CABBAGE DISEASES 
ease. It must be dealt with intelligently 
from the first, for, once established, the 
disease is a difficult one to control. 
Brown or Black Rot 
Bacterium campestre (Pam) Erw. Sm. 
Is a serious disease of these two cruci- 
fers, and attacks others of the family, 
including turnips. It is a_ veritable 
scourge to the cabbage growers of Ohio 
and other states. Smith (Farmers’ Bul. 
68, U. S. D. A.) has published concerning 
it and has attributed the disease to a 
specific germ. The diseased heads may 
be dwarfed, in portions rotted, and brown 
colors will appear in the woody layers of 
the plant, including the stem. Badly dis- 
eased heads emit a penetrating and offens- 
ive odor. The losses from the brown rot 
have been very large and specific reme- 
dies cannot be stated. The author quoted 
sums up the subject of treatment in one 
word—prevention. The measures recom- 
mended are—plant on new land and only 
from healthy seed beds; avoid succession 
of the same crops; avoid stable manure 
and give preference to artificial fertilizers 
to escape possible infection through the 
manure. Prevent animals from cropping 
in diseased fields. Clean tools by scour- 
ing bright after use in infected soil. Fight 
the cabbage insects, since these inoculate 
healthy plants with the disease. Removal 
of badly affected plants, or newly infected 
leaves, at intervals, and subsequent burn- 
ing or deep pitting of this refuse may 
aid in checking brown rot. Destroy all 
mustard weeds. 
The water pores of the cabbage are 
large, as is evidenced by the great amount 
of water which collects on the outside of 
the leaves under certain conditions, 
which makes the cabbage quite suscept- 
ible to this form of disease. 
A. D. SELBY, 
Wooster, Ohio. 
Club Root 
Plasmodiophora brassicae 
F. D. BAILEY 
This is a destructive root disease of 
crucifers attacking, among the cultivated 
crops, the cabbage, cauliflower, turnip, 
etc. It is caused by a very minute or- 
ganism belonging to the group Myxo- 
675 
mycetes, commonly referred to as the 
slime moulds. The technical name of the 
organism causing this disease is Plasmo- 
diophora brassicae. This disease occurs 
in various sections of the Northwest, but 
cannot be considered to be a very common 
trouble. The knotty swellings or club- 
shaped enlargements (Fig. 1) resulting 
Ore xy. Sto. a 
Fig. 1. Cabbage Plant Affected With 
Club Root. 
from the invasion of roots by this fungus 
prevent the normal growth of head or 
root and gradually kill the plant. 
When once established in the soil, the 
fungus will live for several years. Cer- 
tain weeds, shepherd’s purse and hedge 
mustard, are good hosts and doubtless 
furnish opportunity for the disease to 
perpetuate itself and to spread. 
Control 
Care must be taken to keep the seed 
beds clean. Destroy all refuse from dis- 
eased plants. Do not allow such material 
to get into the compost heap. Practice 
rotation with crops not included in this 
group of plants, and keep the weeds down. 
