Chemical Control of Dreyfusia nordmannianae

1991

4 Abb., 5 Tab.

Unselbständiges Werk

8340

200078984

Various treatments against the chermes Dreyfusia nordmannianae have been compared in a silver fir plantation seriously affected after removal of the sheltering stand (in the Haute-Saone, Eastern France). Pyrethrinoids proved efficient, Deltamethrine more particularly: in the plots treated with this product (two automn treatments a year apart), the percentage of healthy saplings rose from 40 to 80%, while dropping to 20% in the control plots. On the other hand, systemic pesticides (organophosphates) showed quite inefficient.