Final answer:
In the book "Hatchet", a boy climbs a tree to try and hide from a threatening moose in the wilderness.
Step-by-step explanation:
The book in which a boy climbs a tree to try and hide is "Hatchet". In this novel by Gary Paulsen, the main character Brian, who is stranded in the wilderness after a plane crash, climbs a tree to escape from a moose that is threatening him. Brian uses the tree as a place of safety and observation until the moose eventually leaves.
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