I have a avocado tree in the backyard. The leaves are getting a lot of brown dots. Is it getting infected?thanks a lot!!
Sarah, your avocado has injury from a pest called the "persea mite". If you do an image search on this term you will find a number of images that show the same kind of damage. This article by the California Avocado Growers contains some interesting details about treatment and also a list of other plants which can act as hosts to the same mite. If you have these plants locally then they can jump to your avocado when the time is right.
Your situation is pretty far advanced, so read this article from University of California which suggests an insecticidal oil application.