@Nevin Hersch they grew too much

I guess theres no difference between countries Powdery mildew (echter mehltau) is removable when you rub the leaf and powdery mildew needs a dry climate while downy mildow needs high humidity

@Nevin Hersch the rubbing test is an easy way to tell if its powdery mildew. With the downy mildew (I have to say it's easier in English to understand the difference) like the word downy can be used as a donkey ladder it contains the word "down" downy mildew appears on the down side of the leaf and powdery on the upper side Powdery is removable downy not

this was an Acer the problem was the huge wound right underneath the fork because that area is very important to hold the stems together as you can see from the too and the side I could stick about 50cm (20inches) into the wood. you can also see in picture number 3 the fiber compression from the weight of the stem picture one shows the forces in U and V forks as you can see the forces in V forks are working against each other so they basically push each other away thats the reason for the failure plus the fiber is not interlocked like in an U fork.

@Tim Shawley in 🇩🇪 Germany

species could be an Oak tree to me it looks like nothing is wrong with, despite from a small frame like this you cant tell if something is wrong it not I guess its about these lighter spots which should be harmless moss or idk if thats the right word- fles

@Tim Shawley thanks! yeah I had a second look and saw that the spots look different on the surface compared to the bark round them. They almost look like callus yes, you could be right that its a mechanical damage.