444 
determine. The ideal time would be to 
spray before the first fall rains. In prac- 
tically all sections of the Northwest 
where this disease occurs this would be 
before the fruit is picked, and it is found 
somewhat objectionable to use Bordeaux 
mixture before the fruit is picked because 
of the slight deposit on the fruit. 
In many of the older orchards where 
the trees are close and it is found neces- 
sary to use props in case of a heavy 
erop, it is often impossible to get 
through the orchard with a spray ma- 
chine before the crop is picked without 
knocking off considerable fruit. On the 
other hand many growers complain that, 
on account of unfavorable weather con- 
ditions which frequently prevail follow- 
ing picking, they are often unable to 
spray in the fall as recommended—until 
it is too late to be of any value—if the 
Spraying is delayed until after picking 
is done. Others complain that on ac- 
count of the press of work incident to 
picking and packing a large crop even 
in seasons of favorable weather condi- 
tions, they have not time to spray until 
the proper season is past. On the other 
hand it is evident that trees must be 
protected with a fungicide during the 
fall of the year in order to prevent in- 
fection. 
Experiments which have been conduct- 
ed to date indicate that good results are 
obtained by spraying once with Bor- 
deaux mixture 4-4-50 before the first fall 
rains, or about the middle of September, 
following by another application, using 
Bordeaux mixture 6-6-50, after the fruit 
is picked. 
It is possible that where growers give 
a late spray for codling moth that a 
combination spray could be applied, using 
Bordeaux mixture 4-4-50 and arsenate of 
lead, two pounds to 50 gallons, in the 
latter part of August. This would be 
used to take the place of the spraying 
suggested in the middle of September. 
It has not been fully demonstrated 
whether this suggestion will prove satis- 
factory in general practice. It is worthy 
of trial, however, by interested growers, 
and may prove to be the most satis- 
ENCYCLOPEDIA OF PRACTICAL HORTICULTURE 
factory solution of the problem for the 
grower who wishes to keep a compara- 
tively clean orchard protected from in- 
fection by this disease 
In orchards where the disease has ob. 
tained a foothold, however, the recom. 
mendations aS given under 
mary should be followed. For other 
supplementary methods of control gee 
Summary of Recommendations. 
SUMMARY 
Life History Investigations 
1. A disease known throughout the 
Northwest as Apple Tree Anthracnose 
or Black Spot Canker is caused by a 
fungus which, in the conidial stage, is 
a parasite causing cankers on _ the 
branches of apple and pear trees. 
the sum- 
2. The cankers caused by this fungus 
cause the death of the tissue of the bark 
in which it develops and of the cam- 
bium, and spreads to some extent to the 
sapwood beneath. 
3. Infection occurs in the fall and 
early winter and the cankers develop 
slowly during the early part of the 
dormant season and spread rapidly in 
the early spring, reaching their full size 
when the cambium resumes activity in 
the spring. 
4. The fungus matures slowly during 
the summer in the dead bark of the 
cankers thus formed. Spores are pro- 
duced in acervuli characteristic of the 
genera Gloeosporium or Myzosporium of 
the Fungi Imperfecti. 
5. This conidial form has been named 
by Cordley, Gloeosporium malicorticis. 
6. The fungus continues to develop 
in the dead bark of old cankers as a 
saprophyte and: produces in the late 
summer or fall, one year after the ma- 
turity of the conidial stage, an ascosporic 
form having the characteristics of the 
family Mollisiaceae of the Discomycetes. 
7. The connection of this Ascomycete 
with the conidial stage has been proved 
by inoculation experiments. 
8. This has been made the type of a 
suggested new genus called Neofabraed. 
The proper scientific mame for the 
