Jahn, S., & Polesny, F. 1999 Population dynamics of San José scale and San José scale parasitoids in three different sites in Austria.. IOBC/WPRS Bulletin 22(7): 201-202.

Notes: Population dynamics of Quadraspidiotus perniciosus, Prospaltella perniciosi and Aphytis sp. was examined on unsprayed apple trees in three different locations of eastern Austria. The endoparasitic wasp Prospaltella perniciosi was naturalised in Austrian orchards in the sixties and seventies and has proved to be very effective. The genus Aphytis is native in Austria, but its parasitization rates are described as insignificant in literature.