Pine hawk moth (Hyloicus pinastri L.)From: Kolk A., Starzyk J. R., 1996: The Atlas of Forest Insect Pests Occurrence: The pine hawk moth occurs over the whole Europe. In Poland it is observed mostly in western part of the country. Host Plants: The Scots pine is a major host plant species of the pine hawk moth. It also sporadically feed on spruce, fir and larch. Morphology: Moths are 37-40 mm long with a 60-90 mm wingspan. The first wings generally are grayish with a brown hue and three darker lines in the middle part. The second pair of wings are steely-grayish-brown. Eggs are oval greenish 1.8 to 2.2 mm long. A newly hatched caterpillar is about 4 mm long, yellow. Since the forth instar the caterpillar has round orange spots on both sides of the body except the second and third segment. The head capsule is about 5 mm radius and the body is about 70 mm long at the last larval instar. Pupae are dull brown 40 mm long and 9 to 12 mm wide. Biology: Swarming period is in June-July. Moths fly in late evening, some individuals also during the day time. They feed on a nectar of different flowers. After feeding moths mate on tree trunks and in crowns. Females lay eggs on needles and twigs individually or in groups. A fecundity is about 100 to 500 eggs. Caterpillars hatch about 14 days after eggs were laid. A duration of the first instar development is 3-4 days. The needles damaged by the first and second instar caterpillars have a saw shape. The second instar caterpillars develop 4-5 days, those of the third instar develops about 6 days. The fourth instar caterpillars molt after 8 day feeding, and the duration of the fifth instar development is 9 to 11 days. Old caterpillars (3rd through 5th instar) consume whole needles and increase their body size from 25 mm up to 70 mm. In October caterpillars descent to the forest litter and pupate in pupal chambers. A pupal stage can last from 8 months to 2 years. Damage: The pine hawk moth is often observed during the autumnal searches for the insect pests, however it does not cause any damage of economic importance. This species rather accompanies other pine defoliators. Preventive measures: Preventive measures are based on appropriate estimation of forest threat due to the pine hawk moth and other defoliators and protection of wild pigs, mice, bats, birds and other natural enemies. Forecasting: Forecasting is based on autumnal searches of pupae in forest litter. Control measures: Biological (based on bacterium Bacillus thuringiensis) and chemical (chitin synthesis inhibitors) may be used to control the pine hawk moth.
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Forest Pests: Insects, Diseases & Other Damage Agents |
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