Hello, thought I’d write down a few tips for sketching trees. The biggest difficulty when sketching trees, either from photos and particularly when outdoors, is how to simplify without resorting to stereotype and your drawing becoming cartoon like. You definitely need to avoid attempting to draw every leaf and branch, yet you should aim to provide enough detail to show its shape and character. I chose to draw from a photo of an oak tree, which I have attached. I highly recommend doing this outdoors though, if you get a chance.
You will just need a pencil and paper. I used a 2B most of the time, then switched to a 6B for the later stages.