njemački

Gradationen des Schwammspinners in Kroatien von 1970 bis 2000

Gypsy Moth &#8211 ; ; Lymantria dispar L. (Lepidoptera) represents one of the most significant pests on oak in Croatia. As a defoliator it was known as early as in 18th century, when the first total defoliations on larger areas were recorded. The most severe gradations of Gypsy Moth in the last century occurred in the 1945-1950 period. During the last 30 years Gypsy Moth has been intensively monitored and the data have been sent to the Diagnostic-Prognostic Centre in Jastrebarsko. Five different classes of attack are differentiated: 1%>-Class 1 ; 1-5%-Class 2 ; 5-20%-Class 3 ; 20-50%-Class 4 and > 50%- Class 5. Culminative gradations showed decline in 1973, 1983, 1988 and 1992. Method of moving average shows that the trend for Class 1 and Class 2 is positive, but negative for Classes 3, 4 and 5. Spectral analysis has confirmed that weak attacks occur every 8 years, while more severe attacks every 10 years. Operational data indicate that the intensification of attacks can be expected in coming years.

Lymantria dispar; Gradation; Eiche

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