Neodiprion sertifer: Schadauftreten in Kärntner Weißkiefernbeständen

Neodiprion sertifer: Pine sawfly gradation in Carinthia (Austria)

Wien

1998

4 Lit. Ang.

Unselbständiges Werk

12531

200104807

Since 1995 the Fox-coloured sawfly (Neodiprion sertifer) has caused severe damage on 60-100 year old Scots pine in the forest districts of Klagenfurt and Völkermarkt. About 5500 ha of secondary pine stands at altitudes between 400 and 600 m have been infested (340 ha of them heavily). The same stands had already been damaged in 1961-65 by this sawfly. Different investigations concerning critical numbers of healthy cocoons and egg masses, the rate of parasitism and assessment of crown defoliation have been carried out in 1997. The numbers of healthy cocoons varied between 0 and 112 per square meter, the number of egg masses per tree between 6 and 44 after 30 minutes of searching time (4 persons).