s 
Colorado Expkriment Station 
amounts of ash-constituents. The variety of wheat referred to was 
th^! same and grown on the same land with the same fertilization. 
Further, it is a matter of common knowledge that a very light rainfall 
or heavy fog, just before the ripening period, may cause injury both 
to the quantity and quality of the crop. If this were not already so 
well known, we would appeal to our experience in 1914, when a com¬ 
paratively small amount of rainfall injured our Defiance plots to an 
extreme extent and all of the plots seriously. In this case rust pro¬ 
duced severe injury to the crop, but especially to the Defiance. There 
were some effects which could not be attributed directly to this para¬ 
site, especially in the light of other experiences, but probably should 
be attributed directly to the wetting of the plants. 
EFFECTS OF NITROGEN, PHOSPHORUS AND POTASSIUM 
To return to our subject, we found that under our conditions 
nitrogen produces the most marked effects upon the growth and com¬ 
position of the plants; that phosphorus and potassium produced less 
effect than other observers have recorded. For instance, phosphorus 
did not hasten, nor the nitrate delay, maturation as observed by others. 
This statement holds irrespective of the amounts applied. It is true 
that rust interfered two years out of three, particularly in the case of 
the Defiance. . 
In the case of the Defiance, all amounts of nitrates applied caused 
lodging, and that badly. It produced the same tendency in the Red 
Fife and Kubanka, but these varieties did not suffer much on this 
account; they did, however, show other effects of the nitrates, such as 
heavier, darker leaves, slightly taller plants and longer heads, but the 
average number of kernels to the spikelet was found to be slightly 
lower. The kernels were smaller, darker in color, flinty, and some¬ 
times skmuken. 
Phospho'*us, on our plots, produced no perceptible effect upon the 
growth of the plant, the time of ripening, or the physical properties 
of the kernels. 
The plants on the plots which had received dressings of nitrate 
and were planted to Red Fife or Kubanka differed so little from the 
others, that it was only by the darker green color of the plants that 
one could readily distinguish them. This was not the case with the 
Defiance, for in these plots the wheat which had been dressed with 
nitrate went down flat, showing sharply the last drill row to which the 
nitrate wa^ applied. 
Potassium showed at one period a slight hastening in the devel¬ 
opment of the plant, but this advantage was soon lost and plants grown 
on the check plots and on those that had received an application of 
phosphorus, attained the same height and the same perfection of de- 
