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It has also been demonstrated that ants compete with parasitoids, including Aphytis spp., for honeydew as a source of carbohydrates produced by non- Aphytis hosts (Calabuig et al., 2015; Tena et al., 2013) and also prey on Aphytis wasps (Heimpel et al., 1997). The constant disruption and interference of host examination and oviposition lead to dramatically reduced efficacy in host parasitism (Rosen & DeBach, 1979; Martinez-Ferrer et al. , 2003). decreased by 94% when the attendant ants ( Lasius niger Linnae - US) were excluded. Moreno et al. (1987) found that in the absence of ants, populations of honeydew-producing citrus mealybug ( Planococcus citri Risso), woolly whitefly ( Aleurothrixus floccosus Maskell) and non-honeydew-producing red scale were effectively reduced by their respective natural enemies. Valencia trees treated with special ant- limiting bands had significantly lower ant (P. megacephala) and red scale infestations than untreated trees (Steyn, 1954a). Similar observations were made by Itioka and Inoue (1996), where the infestation by mealybug ( Pseudococcus citriculus green) in a satsuma orchard Even in the absence of honeydew- producing scale, the reduction of parasitism of armoured scale by Aphytis spp. due to ant disturbance can be significant, and the effect of ants on Aphytis is rated next to weather extremes and detrimental pesticides (Heimpel e t al., 1997; DeBach, Fleschner, et al., 1951; Consequently, control of ants is recommended in order to facilitate the biological control of red scale (Rosen & DeBach, 1979; DeBach, Dietrick et al., 1951; Buckley, 1987; Bartlett, 1961). Antlions (family Myrmeleontidae ) trap ants on orchard floors and are an effective natural enemy of ants when present. does disrupt the parasitoids and predators of red scale, and it has been established that certain ant species cause coincident infestations of red scale, among other non-honeydew producing insect pests (Rosen & DeBach, 1979; DeBach et al., 1951; Steyn, 1954b; Compere, 1961; Annecke, 1958; Bedford, 1968; Steyn, 1954a; Pekas et al., 2011; Samways et al., 1982; Samways, 1983; Samways et al., 1998; Flanders, 1945). Figure 1: Pugnacious ants tending to a citrus mealybug . Figure 2: Pugnacious ants tending to soft brown scales on a new growth flush. For a full list of references and more information, email ernst@laeveld.co.za. Dr. Ernst de Beer business manager, Laeveld Agrochem Ernst de Beer Business Manager, Laeveld Agrochem LAEVELD AGROCHEM 37 Observations record that ants assist with the transport of insects and parental care of some hemipteran species to enhance brood produc- tion, so confirming their mutualistic, symbiotic rel tionship. Red sc le does not p oduce honey and it is not, therefore, directly attended by ants. Howev r, increased ant activit disrupts the parasitoids and predators of red scale, and it has been established th t c rt in ant species c use coincident infestations of red scale, among oth r non-honeydew producing insect pests (Rosen & DeBach, 1979; DeBach et al., 1951; Steyn, 1954b; Compere, 1961; Annecke, 1958; Bedford, 1968; Steyn, 1954a; Pekas et al., 2011; Samway et al., 1982; Samways, 1983; Samways et al., 1998; Flanders, 1945). It has also b en demonstrated that ants com- pete with para itoids, including Aphytis spp. , f r honey ew as a source of ca bohydrates produced by non- Aphytis hosts (Calabuig et al., 2015; Tena et al., 2013) an also pre on Aphytis wasps (Heimpel et al., 1997). The constant dis- ruption and interference of host examination and oviposition lead to dramatically reduced efficacy in host parasitism ( Rosen & D Bach, 1979; Martinez-Ferr r et al., 2003) . Val ncia trees treated with special ant-limiting b ds had significantly lower ant ( P. m gaceph- ala) and ed cale infestation than u treated trees (St n, 1954a). Sim lar observ tions were mad by I oka and Inoue (1996), where the infestation by mealybug (Pseudococcus citriculus Green) in a Satsuma orchard decreased by 94% when the attendant ants (Lasius niger Linnae- us) were exclud d. Moreno et al. (1987) found th t in the absence of ants, populations of honeydew-producing ci ru mealybug (Plano- coccus c tri Risso), woolly white y ( Aleurothrixus flocc sus Maskell) and no -honeydew-produc- ing red c le were eff ctive y r du ed by their r spective natural enemies. Even in the absence of honeydew-producing scale, the reduction of parasitism of armoured scale by Aphytis spp. ue t ant disturbance can be significant, and the effect of ants on Aphytis is rated next to w ather extremes and detri- mental pesticides (Heimpel et al., 1997; DeBach, Fleschner, et al., 1951; Rosen & DeBach, 1979). Consequently, control of ants is recommended in o der to facilitate the biological co rol of red scale (Rosen & DeBach, 1979; DeBach, Dietrick, et al., 1951; Buckley, 1987; Bartlett, 1961). Antlions (family Myrmeleontidae) trap ants on orchard floors and are an effective natural enemy of ants when present. S i n c e 1 9 9 1 5. Buckley, R.C. 1987. Interactions involving plants, Homoptera and ants. Annual Review of Ecology and Systematics. , (18): 111–135. 6. Calabuig, A., Tena, A., Wäckers, F.L., Fernández-Arrojo, L., Plou, F.J., Garcia-Marí, F. & Pekas, A. 2015. Ants impact the energy reserves of natural enemies through the shared honeydew exploitation. Ecological Entomology, 40(6): 687–695. 7. Compere, H. 1961. The red scale and its insect enemies. Hilgardia, 31(7): 173–278. 8. DeBach, P., Dietrick, E.J. & Fleschner, C.A. 1951. Ants and citrus pests. Calif. Agric., 5(7): 7,14. 9. DeBach, P., Fleschner, C.A. & Dietrick, E.J. 1951. A biological check method for evaluating the effectiveness of entomophagous insects. Journal of Econ mic Entomology , 44(5): 763–766. Pugnacio s nts tending to a citrus mealybug.