Tubulorum oyster scale

Lepidosaphes tubulorum, commonly known as the tubulorum oyster scale, is a damaging insect pest belonging to the family Diaspididae, order Hemiptera. It is recognized as a significant threat to various deciduous trees and shrubs, feeding exclusively on plant sap through its specialized piercing-sucking mouthparts.

The scale insect primarily targets fruit trees, including species of the Prunus genus, as well as apple and pear trees. Infestations are characterized by dense colonies covering the branches and trunk, which sap the vitality of the host tree, leading to stunted growth, reduced leaf density, and in severe cases, the death of individual branches.

The life cycle of this species consists of a single generation per year. Mated females overwinter under their protective waxy shields on the bark. As spring temperatures rise, the females lay eggs beneath the shield. Once hatched, the mobile nymphs, known as crawlers, move across the bark to find suitable feeding sites where they settle and develop their own protective shells.

The damage caused by these insects is both direct and indirect. By removing large quantities of plant fluids, they disrupt the tree's vascular system. Furthermore, the presence of these scales can cause localized tissue necrosis, bark cracking, and weakening of the plant's natural defenses, making it more susceptible to environmental stressors and pathogens.

Integrated Pest Management (IPM) is essential for controlling this scale. Practical measures include pruning and removing heavily infested branches, as well as applying horticultural oils during the dormant season to suffocate overwintering females. During the crawler stage, contact or systemic insecticides can be applied to effectively break the infestation cycle.

• Regular inspection of bark for scale presence.
• Pruning and disposal of heavily infested plant material.
• Dormant season application of horticultural oils.
• Targeted insecticide treatments during the crawler emergence period.