TREATMENTS OF SEED WHEAT FOR LOOSE SMTJT 15 
by the single-bath method. On the other hand, when the seed coats 
were broken the percentage of germination of seeds treated by the 
modified hot-water method ran from 10 to 29 per cent lower than 
that of seeds treated by the single-bath method, depending upon the 
location of the break in the seed coat. 
It has been noted that germination was markedly reduced as a result 
of hot-water treatment when the seed coats were broken and that 
very lit.le or no reduction in germination was brought about when the 
seed coats were intact. It was noted also that the seed coats are 
more susceptible to breakage in threshing in dry years and less sus- 
ceptible in wet years. It is evident, therefore, that the effects of 
hot-water treatments on germination are ultimately dependent to a 
considerable extent on the weather conditions which prevail during 
the ripening, harvesting, and threshing of the grain, and that we may 
expect variable responses to treatment from year to year. On this 
point the observations of Baudys (2) are interesting. He notes that 
a variety may differ in susceptibility to hot-water injury from year 
to year and therefore requires annual determinations of the proper 
temperatures for the treatment bath. 
YIELD 
In studies previously reported by the writer (15) some evidence was 
obtained indicating that the injurious effects of the modified hot- 
water treatment may extend into the later stages of plant growth. 
The results presented in Table 6 plainly show that the plants from 
treated seed suffered a lessened capacity to withstand unfavorable 
soil conditions. In the absence of data on the germination of un- 
treated and treated seed, however, it is impossible to state whether 
this difference was due to a decreased emergence of seedlings from 
the treated wheat or to a lessened post-germination capacity on the 
part of the plants which developed from treated wheat. 
In a yield test conducted in 1923-24 an attempt was made to 
study further the post-germination effects of hot-water treatments. 
To this end unsmutted seed was used, and in some of the plats the 
rate of seeding of the treated wheat was increased to compensate 
for the reduction in germination resulting from treatment. Any 
differences which might have affected the yields of the plants from 
untreated and treated seed were therefore eliminated, except the 
differences brought about by treatment. On September 22 definite 
quantities of each of two lots of wheat grown on Arlington Experi- 
ment Farm in 1923 were weighed and measured, treated as shown in 
Table 9, spread in thin layers, and left to dry. On October 2, 200 
untreated seeds and 200 seeds from each of the treatments of each 
lot were sown at Arlington Experiment Farm on the land which later 
was used for the yield test. At this time the treated seed had 
regained its original weight and volume. Germination counts were 
taken after three weeks. On October 27 the untreated and treated 
seed of both lots were sown in fortieth-acre plats. In half of the plats 
sown with treated seed the rate of sowing was increased to compensate 
for reduction in germination. The drill which was used could not 
be adjusted to differences in rates less than one-half peck. There- 
fore the nearer half-peck rate was used when the calculated rate fell 
between half pecks. Tests made previous to sowing showed that 
the drill delivered the seed at rates which closely approximated the 
rates at which it was set. 
