EXERCISE 16 (Continued) 



Directions. Describe the types according to the outline on the pre- 

 ceding page. For descriptive terms see Productive Farm Crops, end of 

 Chapter XXIII. 



II. Lay out spikes of six-row, common six-row and two-row barleys. 

 Lay a brace of spikelets from each type just below the respective types. Draw 

 each brace (enlarged X 3), showing (1) relative size of the three spikelets 

 in a brace in the six-row types, (2) straightness of the grains, (3) length of the 

 grains, (4) prominence of the two nerves on the back of the spikelet. After 

 making these drawings answer the following questions: 



1. How may we distinguish erect six-row (hexastichum) barley in the 

 threshed sample? 



2. How may we distinguish the common nodding six-row (vulgare) in 

 the threshed sample? 



3. How may we distinguish two-row barley (distichum) in the threshed 

 sample? 



4. How may we distinguish two-row barley (zeocrithum) in the threshed 

 sample. 



Reference. Harlan, H. V.: United States Department of Agriculture, 

 Bulletin 622. Montgomery, E. G., 1916, Productive Farm Crops (LIPPIN- 

 COTT), Chap. XXIII. Carleton, M. A., 1916, The Small Grains (Macmillan) . 



LABELS 



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