How do you nock Pokemon out of trees?

Answer 1

To knock Pokemon out of trees in Generation 2 games, you need to have the Headbutt TM, which can be found by a man in Azalea Forest. You then teach it to a Pokemon and head up to a small tree that can't be cut, but is smaller than other trees. Then press A, and it will ask if you want to Headbutt the tree. Say yes, and one of two things will happen:

1. Nothing happens

2. A sleeping Pokemon falls out of the tree (It will most likely be a Hoothoot) and you will battle it. It will start the battle asleep, so you have the edge.

Hope this helps.