Davis cicada

Systematic position: The Davis cicada (Tibicen davisi) is a member of the order Hemiptera and the family Cicadidae. As a significant species within this family, it is recognized for its unique life cycle and the audible signals produced by adult males during the mating season in various habitats.

Affected crops and damage: This pest primarily affects a wide range of woody ornamental and forest trees. The most significant damage occurs when nymphs feed on tree roots, which can stunt tree growth. Additionally, female cicadas cause physical injury to twigs by inserting their ovipositors to lay eggs, which often leads to the death of distal parts of the branches.

Biology and life cycle: The life cycle of Tibicen davisi is complex and long-term, characteristic of periodic and annual cicada groups. Nymphs remain underground for several years, feeding on xylem sap from tree roots. Once they reach maturity, they emerge from the soil to molt into adults, spend a short period mating, and then lay their eggs into the bark of host plants.

Economic significance: High populations of Davis cicada can result in substantial physiological stress to host trees, particularly in young saplings. By creating wounds on twigs, the insect provides entry points for various fungal and bacterial pathogens, which can exacerbate the damage and lead to crown dieback or increased susceptibility to drought and other environmental stressors.

Control measures: Managing Tibicen davisi requires a combination of vigilance and cultural controls:

• Regular monitoring of tree canopy for signs of oviposition scars.
• Pruning and destroying infested branches before egg hatch to reduce local populations.
• Application of appropriate insecticides during peak adult activity if damage thresholds are exceeded.
• Maintaining tree vigor through proper irrigation and fertilization to help plants withstand root feeding.