APPLE DISEASES 
of the surrounding ones. The crown and 
large roots of these trees had been left 
exposed for two seasons with no apparent 
ill effect, the earth being thrown back 
over them, however, each winter. A trial 
of these methods is recommended. It may 
be that simple root exposure would help 
to check the disease or that thorough 
cutting out and sterilization would stop 
its progress, but so little experimentation 
has been done along these lines that def- 
inite assurances of success cannot be 
made. 
Bibliography 
1910. Washington Experiment Station, 
Bulletin No. 3, Special Series. 
1911. Pennsylvania Experiment Station, 
Bulletin No. 152. 
1911. Arkansas Experiment Station, Bul- 
letin No. 71. 
1911. Ohio Experiment Station, Bulletin 
No. 214. 
1912. Oregon Experiment Station, Crop 
Pest Report, 1911-12. 
California Com. Hort., II No. 6. 
California Fruit Growers’ Report, 1910, 
Page 98. 
1901. Oklahoma 
Bulletin No. 49. 
1903. Washington Experiment Station, 
Bulletin No. 59. 
A New Disease on Apples 
A new disease on apples has been re- 
ported by the Pennsylvania State College* 
and described as follows: 
“This disease is apparently physiolog- 
ical, and appears most conspicuously as 
an affection of the twigs of the current 
season’s growth, though it is not confined 
to them. The twigs lose their normal 
color and become dull and of a rather 
blistered and mottled appearance at first. 
At a casual glance the effect somewhat re- 
sembles that produced by an incrustation 
of the San Jose scale. Immediately under 
the epidermis of the diseased areas and 
extending about half way to the cambium, 
in the early stages, there are numerous 
small, brown spots or pits where the tis- 
sues are dead or dying. Later, on the 
surface, the epidermis usually cracks 
Experiment Station, 
* Pennsylvania State College Report, 1910-11. 
475 
around and over the diseased spots and 
they become rough, dark, and rather scab- 
like, and are usually slightly sunken 
through the drying out and death of the 
tissues underneath. In some cases the 
cracks may go deeper and involve the 
wood. The leaves are also affected sooner 
or later, probably through the girdling of 
the twigs below them. They turn brown, 
dry out and crumble, beginning at their 
tips and outer margins. In time, the 
twig, limb or whole tree may be killed. 
“The disease usually becomes well de- 
veloped and conspicuous by the middle or 
latter part of August.” 
No remedy is suggested but the indica- 
tions point to fertilizer trouble. 
New Hampshire Fruit Spot 
See Cylundrosporium Fruit Sopot. 
New York Apple Tree Canker 
See Black Rot. 
Orange Rust 
See Coryneum Leaf Spot. 
PENECILLIUM. See Blue Mould. 
Pink Rot 
Cephalothecitum roseum 
This fungus has been found to accom- 
pany scab and seems to gain entrance to 
the apple at points of rupture in the skin 
caused by the scab. It is called “pink 
rot’ on account of the color of the spots 
as the fungus matures. Its first appear- 
ance, however, is that of a thin gray film 
of mildew. 
It develops both in and out of storage. 
The rot has been very destructive at times 
in New York. The method of control is 
the same as for scab, which see. 
References 
1902. Cornell Bulletin No. 207. 
1903. New York Bulletin No. 235. 
Poms Brieuwr. See Blight under Pear. 
Powdery Mildew 
Sphaerotheca mali 
H. 8. Jackson 
The apple powdery mildew is a com- 
mon disease in nearly all fruit sections of 
the Northwest. 
This disease was formerly considered 
as most serious on nursery stock, but un- 
