Chalcophorella buprestid

The Chalcophorella buprestid (Chalcophorella stigmatica) belongs to the Buprestidae family, commonly known as jewel beetles, within the order Coleoptera. Adult beetles are relatively large, typically measuring 25–30 mm in length, and possess an elongated, slightly flattened body shape with a distinct metallic sheen.

Their coloration ranges from bronze-green to almost black, a feature that provides excellent camouflage against tree bark. The pronotum and elytra are covered with fine punctures and a pattern of small, light-colored spots, making them difficult to detect when resting on trunks.

Larvae are legless, flattened at the thoracic region, and creamy-white in color. They spend their entire developmental period hidden beneath the bark or within the wood, which complicates early detection and management efforts.

These insects favor warm, sunny locations and are frequently found on trees in open areas, south-facing slopes, or sparse plantations where the trees receive maximum sun exposure.

Adults are diurnal and most active during hot, sunny weather, often seen on the surface of branches or trunks engaging in mating behavior or feeding on foliage.

The primary hosts for this pest include broad-leaved trees, particularly those in the Rosaceae family. In fruit orchards, the most susceptible crops include cherry, sweet cherry, apricot, peach, and almond trees.

In addition to orchard crops, the Chalcophorella buprestid can infest various forest and ornamental trees, including poplars, willows, and elms, especially if the trees are already suffering from physiological stress or neglect.

The larvae cause the most significant damage by boring winding galleries under the bark, which they pack tightly with frass. This activity disrupts the transport of water and nutrients, leading to the dieback of individual branches or the entire tree.

Infested trees show reduced vigor, decreased yield, and increased susceptibility to secondary infections and other opportunistic pests that exploit the weakened tree’s defenses.

While adult beetles feed on young leaves and succulent shoots, this damage is generally minor compared to the structural destruction caused by the larval stage feeding deep within the cambium.

The emergence of adult beetles typically occurs in late spring or early summer, generally between May and June, continuing through July depending on the local climate and seasonal temperatures.

Females deposit eggs in the cracks and crevices of the bark or into mechanical wounds on the trunk and large skeletal branches, carefully selecting sites suitable for larval penetration.

The larval stage is lengthy, often requiring one to two years to complete. Throughout this period, the larva feeds continuously, excavating deeper into the wood to prepare for the final stages of its development.

Pupation takes place within the wood, where the larva constructs a specific chamber known as a pupal cell. Most populations overwinter as larvae or fully formed beetles inside these protected chambers.

Once metamorphosis is complete, the young adult beetles bore characteristic oval-shaped exit holes through the bark to emerge and begin the cycle again.

The most prominent sign of an infestation is the presence of distinct oval-shaped exit holes on the bark, left behind by the adults after they emerge from the tree.

Near the trunk base or at sites of entry, one may notice accumulations of frass, a mixture of fine sawdust and excrement that the larvae push out from their galleries to clear space.

Infested trees may exhibit gumming (gummosis), especially in stone fruits, alongside cracked and peeling bark, indicating that the tree is attempting to respond to the internal damage.

By carefully removing the bark in heavily infested areas, one can uncover the wide, meandering galleries, which are usually tightly packed with sawdust and waste matter.

The canopy of an infested tree typically shows signs of decline, including premature yellowing of leaves, dieback of the upper crown, and the eventual death of branches as the infestation progresses.

The most effective management strategy is maintaining high tree vigor through proper irrigation, balanced fertilization, and correct pruning techniques, as healthy trees are less attractive to these beetles.

Timely removal and destruction of dead or heavily infested branches are crucial, as these materials serve as reservoirs for future generations of the pest.

Protecting tree trunks from sunburn and physical damage, for instance through lime washing, makes the bark less hospitable for females looking to deposit eggs during the spring.

In cases of severe infestation, insecticide treatments applied during the period of peak adult emergence can help reduce beetle populations before they can successfully reproduce.

For localized infestations on valuable trees, mechanical cleaning of the damaged bark followed by the application of disinfectants and wound sealants can help the tree recover.