French's canegrub

Lepidiota frenchi

Overview:

Lepidiota frenchi, commonly known as the French's Chafer Beetle, is a beetle species that can become a significant pest in turfgrass and agricultural fields. Native to Australia, it has spread to other regions, causing damage to grasses and crops.

Detailed Appearance:

  • Adult French's Chafer Beetles are medium-sized, measuring about 1.5 to 2 cm (0.6 to 0.8 inches) in length.
  • They have a reddish-brown to dark brown coloration with a robust and oval-shaped body.
  • Antennae are clubbed at the tips, and the elytra (wing covers) may have distinct ridges.

Life Cycle:

  • The life cycle includes egg, larva (grub), pupa, and adult stages.
  • Eggs are laid in the soil, and larvae feed on plant roots, particularly grass roots.
  • Larvae go through several instars, pupate in the soil, and emerge as adult beetles.
  • The life cycle can span several months, with adults typically emerging in late spring or early summer.

Identification of Crop Infection:

  • Irregular patches of dead or yellowing grass in lawns or fields.
  • Presence of adult beetles feeding on leaves, causing characteristic notching along the edges.
  • Identification of C-shaped, white to creamy-colored grubs in the soil during larval stage.

Management Strategies:

  • Cultural Controls:

    • Implement proper lawn care practices, including regular watering and fertilization to promote healthy grass growth.
    • Avoid overwatering, as excessively moist soil can attract egg-laying females.

  • Biological Controls:

    • Introduce natural predators, such as parasitic nematodes, which can help control the larval population.
    • Encourage the presence of birds, as they feed on adult beetles.

  • Chemical Controls:

    • Use insecticides labeled for chafer beetle control, applying them during the larval stage.
    • Follow recommended application rates and safety guidelines.

  • Nematode Applications:

    • Apply beneficial nematodes to the soil, targeting the larval stage of the French's Chafer Beetle.
    • Ensure proper soil moisture for nematode effectiveness.

By combining these management strategies, it is possible to mitigate the impact of French's Chafer Beetle on turfgrass and agricultural fields. Early detection, proper lawn maintenance, and targeted interventions are key to effective pest control.