. Cooperative economic insect report. Beneficial insects; Insect pests. Damage to Violet Infestations have increased in Germany since 1950. They have reached about 30 percent in plantings near Berlin, where they may cause loss of flower production. Heavy infestations cause distortion and dwarfing and sometimes death of the plant. Living pupae were found in the leaves of a violet plant in the mails from England at Hoboken, New Jersey, in 1954. Distribution: Widely distributed throughout Europe, being recorded in Sweden, Denmark, Hungary, Italy, Rumania, France, Portugal, Great Britain and Germa
. Cooperative economic insect report. Beneficial insects; Insect pests. Damage to Violet Infestations have increased in Germany since 1950. They have reached about 30 percent in plantings near Berlin, where they may cause loss of flower production. Heavy infestations cause distortion and dwarfing and sometimes death of the plant. Living pupae were found in the leaves of a violet plant in the mails from England at Hoboken, New Jersey, in 1954. Distribution: Widely distributed throughout Europe, being recorded in Sweden, Denmark, Hungary, Italy, Rumania, France, Portugal, Great Britain and Germany. Also known to occur in Algeria, Morocco and Egypt in North Africa. Hosts: Cultivated and wild Viola, including violets and pansies. Life History and Habits: Females begin emerging from overwintering cocoons in the spring. They live from 3 days to one week and lay up to 98 eggs each. Eggs are laid in the leaf tissue along the margins of the older outer leaves or within the rolled edges of the younger leaves. Eggs laid in exposed dry positions die. Larvae hatch in 6 to 8 days at 68° F. and cause formation of hairy galls on the shoots and leaves. They feed gregariously inside the leaf, as many as 24 larvae being found in a single gall. There are generally 4 larval molts in France. The usual larval period lasts about 6 weeks except in the overwintering generation. The total larval period varies from a minimum of 27 days in the spring and summer to a maximum of about 7 months in the overwintering generation. The mature larva spins a cocoon within the gall, although it may spin a cocoon elsewhere if. General Distribution of Violet Leaf Midge * Also called Violet Leaf Rolling Gall Midge (Itonididae, Diptera). No. 67 of Series. 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 United States. Animal and Plant Heal
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