14 
BULLETIN 1087, U. S. DEPARTMENT OP AGRICULTURE. 
POONA ALFALFA. 
In 1913 the United States Department of Agriculture received 
seed of a distinct variety of Medicago sativa from west-central India. 
This alfalfa, which has been given the name of Poona, from its 
source, has proved to be even less hardy than the Peruvian variety. 
Poona alfalfa, seeded at Redfield in 1915 suffered complete mortality 
the following winter, while Peruvian seeded under the same condi- 
tions had a small percentage of survival. The variety is charac- 
terized by narrow, upright crowns, few crown branches, and very 
few, if any, rooting rhizomes. It differs from most other varieties 
in the almost entire absence of branch roots on the upper portion of 
the taproot. At a depth of 8 to 12 inches, however, branch roots are 
Fig. 9. — Root systems of decumbent plants of yellow-flowered alfalfa (Medicago falcata). 
No winterkilling and very little injury occurred in this alfalfa during the 6-year 
period from 1915 to 1920, inclusive. 
relatively profuse. Fibrous roots are sparse and rather uniformly 
distributed over the root system. The differences between roots of 
one season's growth of this and other varieties and strains are shown 
by a comparison of Figure 11 with Figures 10 and 12 to 11, inclusive. 
COMMON ALFALFAS. 
The common alfalfas include the purple-flowered strains generally 
grown throughout the western United States. It is believed that 
practically all of them have a common lineage, being descended from 
stock introduced into California during the early history of that 
State. For convenience they may be arbitrarily placed in two 
groups: Southern-grown common and northern-grown common. 
SOUTHERN-GROWN COMMON ALFALFA. 
Having comparatively small, upright crowns and pronounced tap- 
roots, southern-grown common alfalfa also has relatively few branch 
