2 



FIELD CROPS 



the lower nodes. The conditions that hinder tillering 

 (sometimes limiting the number of stems to one or two to 

 the plant) are thick sowing, late sowing, and deficiency 

 of moisture or plant-food. 



3. Leaves. The leaf-blade of the oat is wider than that 

 of wheat or rye, and on its margins are scattering hairs so 

 fine as to be noticed only on care- 

 ful examination. 



At the junction of the leaf -blade 

 and sheath there are no clasps 

 or auricles (Fig. 1), which absence 

 serves to distinguish the young 

 oat plant from that of any other 

 small grain. 



4. Pollination. The oat in na- 

 ture is self-pollinated ; hence there 

 is practically no danger of crossing 

 between different varieties. Sev- 

 eral varieties may properly be 

 sown in adjacent fields, if care 

 is taken to prevent mixing by me- 

 chanical means, as in harvesting 

 and threshing. 



5. The panicle and spikelets. 

 The grain-bearing part of the 

 plant, though usually called a 



head, is really a panicle, or widely branched terminal part 

 of the stem (Fig. 2). The branches of the head originate 

 at the upper nodes or joints of the stem, several usually 

 springing from each node. Each branch may bear a single 

 spikelet (that is, a group of grains) or several spikelets. 



FIG. 1. PART OF AN OAT 

 PLANT. 



Showing the absence of 

 clasps where leaf-blade and 

 sheath join. 



