SUDAN GRASS AND RELATED PLANTS. 7 
known to exist between Sudan grass and the cultivated varieties of 
sorghum. Others, no doubt, will be found in Africa when that conti- 
nent is more carefully explored. No one can foretell the possibilities 
of improvement through the careful hybridization of these new forms 
with our cultivated sorghums. 
TUNIS GRASS. 
There have been at least two distinct importations of Tunis grass 
(Andropogon sorghum virgatus (Hack.) Piper) through the Office of 
Foreign Seed and Plant Introduction of the Bureau of Plant Industry. 
The first, S. P. I. No. 26301, was received from Dr. L. Trabut, Algiers, 
Algeria, December 2, 1909. Ina letter received at a subsequent date 
from Doctor Trabut he says regarding Tunis grass: ‘This grass has 
been accidentally introduced at the botanic station with seeds from 
Egypt, berseem, sorghum, cereals, etc. It has meanwhile become 
naturalized here.’’ The second importation, S. P. I. No. 38108, was 
received May 4, 1914, from Alfred Bircher, of the Middle-Egypt 
Botanic Sasi, Matania el, Saff, Egypt, who. described it as “a 
fodder grass growing spontaneously in Egypt.” 
Evidently Tunis grass, like. Sudan. grass, has been introduced. into 
Egypt and no doubt is found. growing spontaneously where it has 
escaped from cultivation. : It is native, however, in Anglo-Egyptian 
Sudan, where it is found ; growing wild. The Kew and Berlin herbaria 
contain specimens of Tunis: grass from Kordofan, Khartum, El 
Egeda, between Old Dongola and Merowat, between Khartum and 
Berber, and at Matama in northern | Abyssinia, Hackel cites a 
specimen from Senegal also. 
Tunis grass has never been tested so extensively as Sudan grass, 
because it has always appeared less desirable. It is not as leafy as 
Sudan grass (fig. 5), and its seeds shatter so easily that a great deal 
of care is required to obtain a sufficient quantity for field plantings. 
Sear tissue forms at the base of the seed, and it breaks from the 
rachis branch clean, hke Johnson grass. Much of the seed falls from 
the top of the panicle before that at the bottom is ripe and while 
the leaves and stem of the plant are yet green. 
At the Fort Hays Experiment Station, Hays, Kans., in 1914 and 
1915 Tunis grass made an average yield of 8,360 pounds and Sudan 
grass 8,840 pounds of cured hay to the acre. The difference in yield 
is not very large, but the quality of the Tunis grass hay was so in- 
ferior to that of the Sudan grass hay that further tests were not con- 
sidered necessary. R. EK. Karper, superintendent of substation No. 
8, Lubbock, Tex., says in Bulletin No. 219 of the Texas Agricultural 
Experiment Station: “Comparisons of Sudan grass and Tunis 
grass for forage in 1914 resulted in Sudan grass outyielding the latter 
in every case, showing a total average increase of yield of 0.85 ton 
