Tea scale

The tea scale (Fiorinia theae) is a destructive member of the Diaspididae family within the order Hemiptera. It is recognized as one of the most serious pests affecting ornamental shrubs, particularly those in the Theaceae family, often causing severe damage in landscapes and nurseries.

This scale insect primarily infests camellias, tea plants, and hollies. It tends to cluster on the abaxial (underside) surface of the leaves, where the insects remain sessile for most of their lives, protected by their distinct, hard, waxy covers or tests.

The biological cycle is continuous in favorable climates. Adult females lay eggs beneath their armor, which protects the progeny from environmental stressors and pesticides. After hatching, the tiny crawlers emerge, seek out new feeding sites on the leaf surfaces, and settle to begin their development into adults.

Damage occurs due to the extraction of cell sap, which causes the foliage to lose vitality. Symptoms include chlorotic spots on the upper leaf surface, premature leaf drop, and overall plant decline.

• Yellowish or silvery spots on the leaf upper surface.
• Heavy infestation leading to leaf yellowing and shedding.
• Development of sooty mold caused by the sticky honeydew.

Pest management relies on integrated control measures. Pruning heavily infested parts of the plant and applying horticultural oils or systemic insecticides are standard practices. Timing the application to coincide with the crawler stage is crucial for maximum efficacy in controlling the pest population.