Yeah, your triple digit streak is making news across the nation. Lucky, lucky you. ;) It probably doesn't do them any good, but it's also possible it's Powdery Mildew. I know, sounds dumb, but it's really a soil-born fungus that spreads by air. Do a little googling on it, and see if you can find pictures to see if it looks familiar to you. I know cukes, squash, and lilac are particularly suseptible. If that's it, at least you don't have to treat the leaves in the middle of the day. In the evening, which really isn't any better than the middle of the day, but at least you're out of straight down sun. And, since you're also in the middle of a mean drought, you won't have to repeat as often as usual. ("Repeat treatment every three weeoks or whenever it rains.") And, yes. If you're beginning to wonder, there will be a day when Dallas goes back to cooler weather. Promise. I can't make the same guarantee about your drought, but I'm pretty sure that will end too, eventually.

You've got to kind of wonder about the training of a 'master gardener' who believes fungal problems are only directly related to rain and lack of summer heat.......There are many causes to fungal issues and heat and dryness can certainly be contributing factors, just as much as damp, rainy weather. Heat and dry conditions are primary contributors to the development of powdery mildew, for example. It is impossible to be certain without an accurate diagnosis, but the symptoms resemble those of verticillium wilt, which is a soil borne fungal pathogen (no water or mild temperatures required - it just exists). It typically will affect only selected portions of the tree, leaving the rest looking fine. Until it fails completely :-(( Take a sample of the affected branches in to your local Cooperative extension office for diagnosis and ID. If it is VW, there's not much you can do other than remove the tree.

Looks like environmental stress. Ran short of water a while ago. As far as I can tell, only a few bottom leaves are affected whereas the other growth looks excellent. Keep the lower leaves as long as they have some green color as they are contributing to the plant.'s general health.

"dryed shrivelled green leaves" is usually either a nutrient issue or a pest issue. Any sign of pests? Look for spider mite webs or aphids. What and how much have you fed it? Is it in a container? If so are you sure it isn't root bound? Need more info please. Dave