Hi, I have a approximately 3+ years old avocado tree. It is about 4 foot tall. It has been growing well until about 8-10 months ago, something has eaten off most of the young leaves on the top side of the tree. The leaves on the low part of the tree were virtually untouched. Then, I waited for the leaves to re-grow again. Once the Spring clicked in, the leaves growth nicely. Unfortunately, last Saturday's morning, I found out that all the new grow leaves were eaten off again. I couldn't find any worm or insect. The tree did not show any sign of problem with the leaves. Does anyone know why?
Did u check on the lower leaves? Could it be Leaf roller worm and Amorbia moth? "Leaf roller worm and Amorbia moth (called "gusano descarnador" in spanish) Amorbia emigratella Busck, A. cuneana Walsingham, A. essigana Busck (Lepidoptera:Tortricidae). The various species of Amorbia can be found in California, Mexico, and Central American countries such as Guatemala, Costa Rica and Panama. It is an endemic pest, present in the summer months. The adults are small moths from 2.5 to 3.0 cm in length and reddish-brown in color. The males are slightly smaller, with dark triangular spots in the center of the front wings, and dark distal edges. They are nocturnal in habits and have a life span of 15 to 20 days. The females lay eggs on the surface of leaves: masses of light green eggs in overlapping layers that require 13-15 days to hatch. The larvae go through 5 to 7 instars, which are differentiated by their color and size. In the first instars, they are yellowish-green in color, from 2 to 3 mm, and in the last they are dark green, from 20 to 30 mm. When they are bothered, they let themselves fall down suspended by a silky thread, which they use to roll up the leaves or fruits, and sometimes 2 or 3 larvae can be found together. The pupae measure an average of 18 mm and are green at first, later turning brown, and last for an average of 17 days. The complete life cycle varies from 98 and 120 days depending on the location and season of the year. This insect produces 2 or 3 generations per year, however, only one generation is enough to produce important damage. The damage is caused by the larvae, when destroying a large amount of foliage and tender shoots. " More on Avocado Production Guide
