Soft scales (Coccidae)

Host plants: These insects are polyphagous, meaning they feed on a vast range of plant species. They are significant pests in both agricultural orchards and ornamental horticulture, commonly infesting citrus trees, grapevines, fruit trees, and various indoor plants like palms and ferns.

Biology and life cycle: Soft scales exhibit significant sexual dimorphism. Females remain sedentary after reaching maturity, protecting their eggs underneath their bodies. The only mobile stage is the first-instar nymph, known as a "crawler," which actively disperses to new growth sites on the host plant before settling down to feed.

Nature of damage: As sap-sucking insects, they pierce plant tissues to feed on phloem sap. This leads to yellowing, stunted growth, and canopy thinning. Additionally, they excrete honeydew, a sugary substance that facilitates the growth of sooty mold, which blocks sunlight and reduces the photosynthetic efficiency of the leaves.

Control measures: Management of soft scales is challenging due to their protective body covering. Recommended strategies include:

• Application of systemic insecticides that are taken up by the plant's vascular system.
• Use of horticultural oils to smother the nymphs and adult females.
• Pruning and destroying heavily infested branches to reduce population pressure.
• Monitoring for the presence of crawlers to time insecticide applications accurately.