Lula avocado leaves browning and dropping off (insect pest?)
My lula avocado leaves get brown blotches, then drop off. Underneath the leaves, I can never see live insects, but always find little black dots. MANY of the leaves on the tree look like this. The black dots are not part of the leaf, they are just stuck to it, similar to insect eggs or husks or something like that.
See the picture to see both a browning leaf and the black dots.
Is this an insect causing this? The tree has lost half of its leaves this summer due to this.