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Show INSECT DOING CONSIDERABLE DAMAGE TO PEAR ORCHARDS IN EASTERN STATES Productiveness of Many Trees in Fruit Growing Sections Has Been Greatly Reduced by Thrips, a New Pest Most Effec- ... tive Control Is Spraying. cultivation, fertilizers, pruning and spraying for other insects and diseases dis-eases should be carefully considered In order that the most favorable conditions con-ditions for recovery to health and productiveness may be afforded tc the trees. ; The thrips is a difficult pest to combat com-bat because of the nature and suddenness sudden-ness of its attacks. Spraying is the most efficient method of control. The period for effective spraying is during the time when the buds are breaking and until they are entirely opened at the tips. The most promising spraying spray-ing mixtures are the nicotine preparations prep-arations in combination with kerosene emulsion or soap. Two or three applications ap-plications on successive days during the past year largely prevented important im-portant injuries to pear trees. The physical features of the locations of the orchar3, such as the direction and elevation of the slopes of the land, and character of the soil, have a marked influence on the development of the buds and the time of blossoming. blossom-ing. The time for effective spraying will therefore vary with Individual orchards. (By P. J. PARROTT.) For a number of years pear blossoms blos-soms In orchards In the state of New York and other parts of the east have . blighted, resulting in more or less extensive ex-tensive losses in fruit yields. Careful studies during the past fear have shown that the injury Is caused by the pear thrips, a new jrchard pest, which has attracted con-liderable con-liderable attention in recent years in California because of its destructlve-aess destructlve-aess to various deciduous fruits. The adult thrips, which is largely responsible for the injuries to the :rees, is a small, darkish brown, winged insect measuring about one-.wentieth one-.wentieth of an inch in length. It appears ap-pears In destructive numbers when .he buds are opening, attacking the :enderest of the flower parts. The ;ggs are mostly deposited beneath the epidermis of the blossom and fruit items. Platching takes place within a 'ew days, and the larvae seek prefer-ibly prefer-ibly the calyx cups, undersides of :a!yces, and"- the folds or under sur-'aces sur-'aces of the tender,, expanding leaves. The larvae feed for about two weeks md drop to the ground, in which they orm a protecting cell. In this cell -he insect completes its transforma-ions transforma-ions and emerges from the ground In he spring as an adult. The thrips is tingle brooded; and the most active ind destructive stages are coincident vith the period that includes the life svents of the swelling and opening of he buds and dropping of blossoms ind calyces. Injuries by the thrips in the Hudson ralley have apparently occurred over i period of five years. During the last three years fruitgrowers gyner-illy gyner-illy have noticed blighting of blossom ilusters of pear trees, although the lature of the causal agent seems not o have been suspected. According to Adult Pear Thrlfia. itatements of fruitgrowers the most levere attack of the thrips occurred luring 1910, when the pear crop in nany orchards was much reduced. 3esides losses In yields the trees were ieriously checked by injuries to leaf juds and leaf clusters; and in som Drchards the season was much advanced ad-vanced before the trees presented normal nor-mal conditions of growth. The pro- ' - - iuctlveness of pear orchards during 1911 was greater than the preceding year, but blighting of blossom clusters was general and orchards suffered iosses In yields according to the severity sever-ity of the attacks by the thrips. Severe attacks by the thrips are a serious drain on the vitality and pro-luctlveness pro-luctlveness of the trees. In their weakened state they are also more subject to Injuries by adverse weather 3r environment, and to attacks by various wood-boring Insects. The needs of the orchard with respect to j |