Why so sadist ? I thought you learned from HW :(

[Pulsahr]

Do you mean pine logs at the heron's flight? Isn't there some set of stairs that allow you to get up there?

There is. And you can't use them.
To verify : Go there, make sure your mount is configured to enter fly mode with double jump, and try to reach the upper part without flying.
Unless I'm stupid, you just can't, there is a missing step.