N". C. Experiment Station 
7 
lata. Frank (7) observed a sclerotial disease of peanuts of whose iden¬ 
tity lie could not be certain since lie did not have the apotkecial stage, 
but lie may have been dealing with the same organism. 
Names of the Disease 
As is the case with many plant diseases, various common names have 
been applied to this disease, although the name stem rot seems to be 
most appropriate. Among other names which have been employed are 
clover rot, wilt, and root rot. In England the name clover sickness has 
long been employed and other European accounts make use of the 
names Sclerotium rot, clover rot (Kleefaule), and clover canker (Klee- 
krebs). 
Description of Clover Stem Rot 
Stem rot on crimson clover can first be noticed in the fall when the 
plants are still small. It continues to spread, however, when weather 
conditions permit, throughout the winter months and is destructive until 
the time when unaffected plants are mature. The first evidence of the 
presence of the disease is manifested by a wilting of the stem and 
leaves. These portions then turn yellowish, rather quickly succumb and 
become brown (Plate 3, Fig. 1). Closer examination discloses the fact 
that the stems near the base of the stool or at the ground level are in¬ 
volved in decay, which begins as a slight discoloration and proceeds 
until the stems have rotted off. At this time a dense, white, mold-like 
growth is prominently present at the base of affected stems. In the 
presence of a suitable supply of moisture this fungous growth becomes 
more profuse and within a few days, compact masses of liyphae will 
have formed on the surface of the decaying stems (Plate 3, Eig. 1). 
These masses soon become black in color and of a cartilaginous con¬ 
sistency and are the sclerotial stage of the causal organism. 
These black sclerotia are sometimes as large as a pea and their pres¬ 
ence can be used as an aid in a field diagnosis of the disease. With the 
maturing of these sclerotia and the simultaneous disintegration of the 
stems, the sclerotia remain scattered over the soil where the plant has 
been. Meanwhile, the roots also are involved in decay and the sclerotia 
which are formed as the tissues become decomposed, remain in the soil 
Since the disease spreads outward from a center of infection, plants in 
all stages of the disease may be found in any one spot. When the dis¬ 
eased areas are large the centers may be entirely bare or there may 
remain the debris of the badly decayed stems. The stand of clover, in 
case plants die in localized areas, is thus rendered not uniform or when 
the centers of infection are numerous and extremely favorable con¬ 
ditions prevail, the stand may be rather uniformly destroyed. 
