7 together 
with the average for all three tests. The average dry matter in 
the total vegetative growth (stem and root growth) equaled 47.28 
per cent of the original dry matter in the seed. The average 
carbon dioxide liberated equaled 39.22 per cent of the original 
moisture-free seed. The combined weights of the root growth, 
stem growth, CO2, and inert seed residue exceeded the moisture- 
free weight of the seed 2.4 per cent. This slight discrepancy 
may result in part from the manner of determining the moisture- 
free weight of the seed planted. The sample to be germinated 
could not be dried at 110° C. without destroying its viability. 
Consequently, the moisture-free weight of a parallel sample from 
the same composite lot of seed was used. The samples may not 
have been exact duplicates. 
RELATION OF SIZE AND SPROUT VALUE OF SEED TO YIELD AT DIFFERENT 
DEPTHS OF PLANTING 
For the purpose of supplementing the sprout value determina- 
tions (pp. 10-20) with wheat seeds of various grades, several 
distinct grades of fall and spring wheat were grown during 1914 
and 1915 at different depths of planting in the wheat nursery. 
The object of the tests was to determine the relation of size and 
sprout value of wheat seed to its relative ability to germinate, 
grow, and yield as the depth of planting is increased. (The 
customary depth in farm practice is about 2 inches.) 
All plantings were made by hand at the ordinary field rate, in 
duplicate nursery blocks containing 5 rows, 7f feet long and 8 
inches apart. The two outside rows of each block were dis- 
carded at time of harvest to eliminate the effect of competition 
between plats. 
The results for 3 grades of Turkey Red winter wheat planted 
1, 3, and 5 inches deep are recorded in table 8, while table 9 
summarizes the results for two grades each of Scotch Fife and 
Marquis spring wheat. 
In case of the winter wheat, as shown in table 8, small plump 
winter wheat seed appeared to be at no disadvantage when 
planted up to a depth of 5 inches, as compared with large plump 
seed, even tho the sprout value was only 64.3 per cent as 
large. However, the small shrivelled seed, having only 38.6 per 
cent as much sprout value as the large plump seed, was at a 
marked disadvantage when planted either 3 or 5 inches deep. 
As an average for the two varieties of spring wheat, small 
seed (having a relatively lower sprout value of 29.7 per cent than 
the large seed) was at a relatively greater disadvantage than the 
