A Study of Colorado Wheat 
9 
velopment, so that no difference in the plants grown on these plots 
could be perceived. 
While there were but few, or almost no recognizable differen¬ 
ces in the growth and ripening of the plants in comparison with the 
check plots, there were differences in the physical properties of the 
kernels. The kernels grown with the application of phosphorus, of 
potassium, and those on the check plots, were plump and of good size, 
while those grown with the application of nitrate, were smaller and 
somewhat shrunken. The chief physicak characteristics were shown 
by the wheats grown with the addition of potassium and these 
were most pronounced in the Kubanka. These wheats show a dif¬ 
ference in their general appearance, in the brightness of the kernel, 
and especially in the presence of mealy or half-mealy kernels. Yel¬ 
low-berry was more prevalent than in wheats from the other plots, 
i.e., than in either those from the check' plots or such as had been 
grown with the application of phosphorus. There are no decided dif¬ 
ferences between the physical appearances of wheats grown on check 
plots and those grown with the application of phosphorus. This is not 
the case with wheat grown with the addition of nitrogen; such wheats 
are, as has already been stated, small grained or even shrunken, dark 
colored, and flinty. The starchy or mealy berries are either greatly 
lessened in number or are absent. 
Sp far, we have stated the physical differences shown by the 
plants and also the kernels. Bulletin 205 deals with the physical prop’ 
erties of the kernels, while Bulletins 208 and 217 deal with the soil, 
the chemical composition of the plants, and some other factors. There 
we find that these fertilizers exert specific influences which are not 
apparent in the physical appearance of the plants. The greatest cor¬ 
respondence between the physical appearance and chemical effects is 
found in the case of nitrogen, which produces in the plant an appear¬ 
ance of luxuriance. We find that it increases the nitrogen content of 
the plant, and modifies the amount and percentage composition of the 
ash. Further, these elements, nitrogen, phosphorus, and potassium, 
mutually influence the intake of one another; for instance, nitrogen, 
applied in liberal quantities, increases the amount of potassium appro¬ 
priated by the plant. As I have applied only sodic nitrate as a source 
of nitrogen, it is possible that this effect may be attributed to the action 
of the sodium upon the soil. Be this as it may, the amount of potas¬ 
sium appropriated was increased, also the amounts of lime and mag¬ 
nesium, while the amount of phosphorus appropriated by the plant or 
found in its ash was not influenced. The succulency of the plant wa- 
increased, or, put the other way, the amount of dry matter in the plant 
was decreased. Phosphorus did not appear to exercise any marked 
influence upon the nitrogen content of the plant; potassium lowered it. 
Bulletins 208 and 217 treat of these features more fully. 
