Zeuzera multistrigata, Moore, 1881

Chi, Nguyen M., Bao, Hoang Q., Pham, Duy L., Loi, Vu V. & Yakovlev, Roman V., 2022, The stem borer Zeuzera multistrigata Moore (Lepidoptera, Cossidae): a serious pest undermining Eucalyptus plantations in Northern Vietnam, Ecologica Montenegrina 60, pp. 4-12 : 7-8

Zeuzera multistrigata damage in Eucalyptus hybrid

Affected Eucalyptus stands were observed in plantations containing trees 16 months of age. In general, all Eucalyptus stands damaged by Z. multistrigata , trees were found to be declined and broken. Boring holes were clycle with inner dimeter of 0.6‒1.0 cm ( Fig. 3a ), situated at 0.5‒4.5 m above the ground. The tunnels were circular, 0.8‒0.9 cm in diameter, 20‒40 cm in length ( Fig. 3b ), and they run throughout the wood portion. Before pupation, the larvae often excavated horizontally long tunnels around the trunk of the tree, and consequently the damaged trees were easily broken during the strong winds ( Fig. 3c ).

The infestation level (P%) and the average damage index of Z. multistrigata in Eucalyptus hybrid plantations at the age of 12−52 months are shown in Table 2. In both Lao Cai and Phu Tho provinces, the damage varied significantly among the tree ages (P <0.001). The damage were highest in the plantations of 16-month-old and none of damage was observed in 52-month-old plantation. The damage in the plantations at the age of 12‒40 months in the Phu Tho was higher than those in the Lao Cai.

Figures

Fig. 3 Symptoms of Zeuzera multistrigata in Eucalyptus hybrid: a. damaged tree; b. damage to the wood; c. broken tree after sereous damaged by Z. multistrigata.