APPLE DISEASES 
by the proper use of Bordeaux mixture, 
the remedy recommended at the end of 
this paragraph. While a certain number 
of applications are recommended, more 
will have to be given if the season is 
wet. The object should be to keep the 
trees covered with the mixture from 
the first until the last spraying. If the 
mixture is washed off the tree the dis- 
ease will have an opportunity of devel- 
oping and it is difficult to check it, if 
it begins to spread. 
Remedy 
Spray with copper sulphate solution 
(one pound copper sulphate to 25 gal- 
lons water) or with Bordeaux mixture 
before the buds start, or when they be- 
gin to break; and with Bordeaux mix- 
ture, just before blossoms open; soon 
after blossoms fall and two or three 
times after at intervals of from 10 to 15 
days. The first three sprayings are the 
most important. W. T. Macoun, 
Ottawa, Canada. 
Blight 
Bacillus amylovorus (Burrill) De Toni. 
FrrE BuiicHt, Prar BuicuHt, Twice 
BuiiecHt. See under Pear. 
Blister Canker 
Nummularia discreta Tul. 
The disease is sometimes known as 
“Illinois Canker,” since it was first ob- 
served as particularly destructive in that 
state. It seems to be less destructive 
in New England than the black rot 
and European cankers. It has a char- 
acteristic appearance that readily dis- 
tinguishes it from either of these dis- 
eases. (See Fig. 1.) It is usually found 
on the larger: limbs, and sometimes at- 
tacks the trunk. Old cankers are often 
a foot or more in length. The fungus 
attacks the wood as well as the bark. 
In the early stages of the disease the 
bark is brown and slightly sunken and 
usually set off from the healthy bark by 
a distinct boundary. As the season ad- 
vances circular fungous masses known 
as stromata develop on the diseased area. 
They are formed beneath the bark, but 
soon break through to the surface, fur- 
nishing the most characteristic feature 
451 
Fig. 1. Blister Canker of Apple. The bark has 
been removed from the upper portion show- 
ing Fe circular markings produced in the 
wood. 
of the disease. The stromata are firmly 
fastened to the wood by means of a hard 
ring of fungous tissue, so that they re- 
main attached to it even after the bark 
has fallen away. Summer spores are 
produced on the surface of the stroma. 
Later in the season, numerous flask- 
shaped perithecia are formed within the 
stroma, but opening on its surface. These 
produce many club-shaped asci, each con- 
taining eight spherical, brown spores. 
Treatment 
The fungus seems to be dependent 
upon wounds for entrance to the host 
tissue. The best method of treatment 
is found in avoiding unnecessary in- 
juries to the tree and in the proper care 
of all wounds. All cankered limbs should 
be destroyed. CHARLES Brooks, 
Durham, N. H. 
BLOSSOM BLIGHT. See Blight under 
Pear. 
Bloteh 
Phyllosticta solitaria E. & E. 
The blotch is caused by a _ fungus 
which lives parasitically upon. the fruit, 
twigs and leaves of the apple. 
