THE PEARS OF NEW YORK II5 
lime and sulphur at the summer strength, if applied annually, are usually 
sufficient to control the fungus. The first of these applications should be 
made when the blossoms show color, a few days before they open. The 
second should be put on when most of the petals have fallen. In seasons 
favorable to the scab, a third application two weeks after the second may 
be the means of saving the crop. The spread of the disease is greatly 
favored by damp warm weather. 
Pear-growers are plagued by two leaf-spots, one of which is also known 
as leaf-blight. The leaf-spot here to be discussed (Mycospherella sentina 
(Fr.) Schroet.) is sometimes called the ashy leaf-spot. The disease is not 
often seriously troublesome in New York, but is capable of doing great 
damage in both the nursery and orchard. The spots which give name to 
the disease are conspicuous enough, but even when present in great numbers 
are often not seen by the pear-grower until there is a premature dropping 
of the leaves in August or earlier. The trees often put out new growths, 
with the result that the wood does not ripen and the tree is left in no con- 
dition to stand the cold of winter in this northern climate. 
As with nearly all diseases of plants, some varieties suffer more than 
others. Sheldon, Seckel, and Flemish Beauty are more injured than 
Kieffer, Lawrence, and Mount Vernon. Nursery stock is more often 
injured the second than the first year set. Only the leaves suffer. The 
fungus first shows its work in minute purplish spots on the upper surface 
of the leaf. The mature spots measure about one-sixth of an inch in diam- 
eter, are angular in shape, with well-defined margins, and have an outer 
zone of brownish-purple, with a grayish center. Late in the season, dots, 
the spore-cases of the fungus, appear in the gray central area. The fungus 
passes the winter in diseased leaves which fall to the ground in late summer. 
From these leaves spores are discharged into the air to be carried to the 
leaves after growth begins in the spring. The disease is usually controlled 
by the sprays necessary every year to keep pear-scab in submission. In 
the nursery, two-year-old trees are sprayed just after the new leaves open 
and twice thereafter at two-week intervals. One-year-olds seldom need 
to be sprayed. 
Leaf-blight (Fabrea maculata (Lev.) Atk.) is a common and destruc- 
tive fungus in pear-nurseries in New York and is sometimes troublesome 
in orchards. The quince suffers even more than the pear from this fungus. 
In the nursery, leaves and twigs are attacked, and in the orchard the pears 
themselves sometimes suffer, The disease appears in the spring as minute, 
