Impact of a biological control agent, Chiasmia assimilis, on prickly acacia (Acacia nilotica ssp. indica) seedlings

► Chiasmia assimilis is an established biocontrol agent for prickly acacia in Australia. ► Its impact on potted seedlings was evaluated at a field site in northern Queensland. ► An insect exclusion trial was conducted to determine effects on seedling growth. ► Trial seedlings were grown in both full sunlight and beneath an existing canopy. ► Insect herbivory had significant negative effects on seedlings below the canopy only.