Brown soft scale infestations generally develop during the summer and fall months. Early signs of infestation are easily overlooked during monitoring activities until blackening of leaves by sooty mold fungi becomes noticeable. Tree vigor is diminished by feeding activities and inhibition of photosynthesis by sooty mold growing on the leaves. Citrus mealybug is controlled most effectively with pesticides during early stages before protective wax secretions and sooty mold form. Monitoring activities must be concerned with identification and quantitative assessment of first and second stage larvae.
Mature mealybugs are highly resistant to contact pesticides.
Heavy infestations interfere with fruit development and may cause fruit drop. Sooty mold is difficult to remove at the packing shed, often resulting in downgrading of fruit. Mealybugs have several predatory and parasitic natural enemies. Severe outbreaks in orchards not normally affected by mealybugs usually are the result of pesticide-related reductions or other unfavorable circumstances affecting natural enemies. Texas leafcutting ants can cause serious damage to citrus, particularly in young plantings, so monitoring notes on location and severity of infestations will facilitate control efforts.