I have one in my backyard. I believe it's a tilia cordata or the little leaf kind. It's about 14 years old and is about 35 feet tall. The previous owners planted it too close to the fence. It looks like it got overwatered and tried to pull itself out of the dirt. The roots are terrible. They are pulling up the fence. We recently redid the sod and irrigation in our backyard. The roots from that tree spread about 30+ feet out from the base and were killing the grass. It's a beautiful tree but not something to plant on a small plot in the city. When the fence gets a little worse, it will have to be taken out along with the fence because it's on both mine and the neighbor's property now. It does produce a lot of shade and would be beautiful in a yard with grass that doesn't need much sunlight.

Most of the images show water shortage. Not disease. Perhaps occurred suddenly, as in windy; extreme high temps that burst in on a hot spell; very low humidity; too small a pot (are they in pots?)

WJ You are correct, it is not a disease. I do not think leaves will revert to 'perfect' state; there are usually little pimple-like bumps left on leaves. If the oedema blisters are large & they ruptured, they will scab over, so there will be a scabby brownish spot on the leaf. Good ventilation helps, as would lower humidity - using small fan may help. After watering, pot should not sit in a saucer with water. I do not use peat/coco peat in gritty mix. I do not use any charcoal so not sure what it will do. The mix you describe sounds quite good to me. I have semps overwintering outside, and they get covered by snow. So there is lots of moisture, but they are in very gritty mix. During summer, I do not water them, they get water when it rains. I don't remember having any oedema on semps, but I see some on few leaves of jades that were outside spring to fall. We have some humid days during summer, most likely not as high as in your location. We get reasonable rains, but it doesn't last for many days in a row. Btw, do you know what is used as a root rot preventative in the mix?

Thanks Helen. I checked it and found out another post by someone. After reading it, I think I'd be good to go in the Spring to behead her! Her, the plant. :P https://getbusygardening.com/aloe-vera-plant-care/ The section under Propagating Aloe Vera Plants says, "If your aloe vera plant has grown huge and has a long stem at the bottom (and you’re feeling brave), you could try propagating the whole thing from one large stem cutting (this is how I ended up with two humongous aloe vera plants!)." Nik, the big one was repotted to a larger pot about a year and a half ago. I had kept half of the dirt in and added new dirt. I didn't want to startle it, but maybe I'm completely wrong. Maybe I'll give it 100% new dirt soon, but then again it's winter here. We actually just had our first snowfall today, and a lot of snow. Wasn't sticking though! I wish the leaves got fat! I give it a little bit of this for food and hasn't died yet! https://www.amazon.com/gp/product/B01JIRKYJ2/ref=oh_aui_search_detailpage?ie=UTF8&psc=1 Great information to help me open my eyes more! I do have two LED grow lights w/ full spectrum.... Thoughts?