Life cycles and shoot-feeding of the pine shoot beetles

The life cycle and shoot-feeding of Tomicus piniperda (L.) and T. minor (Hart.) (Col., Scolytidae) was studied in Simonstorp in southern Sweden (N. 58o 47', E. 16o 10') during the period 1972- 1976. Special attention was given to the seasonal feeding activity in the shoots of Scots pine (Pinus sylvestris L.). This shoot-feeding was related to certain events in life cycle: flight period, departure of parent beetles from brood logs, length of oviposition period and emergence of the new generation. The spatial distribution of beetles within the pine crown was also studied. The influence of environmental conditions and some population factors upon the shoot-feeding was discussed