ALFALFA ROOT STUDIES. 
21 
YELLOW-FLOWERED ALFALFA. 
While several introductions of yellow-flowered alfalfa (Medicago 
falcata) have been made since 1897, none of them is of commercial 
importance. As a whole, they are characterized by many branch 
roots, which taper so gradually that they are often as large at a 
distance of 2 or 3 feet as they are at the point of origin. They 
usually extend to a greater depth than the taproot — where it is pres- 
ent. Fibrous roots are abundant, especially near the surface. Crown 
branches and rhizomes are small and numerous. Based upon man- 
ner of growth, these alfalfas may be divided into three general 
classes: (1) Erect, with narrow crowns, upright stems, and root 
system, like Medicago sativa; (2) prostrate, with broad, deep-set 
crowns, prostrate stems, and a much-branched root system; and (3) 
Fig. 11 
Root systems of plants of yellow-flowered alfalfa (Medicago falcata), the 
growth of two seasons. 
decumbent, intermediate between Nos. 1 and 2 as to root system and 
general habit of growth. At Redfield the roots of the yellow- 
flowered alfalfa seldom reach a depth greater than 5 feet, while 
Grimm alfalfa, grown under similar conditions, attains a depth of 
10 feet. 6 
Erect yellow -flowered alfalfa. 7 — The erect form of Medicago 
falcata is distinguished from the other types of the species by the 
shape of the crown and the prominence of the taproot, which is rela- 
tively small but quite as distinct as that of the Grimm alfalfa. The 
branch roots are more numerous, smaller, and more slowly tapering. 
6 Frank N. Meyer reports roots of large size growing in open sandy soils on the banks 
of the Tom River near Tomsk, Siberia. Some plants were- found with roots fully 2 inches 
in diameter at the crown and more than 1 inch in diameter at a depth of 14 feet. A 
few of the roots were found to extend to a depth of 33 feet. 
7 S. P. I. No. 20721 (Medicago falcata), from Samara Province, Russia, as found wild. 
(See S. P. I. No. 20726.) 
