470 



Journal of Agricultural Research 



Vol. XIX, No. 9 



kernels from awned spikelets nearer to the base of the spike than is the 

 case in the clipped spikelets. 



DISCUSSION OF RESULTS 



The results in both Minnesota and Idaho have a direct bearing on 

 the two chief field problems in the production of hooded and awnless 

 barleys. These barleys have not yielded as well as the bearded sorts, 

 and they have shattered. 



The barleys from which the awns were removed did not give as high 

 yield in these experiments as the awned plants growing beside them. 

 This conforms to the experience of Zoebl and Mikosch, Schmid, Perlitus, 



/^/77. 



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C/r?. 



2S 



/^a-^sssye a /o// /^/s/^/s/s/7/3/9JX?^/^^^s£|^^s2lS' 

 A/p o/^ A/aa^ /^/?o/^ ^y^S£- o^ ^s^^/A^r 



Fig. 13.— Graph showing relation of length of awn to weight of clipped kernels and undipped spikelets 

 on a 2-rowed barley grown at Arlington Farm, Va. 



and some other investigators. In this study it was evident that the 

 reduction in yield was not due to any injury to the plant, as the differ- 

 ence in growth was not apparent for several days after the awns had 

 been removed. The early growth of the kernels in clipped and normal 

 spikes was equally vigorous. It was only when starch infiltration be- 

 came rapid that the awned spikes showed greater activity. The dififer- 

 ence in ultimate weight was largely due to the difference in the quantity 

 of starch present. There was little difference in the quantities of ash 

 and nitrogen. Zoebl and Mikosch looked upon the awn as an organ of 

 transpiration. Whether the reduction of transpiration alone is suffi- 

 cient to account for the lower rate of starch production is a question. 

 That transpiration has an influence on the behavior of the hooded 



