. Annual report of the Commissioner of Agriculture ... Agriculture -- New York (State). THE PEAK PSYLLA* P. J. PARROTT and H. E. HODGKISS. The psylla is one of the principal enemies of pear orchards, and in many localities of the State it is the most troublesome if not the most destructive insect pest of this fruit. It has ruined many crops of pears and has so weakened large numbers of trees that they have easily succumbed to winter-killing. NATURE OF INJURY. Severe damages to pear trees occur during periods of the super- abundance of the psylla. The injuries are due primarily to the loss. Fig
. Annual report of the Commissioner of Agriculture ... Agriculture -- New York (State). THE PEAK PSYLLA* P. J. PARROTT and H. E. HODGKISS. The psylla is one of the principal enemies of pear orchards, and in many localities of the State it is the most troublesome if not the most destructive insect pest of this fruit. It has ruined many crops of pears and has so weakened large numbers of trees that they have easily succumbed to winter-killing. NATURE OF INJURY. Severe damages to pear trees occur during periods of the super- abundance of the psylla. The injuries are due primarily to the loss. Fig. 26.—Leaf cluster showing nature of injury by nymphs of pear psylla. of plant juices extracted by myriads of the tiny insects which feed on the stems of leaves and fruits. The work of the first brood of larvae or nymphs during the latter part of May or early in June, at the axils of the tender leaves and young fruits or on the under sides * Reprint of Circular No. 20, January 22, 1913. [353] 23. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original New York (State). Dept. of Agriculture; New York State Agricultural Experiment Station; Cornell University. Agricultural Experiment Station. Albany : State of New York, Dept. of Agriculture
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Keywords: ., bookauthornewyorkstateagricultu, bookcentury1800, bookdecade1890
