468 
concentric arrangement. Proceeding from 
the innermost cavities toward the edge 
of the spot the cavities become smaller, 
none at all being found near the edge of 
the diseased tissue. 
Upon sectioning through a _ diseased 
spot the flesh of the fruit is seen to be 
rotten, brownish and soft, not black or 
dry, as is the case with the volutella rot. 
Microscopic examination shows the dis- 
eased tissue to be thoroughly invaded 
with a thin branching mycelium. 
When this disease is upon twigs, the 
terminal portions of recent growth die, 
the bark shrinks and shrivels, turns black 
and at the line of demarkation between 
diseased and healthy tissue cracks. The 
general appearance of such a twig is 
much like that caused by the fire blight, 
but is readily distinguished by the pres- 
ence of very numerous, minute, pimple- 
like pustules, fruiting cavities distri- 
buted over the dead part. 
The significance of this fungus upon 
twigs is twofold: (1) As a cause of the 
twig blight; (2) as a source of infective 
material, spores, to transmit the rot to 
the fruit. 
Treatment 
Spraying coupled with careful pruning 
out and burning of diseased twigs and 
branches will doubtless serve as a means 
of control of this rot, both of branches 
and fruit. 
F. L. STEVENS, 
West Raleigh, N. C. 
Fruit Spot 
Phoma pomi Passer 
This disease is of very common occur- 
rence in New Hampshire and is found as 
far south as Maryland and Virginia and 
as far west as Michigan. It is not so 
destructive as the scab, but often causes 
otherwise perfect fruit to go as seconds. 
It is found on almost every variety of 
apple, but Baldwins and Tolman Sweets 
are especially susceptible. The disease 
appears about the middle of August. At 
this time it may be seen as spots of a 
deeper red on the colored surface of the 
apple and of a darker green on the lighter 
portion. As the season advances, the 
ENCYCLOPEDIA OF PRACTICAL HORTICULTURE 
spots become more prominent. They be- 
come slightly sunken and more highly 
colored. Numerous black specks appear, 
sometimes causing the center of the spot 
to have an almost uniformly black ap- 
pearance. The tissue beneath the spot 
is rendered brown and corky to a depth 
of several cells. Cold storage seems to 
check the development of the spots, but 
in cellar storage they often become more 
Big. 1. 
(New slampulifte Experiment Station). 
Fruit Spot. 
sunken and spread deeper into the tissue 
of the apple. They become brown and are 
much enlarged, sometimes attaining a 
diameter of one-half inch. 
Recent experiments* have shown that 
the fungus causing the fruit spot of 
apples-is also responsible for a similar 
spot on quinces known as “quince 
blotch.” The disease may spread from 
one host to the other. 
Treatment 
The fungus does not attack the apples 
until they are nearly grown. Conse- 
quently, sprayings made in late June or 
early July are usually as effective if not 
more so than those made earlier in the 
year. However, orchards that have re- 
ceived three and four sprayings for scab 
will not usually require later spraying 
for fruit spot. Both Bordeaux and lime- 
sulphur have given satisfactory results. 
CHARLES BROOKS 
and Black, Caroline A. 
Phyto- 
* Brooks, Charles, 
Apple Fruit Spot and A i Blotch. 
pathology II, 63-73, 1912. 
