Zimmermann, H.G., & Moran, V.C. 1991 Biological control of prickly pear, Opuntia ficus-indica (Cactaceae), in South Africa.. Agriculture, Ecosystems & Environment 37(1/3): 29-35.

Notes: [In the special issue: Biological control of weeds in South Africa / edited by J.R. Hoffmann.] This report reevaluates the ability and desirability of Dactylopius opuntiae and Cactoblastis cactorum to control O. ficus-indica. In cooler, higher rainfall areas D. opuntiae is relatively ineffective. Perceptions have changed over the years from regarding O. ficus-indica as a pest to regarding it as a host for commercial production of dye stuff from the cochineal Dactylopius coccus.