60 BULLETIN 618, U. S. DEPARTMENT OF AGRICULTURE. 
(2) No spring wheats do well in the southern part of the Great 
Plains. 
(3) Wherever the hard red winter wheats of the Crimean group 
can be grown commercially they are better yielders than any spring 
wheat. In the higher and drier parts of the plains of Colorado and 
Wyoming and in central South Dakota their advantage is very 
small. 
(4) In the central and northern parts of this area, wherever 
spring wheat is commercially important, durum exceeds spring 
common wheat in yield almost without exception. Usually this 
is by a large margin, of 10 to 30 per cent, but occasionally by as little 
as 5 per cent. 
(5) Of all the varieties of durum wheat tested in this area, the 
Kubanka is best adapted to all the varying conditions. It is most 
suitable for central and western North and South Dakota and 
eastern Montana, at altitudes ranging from 1,800 to 4,000 feet. 
The Arnautka is slightly better adapted to the more humid eastern 
part of the Northern Plains with altitudes ranging from 1,000 to 
1,800 feet. The Pelissier is a better yielder in the western and drier 
sections at altitudes of 4,000 to 6,000 feet. 
(6) A number of pure-line selections of durum wheat are proving 
better adapted to the local conditions where they were developed 
than are the older standard varieties. Three which differ appre- 
ciably from the standard varieties from which they were selected 
have been named. Five of these races appear to be of sufficient 
value to be tested under a wide range of conditions. They are as 
follows: Acme (C. I. No. 5284), a selection from Kubanka (C. I. No. 
1516) made at Highmore, S. Dak.; Arnautka (C. I. No. 4064) a selec- 
tion from Arnautka (C. I. No. 1494) made at Akron, Colo.; Monad 
(C. I. No. 3320), a selection made from a field in Russia but tested 
at Dickinson, N. Dak.; Buford (C. I. No. 5295), a selection from 
Taganrog (C. I. No. 1570) made at Willis ton, N. Dak.; Kubanka No. 
8 (C. I. No. 4063), a selection from Kubanka (C. I. No. 1440) made 
at Dickinson, N. Dak. Of these five, Acme and Monad are very 
rust resistant. 
THE ARID BASIN AND COASTAL AREAS. 
A study of the data from the six stations located in these western 
areas, as summarized in Table XXXIII, shows two facts definitely. 
(1) Except for the Crimean group of winter wheats, the standard 
varieties of the western areas differ from those of the Great Plains 
and Prairie States. 
(2) In these areas the better yields have been obtained from 
hard red winter wheats of the Crimean group or from some variety 
of soft white wheat. 
