Set Up, Care
A tree is what a lifeguard uses to set up the station where he'll care for the people on the beach and in the water. Trees provide the shade lifeguards need to take care of half-drowned kids and grannies with sand stuck in their bathing suits. That's why they set up their care stations here.
Watch the lifeguard walk around the beach. He needs to pick a nice big tree for his set up, so he can provide the best care possible.
こう
かま
None
You look closer at the set up and realize the lifeguard is こういち! You know he teaches Japanese but... is こういち really qualified to care for people like this?
Imagine こういち setting up a care station. You hope you don't get in trouble in the water so you don't have to see how good he is at caring for people. Hint: when you see the "lifeguard" radical, the reading is probably going to be こう.