posted 7 years ago
I'm not exactly sure what happened in the first picture but since all leaves are dead on an entire branch with the rest of the tree appearing alright, it leads me to believe perhaps a canker or a pest like a borer and it's grubs have girdled the cambium layer under the bark which is where the sap and water flow, hence all the dead leaves. Prune off that entire branch. The second picture appears to be a disease and could be a myriad of possible infections. My guess is a bacterial or fungal leaf spot disease such as, but not limited to, apple scab, rusts, anthracnose, downy mildew, early blight, etc. One method to deal with bacterial and fungal infections is with microbes. I myself mix Effective Microorganisms, a product called Serenade, and molasses with a little non-chemical dish soap as an emulsifier/surfactant to make a foliar spray to manage such diseases on my fruit trees. This technique requires regular reapplying throughout the growing season.
"Study books and observe nature; if they do not agree, throw away the books." ~ William A. Albrecht