270 IOWA DEPARTMENT OF AGRICULTURE. 



but half of the protein, this most important food consiiment, is in the ea'* 

 and where the stalks and leaves are wasted, half of the protein is wasted, 

 another argument for the silo, Mr. Trow has handled the silo topic so well 

 that I shall not attempt to add anything to his statement farther than can 

 be drawn as necessary inference from what I must say. The fact that half 

 the protein is in the stalks and leaves shows the wisdom of using the method, 

 the sole method which saves leaves and stalks in form to be eaten by the cows. 

 Note farther, that cne-third of the total protein of the plant is in the leaves. 

 They must be fed. In all the earlier stages of the growth of the plant pre- 

 ceding maturity, the bulk of the protein is in the leaves, and it is not until 

 the ripening process is well under way that it is transferred to the ears. On 

 seventh of September, for instance, in a certain year, 40 per cent of the pro- 

 tein was still in the leaves Note, too, that the stalk contains but 17 per 

 cent of the total protein of the plant. Remember, too, that this protein is 

 digested with difficulty by the cow, because, especially in the lower part of 

 the stalk where it is coarse and woody, it is encased in fibrous material. 

 Experiments have shown that often it takes as much energy to digest this 

 coarse stuff as it furnishes when digested. It is not certain, therefore, that 

 the saving of the butts of the stalks is really a contribution to the supply of 

 desirable food stufifs. Perhaps we have argued too much from the analyses 

 of the chemist as to the real value of these lower parts of the cornstalks, 

 and it is not yet fully settled that the losses through Iowa are as great as was 

 at one time thought, due to the waste of the coarser parts of the stalks, left 

 in the fields to be plowed under. 



Not far from fifty- five per cent of the starches and sugars of the entire 

 plant are found in the ear, about thirty per cent in the stalk and but fifteen 

 per cent in the leaves where they would be washed out by rains. Note, 

 though, that all these figures do point to the economy of saving leaves and 

 stems to feed with the ear. 



A long series of experiments show that the gross weight of leaves on an 

 acre of corn does not increase after the corn is in the milk; the weight of the 

 stalks remains about constant but the ear does increase in weight rapidly. 



The question when a field of corn contains the greatest amount of valu- 

 able feeding material is an important one. In Michigan after about the 

 25th of August in an average year, when the corn was in the roasting stage, 

 there was no increase in the average weight of a stalk of corn bearing an 

 ear. There was of course and increase in the weight of the ear owing to the 

 migration of material from the stalks to the ear but there was not an increase 

 in the weight of the plant as a whole. On August 10th a certain field of 

 corn was in full tassel. On the 25th it was in the roasting stage, on 

 the 6th of September it was glazing and on the 15th was fully ripe. I am 

 going to insert a table here which I shall not read but which I shall ask to 

 have printed. 



