The controls are included in the description section, and a hint is given that you will need to shake trees. I just played this for the first time and had no issues. Great game, love the art <3
If it's not included in the game itself it's a poor design decision. A game should teach the player all the mechanics within the game itself.
Skill issue
Part of the fun of this, and MANY other games, is to EXPLORE. If you get told what to do all the time then there wouldn't be a game to play.