APPLE DISHASES 
ent on the life history of the fungus 
causing the disease Since the fungus 
winters over on the tallen leaves, 1t would 
be advisable to destroy all such leaves 
before blossoming time The usual 1ecom- 
mendation 1s to plow the oichards early 
in the spring before the trees blossom, in 
order to bury the leaves in which the 
ascogenous spore stage 1s developed The- 
oretically, the best way to destroy the 
leaves would be to rake and burn them 
before plowing, but pathologists have hesi- 
tated to make this recommendation on the 
grounds of impracticability 
In any case, the trees should be given 
at least three sprayings during the spring 
The first application should be made as 
the blossom buds begin to separate in the 
cluster and show color, the second should 
be applied just after the petals fall, fol- 
lowed by a third application 10 days or 
two weeks later. Should the third appli- 
cation be followed by prolonged rains, a 
fourth may be found profitable 
Formerly Bordeaux mixture was used 
almost entirely as a preventive of scab, 
but in certain sections of this country, 
notably under the climatic conditions 
prevalent in the Northwest, the injury 
from russeting has been so severe as to 
make its use prohibitive. On this ac- 
count lime-sulphur has largely supplanted 
Bordeaux as a remedy for this disease 
In the Willamette valley repeated ex- 
periments conducted under the direction 
of Prof. A B Cordley have shown that 
lime-sulphur (stock solution 30 degrees 
Baime) diluted one to 30 with water, 
app ed in three sprayings as recom- 
mer “7d above, has given excellent results 
in th control of apple scab This method 
is ne used by most growers in the Will- 
amette illey. 
The fall applications of Bordeaux mix- 
ture recommended for the control of the 
apple tree anthracnose, will doubtless 
have a tendency to reduce the spread of 
the apple scab in the fall and may prove 
to have a beneficial effect in retarding 
the development of the ascogenous stage 
in the leaves which fall to the ground 
coated with the spray. 
489 
Bibliography 
1891 Ohio Experiment Station, Bulletin 
Vol IV, No 9 
1897 Ohio Experiment Station, Bulletin 
No 79 
1899 Ohio Experiment Station, Bulletin 
No. 111. 
1909 Duggar, Fungus Diseases of Plants. 
1910 Ohio Experiment Station, Bulletin 
No 214 
1912 Montana Experiment Station, Cur- 
cular No 17 
Seurf 
Phyllosticta prunicola Sacc. 
The branch scurf fungus is believed to 
occur in Ohio This causes roughening 
of the bark, but no statements can now 
be made as to its possible seriousness. 
A D Ssxpy 
SHOT-HOLE Funeus. See Leaf Spot 
Silver Leaf 
Stereum purpureum, Pers. 
Attacks a variety of plants in Europe 
and reported in 1910 from Nova Scotia. 
Trees affected may be cherry, plum, al- 
mond, apple or pear The leaves have a 
peculiar silvery appearance or milky- 
white gloss on the upper surface which 
appears brittle when bent Branches 
attacked die after one or two years The 
whole tree eventually succumbs 
Remedy 
Cut off affected branches as fast as they 
appear and burn. Paint all wounds with 
white lead 
Sort Ror (Sclerotinia fructigina). See 
Brown Rot 
Sooty Blotch and Fly Speck 
Leptotherium Pomi (Mont. & Fr.) Sacc 
The sooty blotch and the fly speck of 
the apple were formerly thought to be 
caused by two different fungi, but a re- 
cent writer* claims that one fungus is 
responsible for the two diseases. The 
names given to these two effects charac- 
terize their appearance. The former pro- 
duces blotches one-eighth to one-half inch 
in diameter on the fruit (Fig. 1) and the 
*B F Floyd in Duggar’s Fungus Diseases of 
Plants 
