Deterioration Sugar Beets Due to Nitrates 27 
anything they point to a relation between the yield and the percent¬ 
age of sugar rather than to one between the virulence of the attack 
and this percentage. I do not know the actual average percentage 
of sugar in the crop of 1910 for the whole valley but it was about 
14.0 percent and not above 14.2 percent. It is true that the leaf-spot 
was very prevalent in the valley during this year, and may have in¬ 
fluenced the general average, but the results shown by this compila¬ 
tion of returns from 120 fields representing nearly 2,500 acres, at¬ 
tacked with varying degrees of virulence, leads one to question very 
seriously whether we have not attributed a more injurious effect to 
this fungus than the facts justify. We have no other way that I see 
of judging of these effects than the one here adopted, namely, of 
taking a large number of fields in the same section of country, noting 
the virulence of the attack and comparing the yields and average 
percentages of sugar obtained by taking a sample from each load of 
beets as it is delivered at the factory or dump. We admit that there 
may be errors in the determinations but when we take the average 
of from two loads to four hundred or more loads our approxima¬ 
tion to the truth is very close, besides we are not dealing with differ¬ 
ences of a tenth or two of one percent, but as a glance at the table 
will show, with maximum differences of several percent. A cursory 
examination of the tabulated results makes it evident that we cannot 
compare the samples of one district with those of another. We 
have, for instance, in District No. I, very badly affected fields of 
from six to twelve acres in area, giving averages ranging from 14.7 
to 16.5 percent sugar and yields between 12 and 18 tons per acre, 
while in District No. XVI we have slightly affected fields of 15 to 
20 acres in area, giving averages ranging from 12.5 to 15.2 percent 
of sugar in the beets and yields of from 8 to 10 tons per acre. In 
District No. II in which the fields are mostly about 20, but one was 
much larger, we have eight fields, the lowest average is 13.5 and the 
highest 15.75 with yields of from 7 to 12 tons. These fields were 
all very badly affected. In District No. VI we have likewise eight 
fields either badly or very badly affected. These fields vary from 
12 to 65 acres in area, fl he lowest average percentage of sugar in 
these beets was 11.8, the highest 13*0, the yields ranged from 7 to 
16.5 tons per acre. The irregularity of the results in a given district 
is altogether disconcerting. We can select from these a series of 
results which can be so arranged as to make it appear that the action 
of the leaf-spot is to lower the percentage of sugar and to lessen the 
tonnage of beets, which we would expect to be the case, but this 
would be a case of finding facts to prove a theory. The fact is 
we find in the same district cases of very badly affected fields yield¬ 
ing excellent beets, 15.9 percent sugar, and 11.4 tons and other fields 
only slightly affected yielding beets with 14.7 percent sugar and 
