268 



ing can be made the basis of a very close estimate of the date of 

 i-ipening. 



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 Aveight. 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 

 internal 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 liecause 

 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 

 j:)assage 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 Avheat is an accident that one dreads 

 most at this period. The blight, 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 

 moisture in the soil or a less active transpiration would have given a 

 better result. But we often confound the blight, 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 shoidd 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. 



