Examine stems

The bark on the trunk appears normal, although it shows cracks at the base of the tree. You squat down for a closer look and notice that the bark is peeling away and appears discoloured. There are no signs of mushroom-type fruiting bodies around the trunk. Neither are there signs of mycelial fans or rhizomorphs under the small piece of bark you managed to pull away.

Squatting down, you take out your pocketknife and cut into the bark at the base of an affected tree. The bark and phloem is seen to be dark brown and it has a sour smell. Further cutting reveals this area of discolouration extends up and around the trunk, and down along the main roots. The lesion has a zonate margin. Nasty...!