870 
fruits. Conspicuous black spots which 
are slightly sunken are formed on the 
leaf stalks and petioles and also on the 
fruit stems. Here the spots are black and 
from one-fourth to one-half inch long. 
On the fruit black spots resembling fly- 
specks are formed. 
On the young canes the disease pro- 
duces only a slight discoloration; it oc- 
curs only upon young canes of the current 
year’s growth, and is very difficult to 
detect. 
Where plants are in partial shade they 
are not as seriously attacked. Older 
plantations are found to be more seriously 
affected than more recent plantings. 
Cause 
This disease is caused by a fungus 
known technically as Pseudopeziza ribis. 
The fungus exists in two spore stages. In 
the spots on the leaves, petioles and canes, 
the summer spores are produced in pecu- 
liar fruiting structures known as acer- 
vuli; these are doubtless disseminated by 
wind and spattering rain, and when com- 
ing to rest upon any part of the plant 
grow into the tissues and cause new 
spots. 
It has been proved that the fungus ma- 
tures on the stems, and it is possible that 
it winters over on the canes in this condi- 
tion. 
It is certain that the fungus is carried 
over the winter by the foliage, which lies 
on the ground. 
Treatment 
The first infection results from the 
dissemination of spores from the dead 
leaves of the previous season, and any 
method of destroying these leaves might 
tend to reduce the seriousness of the 
attack. It would be advisable, there- 
fore, to plow early, before the leaves 
come out in the spring. in order to bury 
the dead leaves. Where practicable, rak- 
ing and burning the leaves would have 
the same result and would probably be 
more effective. A dormant spraying to- 
ward spring, to prevent any further de- 
velopment of the summer spores on the 
canes, would be advisable. Use the Bor- 
deaux mixture 5-5-50. Spray again when 
the leaves unfold and repeat at intervals 
ENCYCLOPEDIA OF PRACTICAL HORTICULTURE 
of ten days until the fruit is two-thirds 
grown, avoiding the blossoming period. 
If summer rains are abundant it may be 
found profitable to spray once or twice 
after the fruit is gathered. 
Brack Kynor. See under Cherry Dis- 
eases. 
Cane Blight 
Neciria cinnabarina (Tode) Fr. 
This is a very serious disease whenever 
stools are attacked by it. The fungus sur- 
vives by its threads in the tissues of the 
stool and upon the death of the canes de- 
velops as a bright pink mass of the fun- 
gus upon dead parts. While spraying 
may, and surely must, keep down the 
risk of infection, whenever stools show 
attacks by dying of a part of the canes 
and the development of this fungus these 
infected stools are doomed and should be 
removed and burned. A. D. Srenpy 
Reference 
Duggar, Fungus Diseases of Plants. 
Currant Blight, Currant Cane Blight, 
Currant Cane Necrosis 
Botryosphaeria rubis 
An Old, Obscure Disease 
More than twenty years ago, a disease 
was discovered which has become today 
a very destructive trouble in the currant 
plantations of the Hudson valley, New 
York. The cause of this disease re- 
mained long unknown; but careful study 
by botanists of the Geneva and 
Cornell stations proved it to be due to a 
fungus which has three distinct spore 
forms Of these, the basal form is Botry- 
osphaeria ribis, so that this stands as the 
scientific name of the fungus which 
causes currant blight, currant cane blight, 
or currant cane necrosis. Usually, the 
discovery of the cause of a disease soon 
leads to a remedy, but in this case no 
preventive or remedial treatment can yet 
be recommended. 
Symptoms of the Disease 
On certain canes, or portions of the 
canes, the leaves wilt, turn brown and 
die. An affected cane will show a sec- 
tion of dead wood from one to four 
inches long where the bark has been 
killed and wood and pith invaded by the 
