Chapter III · PEAR CULTURE (continued 2)

Several scale insects, other than San Jose scale, are more or less pestiferous in the pear-orchards of this State; commonest of these is the oyster-shell, which not infrequently does serious damage to young and unhealthy trees. The scurfy scale found chiefly on the apple sometimes becomes a pest on the pear. A hemispherical scale, about one-twelfth of an inch in length, known as the terrapin scale, now and then infests the pear, but is seldom if ever harmful. As a rule, the treatment for San Jose scale keeps all other scales in check, but all are more difficult to kill than the San Jose and in cases of troublesome infestations may require drastic treatment with a contact insecticide.

A great number of chewing insects, as distinguished from sucking insects, defoliate the pear when given an opportunity, but are kept in check by the treatment for codling moth. The much-dreaded browntail moth and gypsy moth now have a foothold in the State, but as yet can hardly be called pests although their advent threatens the pear industry as it does all other orchard industries. The bud-moth, seldom seen in well-cared-for orchards, is sometimes a vexatious visitor in pear-orchards. Three species of caterpillars, all most striking in appearance, the larval stages of tussock moths, infest pear-trees. These are the white-marked tussock moth, the rusty tussock moth, and the definite-marked tussock moth.

The pear-tree has its share of borers. A small, dark brown beetle, about one-third of an inch in length, the apple twig-borer, sometimes does considerable damage to young shoots of the pear. The flat-headed apple-tree borer works in the sap wood of the pear as in the apple. The shot-hole borer, a tiny insect, eats a small round hole in the trunk of the pear, as it does also in several fruits, but does little damage except in devitalized trees. The shot-borer, a tiny black beetle, one-tenth of an inch long, bores into twigs or small branches and sooner or later causes their death. None of these borers are very harmful on the pear in New York, but all must be reckoned with occasionally. All are difficult to control.

The pear thrips attack the newly opening flower- and leaf-buds and when the insect, a small winged creature with sucking mouth-parts, is abundant much damage is done. This pest in New York is chiefly confined to the Hudson River Valley. The European grain aphis, closely related to the destructive apple aphis, is sometimes a serious pest on pears. Both of these pests are comparatively easily controlled by timely applications of contact insecticides.

Lastly, there are several chewing insects which feed on the leaves of the pear, which, unless checked, sometimes become major pests for a season or two in an orchard here and there. All of them, fortunately, are controlled by the arsenical poisons which are necessary to keep the codling moth down. The pests are: Cigar case-bearer, green fruit worm, pistol case-bearer, and oblique-banded leaf-roller. With these, as with most of the other pests of the pear, cultivation to keep down all foreign vegetation, and orchard sanitation, consisting chiefly of the destruction of infested fruit, foliage, or wood, are essential preventives.