THE PEARS OF NEW YORK 117 
in the sun 1s usually sufficient to keep the fungus in check, but a late 
application of lime and sulphur is often necessary. 
Black mold (Fumago vagans Fr.), a fungus which grows in the honey- 
dew exuded by the nymphs of the pear-psylla, sometimes causes a sooty 
covering of the pears which spoils their sale. Twigs and leaves are also 
covered with thin superficial growth of the fungus somewhat to the detri- 
ment of growth. The remedy is obvious — control the psylla. 
Pink-rot (Cephalothecium roseum Cda.) sometimes does much damage 
to pears in common or cold storage. The fungus seems able to enter 
the skin of pears only through injuries, and when reasonable care is used 
in handling the fruit the rot does little damage. Not infrequently it is 
found on fruits unpicked, having entered the skin through ruptures made 
by pear-scab, black-spot, or other fungi. This, of course, seldom happens 
in well-sprayed orchards. 
INSECTS ATTACKING THE PEAR 
Several insect pests are very destructive to pear-trees, as many more 
are often troublesome, while perhaps in addition to the dozen that must 
always or occasionally be combatted some thirty or forty more have been 
listed as pear-pests. Young pear-trees are very susceptible to injuries 
of any kind and if beset by any of the common insect pests do not prosper. 
As the trees come to maturity, life and vigor of the tree may not be endan- 
gered by any but two or three of the worst pests, but the crop is always 
cut short by infestations of insects on any part of the plant which interferes 
with the normal life of the tree. The pests most destructive to the pear 
in New York, about in order of importance, are San Jose scale, psylla, 
codling-moth, pear-slug, and pear-leaf blister-mite. 
San Jose scale (Aspidiotus perniciosus Comstock) is particularly harmful 
to tree and fruit of the pear. The pears, possibly, are malformed more 
and show the scales with their discoloration more plainly than the product 
of any other fruit-tree. A scale-infested pear-tree is easily recognized. 
Dead and dying twigs or branches and moribund trees are evidences of 
the dreaded pest. Examination shows the moribund parts to be covered 
with myriads of minute scales which give the infected bark a scurfy, ashy 
look. A reddish discoloration is discovered if the bark be cut or scraped. 
A foothold gained on trunk or branch, fruit and foliage are soon infected. 
Reproduction is continuous throughout the summer, and the scales increase 
by leaps and bounds. Smooth-barked young trees succumb within three 
