. Cooperative economic insect report. Insect pests Control United States Periodicals. 824 Life History and Habits: Adult emergence from overwintering puparia begins in April on the European Continent. The eggs are deposited singly, about one inch from the asparagus tip, to 1 mm. deep in the scales. Hatching occurs in a few days and the larvae begin to tunnel down the stems feeding on the tissues. One shoot may contain upwards of 20 larvae and pupae. The galleries of the larvae occasionally go to the roots but never penetrate them. Impeded and distorted growth of the stem indicates the pres
. Cooperative economic insect report. Insect pests Control United States Periodicals. 824 Life History and Habits: Adult emergence from overwintering puparia begins in April on the European Continent. The eggs are deposited singly, about one inch from the asparagus tip, to 1 mm. deep in the scales. Hatching occurs in a few days and the larvae begin to tunnel down the stems feeding on the tissues. One shoot may contain upwards of 20 larvae and pupae. The galleries of the larvae occasionally go to the roots but never penetrate them. Impeded and distorted growth of the stem indicates the presence of the insect. Just before pupation, the larva ascends the stem without making a new gallery to just above the soil level then excavates a passage to the surface without breaking the epidermis. The adult will emerge at this point. Larvae mature in 3 to 4 weeks and then pupate, head upwards, about 2 to 5 inches below the surface of the soil, though sometimes they will pupate above the surface. There is only one generation a year, but due to the lengthy period of emergence, newly- hatched larvae and pupae may be found at the same time, even in the same stem. Asparagus beds that are surrounded by high vegetation are sometimes protected from attack, since the females prefer to lay eggs in clean-cultivated asparagus. Description: The adult is similar in appearance to the celery fly, Acidia heraclei , but is slightly larger, and the black markings on the wings are, more extensive. The body is almost entirely gray; head yellow, face ferruginous, palps testaceous, antennae brownish, frons chocolate-brown, eyes red. Thorax clear gray with three long, black longitudinal stripes; shoulders yellowish. Wings are characteristic (see illustration). Abdomen black. Adult 5-7 mm. long. Eggs white and oval, mm. long. Mature larva 7-9 mm. long, yellowish-white in color, front segments slightly tapered with two hooks; posterior end flattened with brown plate surrounding two posterior, fork
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Keywords: ., bo, bookcentury1900, bookcollectionbiodiversity, bookleafnumber20
