Zeuzera pyrina (wood leopard moth)

Dead shoot tips appear and leaves on the apical portions of branches discolour prematurely. Infested branches break upon bending, due to the galleries made by caterpillars. Young caterpillars first enter shoots near the tip, and move onto older wood further down the branch when the shoot dies. Entry holes can be recognized by the frass, which resembles pellets of sawdust, and accumulates outside the entry hole for 6-9 months. Sufficient frass may fall on the ground to be a conspicuous symptom of infestation (Gatwick, 1992).

Z. pyrina is one of the most important pests of apple and pear orchards in Mediterranean regions. It can also be a serious pest of olive. On young trees, one caterpillar is enough to kill a tree, whereas 3-year-old trees can become extremely vulnerable to wind damage due to damage of the central axis. Older trees can be severely damaged, particularly in dry years and on dry ground. In the UK, damage caused by Z. pyrina tends to be more severe following hot, dry summers (Gatwick, 1992). Trees weakened by leopard moth attacks are more susceptible to damage from other xylophagous pests, such as the goat moth (Cossus cossus), hornet clearwing moth (Synanthedon myopaeformis) and bark beetles. The woolly aphid (Eriosoma lanigerum) can use old larval galleries of Z. pyrina as a refuge, enabling them to evade chemical treatments.