28 The Colorado Experiment Station 
ii.i tons, again 14.1 percent sugar, 11.5 tons. In another district 
a very badly affected held yielded 14.2 tons per acre with 14.6 per¬ 
cent sugar in the beets and a slightly affected held yielded 11.2 tons 
with 15.2 percent sugar in the beets. The 127 helds selected from 
different districts and showing the effects of the leaf-spot in varying 
degrees show a tonnage and sugar content quite up to the average. 
The higher percentages in some of the samples cannot be attributed 
to the drying out of the beets in the ground for the ground was as 
moist as in other helds and the beets continued to produce new 
leaves, in other words, to grow. Neither the percentage of sugar 
in the beets nor the yield of beets in the various districts show such 
persistent and concordant relations to the virulence of the attack as 
to make evident beyond doubt the kind and extent of the injury to 
be attributed to this disease. 
I have said that it is not permissible to compare the results ob¬ 
tained in one district with those obtained from another, much less 
is it permissible to compare results obtained in one section of the 
state with those obtained in another; for instance, the Department 
of Agronomy at the College had two small fields planted to sugar 
beets in 1910. There was some leaf-spot on them. The fields were 
planted early, the varieties were good ones, the seed'reliable, the 
cultivation and stand were also good and the soil most excellent in 
quality; there was no reason why either the yield of beets or the 
percentage of sugar should be low, but the yield was seven tons per 
acre and the best percentage of sugar obtained from any sample 
taken was 13.3 with a coefficient of purity of 79-6- The leaves on 
these beets were exceedingly heavy and remained green till actually 
frozen, about Nov. 7. No one who saw this field would for a 
moment think of attributing the disappointingly low yield, the low 
percentage of sugar and low coefficient of purity to the damage done 
by the leaf-spot, for while leaf-spot was present the foliage was not 
damaged in any noticeable degree. It would be wholly wrong to 
attempt to compare such a field as this with the fields in the Arkansas 
Valley. 
There is no question but that water will drown plants and that 
alkali may be so excessive and of such composition as to kill them. 
The question, to be answered is whether they have done as much . 
damage as we think them to have done or are we attributing bad 
effects to these causes which are due to others ? I think that we are 
doing the latter to a very considerable extent. There is no question 
but that to fertilize the soil is a good and proper thing to do. The 
question is how much relief have we to expect from this ? We have 
given the best answer that we can so far as the yield of beets and 
the percentage of sugar is affected by the usual fertilizers used for 
this purpose, i. e., nitrates, ammonia salts, dried blood, superphos- 
