106 FIELD CROP PRODUCTION 



less, awnless, or bald varieties. The palea is a thin, mem- 

 braneous glume, the edges of which are folded inside of 

 the flowering glume. The flower proper is inclosed within 

 and consists of the ovulary, stigma, and stamens. The 

 stamens are three in number, the filament of which is 

 short before fertilization, bearing at the top an elongated 

 anther. The stigma is composed of two branches, each 

 provided with tiny, feathery branches to catch the pollen. 

 Wheat is a close or self-pollinated plant. When the time 

 comes for fertilization, the filaments of the stamens rapidly 

 elongate, and in so doing, upset the anthers, which spill 

 the pollen on the stigmas. While the spikelet may have 

 from 2 to 5 flowers, usually only 2 or 3 develop. Those 

 which do not develop are called sterile flowers. When 

 seeded thickly or on poor soil, or if not favored with good 

 growing weather, fewer flowers develop. Usually 2 or 3 

 flowers of each spikelet develop, however, and under 

 favorable conditions as many as 5 may mature grains. 

 The number of kernels per spike, therefore, varies greatly 

 in the same field, or even in different spikes of the same 

 plant. In the threshing of wheat, the kernel is liberated 

 from the outer and flowering glumes and from the palea, 

 all of which taken together are called the chaff. 



89. The kernel. — After fertilization the ovulary devel- 

 ops into an oblong grain, with a deep groove or furrow 

 on the side next to the palea. Great variation in size, 

 shape, color, and hardness is found in the kernels of differ- 

 ent varieties. Slight, or in some cases marked, variations 

 are found among the kernels of a single spike. Upon 

 examination of the kernel, a lot of short hairs will be found 

 at the tip. This is called the brush. If a cross-section 

 be made, it will be seen that the kernel is made up of several 

 distinct parts. The outside covering of the kernel is 



