Rusty red, worm-like discharge from apple tree trunks?

Hello everyone 🙂 Can anyone tell me what's wrong with my little apple tree? See picture. The rust-red discharge is crumbly and can be removed in one go. But the resin would be honey-like, right? I haven't noticed any pests, apart from a few ants. The discharge is "growing back," though, and the tree has…

Does a fruit plant have to be grafted and what is the purpose of grafting?

Hello, I used to take an advanced biology course (including a semester of genetics). Even after reading the Wikipedia article on plant breeding, I still don't understand the biological connection. When I was a child, I was always told that a tree (e.g. an apple tree) had to be grafted so that it would later…

How can you combat powdery mildew on apple trees?

Hello, my apple tree has powdery mildew. I bought a spray for fruit trees from Raiffeisen, but unfortunately, it didn't help much. Now I've used baking soda, but I don't know how often I need to repeat it. There are conflicting instructions online. Does anyone have any experience? One says daily, another says weekly… I…