1180 
Journal of Agricultural Research 
Vol. XXXI, No. 12 
Atkinson, Whitlock, and Jahnke ( 1 ) investigated the seed value of 
frosted wheat. They separated into two parts each of 32 samples of 
wheat which contained a large percentage of frosted kernels, one con¬ 
taining only kernels showing frost injury and the other containing 
kernels showing no frost injury. The germination of these samples 
was tested in the field. The average germination of the frosted sam¬ 
ples was 75 per cent and that of the nonfrosted 78 per cent. Their 
results show a greater number of heads per row and a higher yield 
from the frosted kernels. They state: 
The difference is not great enough to be very significant, yet it shows that ker¬ 
nels showing frost injury are not necessarily worthless for seed. It should be 
understood that grain may be entirely destroyed by frost, so far as its seed value 
is concerned, but this test suggests that all grain need not be discarded for seed 
purposes because it shows frost injury. The only safe plan is to have it tested 
before deciding either to use or discard it. 
Atkinson and Jahnke (2) carried out further investigations on the 
germination of frosted wheat along somewhat the same line. The 
report of their experiments indicates that the frosted wheat showed 
a less germination than the nonfrosted wheat separated from the 
same samples. 
Miss Lute (11) states that frosted wheat from San Luis Valley, 
Colo., showed low germination, but gives no definite data on the sub¬ 
ject. 
The effect of freezing temperatures produced by artificial means on 
the germination of seeds has been studied by a number of investi¬ 
gators. Detmer (4) states that air-dry wheat kernels can be sub¬ 
jected to temperatures of —5° to —10° C. without injuring their 
germination, while if the turgid kernels are subjected to these tem¬ 
peratures the germination is injured. Thiselton-D^er (IS) found 
that air-dry wheat kernels could be subjected to the temperature of 
liquid hydrogen for 1 hour without injuring their germination. Bec- 
querel (8) subjected air-dry wheat kernels to liquid air for 130 hours 
and found that germination was unimpaired after this treatment. 
EXPERIMENTAL DATA 
A part of a 1923 crop of Marquis wheat was purchased from a far¬ 
mer living near the Montana Agricultural Experiment Station. 
This wheat was grown under a system of dry farming. Portions of 
the wheat were harvested at intervals of two to four days during the 
development of the kernel. In order to restrict the amount of ma¬ 
terial flowing into the kernel after harvest, only the heads were 
gathered. Enough heads were obtained at a time to fill six 24- 
pound flour sacks. Three of these sacks were placed in the hardening 
room of an ice-cream manufacturing plant for 48 hours, after which 
time they were spread on the floor of a large room to dry. The other 
three sacks picked at the same time were at once spread on the floor 
to dry. The temperature of the hardening room ranged between 
— 20° and — 28° C. After the heads became dry they were threshed. 
The moisture content of the kernels was determined at the time 
of harvest. The values obtained are given in Table I. The weight 
per kernel was calculated from the weight of 1,000 kernels. Typical 
frozen and nonfrozen kernels at four stages of development were 
photographed (pi. 1). Estimating the age of the kernels from the 
