14 BULLETIN 981, TJ. S. BEPAETMEISTT OP AGRICULTURE. 



by the Office of Forage-Crop Investigations were found in September, 

 1912, in a field of Sumac sorgo on the farm of Mrs. Flynn, near Chilli- 

 cothe, Tex. This field was badly infested with Johnson grass, and a 

 number of plants were discovered which showed evidences of hybrid 

 origin. Seed was gathered from these plants, and two of them were 

 dug up and transplanted at the field station. One of these plants 

 had elementary rootstocks, and the other, though it lacked any well- 

 developed rootstocks, had a panicle that clearly showed a relationship 

 with Johnson grass. 



Fig. 10. — Root of a hybrid between Sumac sorgo and Johnson grass, F. C I. No. 5848, showing the devel- 

 opment of rhizomes. 



Neither of the plants which had been reset at the field station lived 

 over winter, but the seed from these and other hybrid plants was sown 

 at the Chillicothe Field Station and at the Arlington Experimental 

 Farm, Va., in the spring of 1913. In the resulting crop there were 

 at least four distinct forms. Some had well-developed rootstocks 

 (fig. 10) , while others, even though they resembled Johnson grass more 

 closely in stem and leaf characters, had no rootstocks at all. There 

 was also a wide variation in the juiciness and sweetness of the stems, 

 one form being quite as juicy and sweet as Sumac sorgo, while other 

 forms had pithy stems. 



