128 THE SOILS- AND CROPS OF THE FARM. 



get nearly, if not entirely, ripe, but if it is necessary to 

 cut at a much greener stage, shocking and capping 

 would probably be beneficial. Of course there is al- 

 ways danger from over-ripe grain shelling out in har- 

 vesting, also danger from lodging. 



It has been found that, in general, there is a de- 

 crease in percentage of albuminoids, fibre and ash as 

 the wheat becomes ripe. This is doubtless due to the 

 starch or endosperm developing later in the growth of 

 the wheat. The germ develops first, and later, when 

 the endosperm develops, the percentage of albuminoids 

 becomes less, although the actual amount may remain 

 the same, or, as is probably the case, may increase. 

 The higher per cent, of albuminoids in the spring 

 wheats may be due to a less full development. 



Plant Diseases. — Wheat is subject to three com- 

 mon diseases: rust, stinking smut or bunt and black 

 smut. 



Bust is caused by, or rather is, the general term for 

 several species of fungi, the best known of which is 

 called by botanists Puccinia graminis. The life his- 

 tory of this fungus is supposed to be about as follows: 

 Certain forms of the plant grow in the leaves of the 

 barbary plants and perhaps other plants. On the 

 leaves of the barbary plant there appears in the spring 

 certain orange- colored spots. These spots are com- 

 posed of many spores which, getting upon the leaves 

 of the wheat, in some way not well understood, enter 

 through the breathing pores. The spores produce 

 microscopic plants which grow within the wheat plant 

 and upon its substance. A wheat plant infected with 

 the rust plant has not only to support itself but also 

 to support the rust plant. This it is more or less un- 



