Insect Pests of the Horticulturalist: Their Nature and Control

Abstract

The three pests described in this work are among the most serious enemies with which the commercial grower has to contend. Unfortunately, no really adequate measures for controlling any one of them have so far been discovered. The celery-fly, in its larval stage, mines the leaves of both celery and parsnip. Owing to the concealed mode of life pursued during this period of its development, the insect is exceedingly difficult to kill by means of any feasible insecticide. Mr. J. C. M. Gardner, who is responsible for the section on the celery-fly, suggests the use of a spray containing chlororthocresol as a deterrent preventing the insect from egg-laying on the plant. He also suggests that a certain number of plants (presumably he means those of the parsnip) should be left in the ground to continue growth for a second year. Plants thus left were found, in a private garden, to be heavily infested, while neighbouring seedlings were only slightly attacked. It is, therefore, possible that the two-year-old plants might serve as a trap crop which, when heavily infested, could be pulled up and burnt. The idea, however, needs testing thoroughly on a practical scale.

Insect Pests of the Horticulturalist: Their Nature and Control.

By K. M. Smith J. C. M. Gardner. Vol. 1: Onion, Carrot, and Celery Flies. Pp. vi + 76 + plates. (London: Benn Brothers, Ltd., 1922.) 7s. 6d. net.