Flute
Is there a reason you're in the bamboo grove? Why yes there is. It's so you can get yourself some bamboo and make a flute out of it.
Imagine yourself cutting down some bamboo, thinking "this is the reason I'm here, I need a flute, asap!" There is no other reason to be here besides this.
てき
ふえ
None
You cut down the bamboo and whittle a flute. You start playing a song. You know the reason why. An alien spacecraft comes flying down and drops a box full of alien tech (てき) in front of you.
You've done what you came to do. You summoned an alien craft with your bamboo flute, gaining some alien tech in the process. Open up the box to see what tech awaits you.