Freezing Injury of Seed Corn 57 
The corn was grouped according to its moisture content, 
with a range of 5 per cent for each group. Corn ranging 
in moisture content from 10 to 15 per cent, and 15 to 20 per 
cent gave 100 per cent germination; 20 to 25 per cent moisture 
germinated 93 per cent ; 25 to 30 per cent moisture germinated 
43 per cent; 30 to 35 per cent moisture germinated 24 per cent; 
and 35 to 40 per cent moisture germinated 3 per cent. 
These results conform very closely to those from the lab- 
oratory tests at a temperature range of 16° to 12° F.. as may be 
seen by comparing with Table 7. In the laboratory, when 
subjected to a temperature of 16° to 12° F., corn containing 
15 to 20, 20 to 25, 25 to 30, 30 to 35, and 35 to 40 per cent of 
water germinated respectively 100, 88, 34, 12, and 0 per cent, 
while the same grades of corn exposed in the field to a mini- 
mum temperature of 15° F. germinated respectively 100, 93, 
43, 24, and 3 jeer cent. 
FIELD SELECTION IN 1914 
The results for corn selected from the field on November 22, 
1914, after intermittent subjection to 111 hours freezing tem- 
perature with a minimum of 4° F. are given in Table 19. 
The freezing temperatures ere given in detail in Table 20 and 
are summarized in Table 21, which gives the duration and the 
mean, and minimum temperatures for each freezing period. 
The respective mean germinations were 100, 67.5, 60, 55, and 
30 per cent according to whether the moisture content of the 
grain ranged from 10 to 15, 15 to 20, 20 to 25, 25 to 30, or 
30 to 35 jier cent. 
FIELD SELECTION IN 1915 
A study was made in the fall of 1915 of the effect of early 
freezing temperatures on the vitality of corn when left in the 
field and exposed to the natural freezing weather of October 
and November. This year the corn was very immature at the 
time of the first killing frost and continued to retain a large 
per cent of water thruout the fall. Since there was also 
considerable variation in the maturity of individual ears, the 
opportunity was exceptionally good for studies of this kind. 
The freezing temperatures which occurred during the fall are 
recorded in Table 24, and put in summary form in Table 25. 
It will be noted from these that the first freezing occurred on 
October 8, and again on October 9. The first was very light 
and of short duration, while the second was more severe and 
slightly longer. 
