Trigona

Trigona is a genus of highly social insects belonging to the order Hymenoptera and the family Apidae. Known as stingless bees, they are widely distributed across tropical and subtropical regions worldwide.

These insects are significantly smaller than common honey bees. Their bodies are typically dark, almost black, with a characteristic sheen and sometimes exhibit yellowish markings on the head or thorax.

A distinctive feature of Trigona bees is the absence of a functional sting. However, they possess highly developed, powerful mandibles which they use both for defense of the nest and for gathering building materials.

Their biology involves establishing perennial colonies inside tree hollows, rock crevices, or specialized structures built from a mixture of resins, waxes, and plant fibers.

The life cycle follows standard holometabolous development: egg, larva, pupa, and adult. The colony maintains a strict social hierarchy that dictates the labor and role of every individual member.

While often regarded as beneficial pollinators, in certain agroecosystems Trigona bees can act as pests, causing physical damage to young saplings and high-value fruit crops.

The primary damage occurs due to the bees' habit of harvesting resins, bark, and plant sap to construct their nests, which stresses the plant tissues and reduces vigor.

Young fruit saplings are particularly vulnerable, as these bees may gnaw on tender bark, causing the shoots to wither and significantly stunting the tree's growth.

Furthermore, the damage to the bark creates entry points for various fungal and bacterial infections, which can lead to tree decline or mortality due to developing necrosis.

In some regions, the bees have been observed damaging the skin of tropical fruits while attempting to access sap, which lowers the commercial quality and appearance of the produce.

The main sign of Trigona presence is the occurrence of characteristic jagged marks or shallow excavations on the bark of young branches, resulting from their feeding and harvesting activities.

The presence of the insects themselves is an obvious indicator: they are often seen flying actively around trees, particularly during the warmest hours, and congregating on fresh wounds or damaged wood.

Near potential nesting sites in the orchard, one might find accumulations of distinct building material, resembling a hardened mixture of dark resin and fine wood shavings.

During routine inspections, one may notice gradual wilting of individual branches or terminals that have been intensively targeted by the bees' mandibles during the growing season.

Another indirect sign is the delayed healing of wounds on tree trunks, as the bees tend to revisit favorite sites periodically to collect sap and resinous exudates.

A highly effective method of protection is sealing damaged bark areas with horticultural grafting wax or specialized protective pastes, which prevents the bees from accessing the exposed wood.

Sanitary pruning is strongly recommended to remove potential nesting sites, such as old hollows or dead, decaying branches that naturally attract Trigona colonies.

Applying repellent substances to the bark of young trees can help deter the insects and prevent widespread damage during the most critical periods of the tree's development.

In commercial orchards, utilizing protective mesh or physical barriers on trunks is an effective strategy that prevents the bees' mandibles from contacting the tender bark tissues.

• Regular monitoring of bark condition across the orchard.
• Removal of old hollow stumps from the garden area.
• Application of biocontrol agents to protect bark wounds from pathogens.