268 
ing can be made the basis of a very cfose estimate of the date of 
ripening. 
The date of flowering occurs at the time of the greatest vital 
activity of the plant, which at that time is actively drawing its 
nourishment from the soil and is transpiring, assimilating, and 
increasing in weight. But very soon this work is relaxed and is 
confined more and more to the interior of the plant, conveying into 
the seed the elaborated materials formed within the leaves and stems. 
It is especially in this latter part of the life of the plant that the 
mternal consumption can exceed the gain from without, and the 
plant tends to diminish its dry weight. 
This period has a great influence on the final result, not only because 
the plant can gain as a whole, but especially because of the distribu- 
tion which is made within it of the material which it has brought 
together. The straw has only a secondary value. It is the seed 
which constitutes nearly the whole value of the harvest. Therefore 
all that passes from the straw to the grain is a benefit, though this 
passage should be accompanied by a notable consumption of the 
nutritious materials of the stalk. It is neither the state of prepara- 
tion of the stalk, nor the heat, nor the radiation, nor the moisture 
which of itself alone produces the best quality of grain. There must 
be a reunion of all these various elements in a proper proportion, which 
latter will vary with the weather and with the locality even with the 
same weather. The blighting of wheat is an accident that one dreads 
most at this period. The bhght, properly so called, is due to a tem- 
perature and a radiation that is too intense for the movement of the 
sap in the plant; the seed has not time to receive the sum total of the 
nourishing particles that have been prepared for it; therefore it 
becomes small, lean, and shriveled up. <A greater sum total of 
inoisture in the soil or a less active transpiration would have given a 
better result. But we often confound the bight, properly so called, 
with the analogous result produced by an insufficient assimilation or 
elaboration of the various materials that go to make up the wheat 
grain or by a disproportion in the relative quantities of the elements 
that should make up the seed. 
The following table shows the number of days elapsing from sow- 
ing to ripening for the dates adopted in the previous tables. It is 
calculated by first ascertaining the number of days elapsing from 
flowering to ripening according to the rule above given and then 
adding these intervals to those already calculated for the flowering. 
