2 people thought they were yellow box. I have added images of the trees and the bark. Hopefully you can make a positive identification without the flowers. We do have Blakely's red gum in HGW.
According to David Hollis's book 'Australian Psylloidea' (ABRS, 2004), 8 spp of psyllids including Cardiaspina tenuitela and Lasiopsylla rorundipennis are recorded from Euc melliodora. I think these look more like the Lasiopsylla.
Lasiopsylla lerps are dense and woolly looking. In fact infested host trees look dripping like snow. There are some pictures in my leaflets on insect pests of farm trees produced many years ago. I don't have access them at the moment as I am in the Daintree. I still think the lerps pictured are white lace lerps in the genus Cardiaspina. If they are on E . melliodora then they are C tenuitela, as suggested, that is also pictured in the leaflets. As the pictures show, the lerps are more rectangular (tenuitella) than oval (albitextura). Close-ups of lerps are always helpful for identification.
Keep arguing - all young growth ( young trees and suckers from the base of fire burnt trees) are severely affected to the extent that HGW members have become worried about it. We have a program to remove the suckers (not because of the lerp) and young trees will outgrow the problem. Maybe I should take more photos.