Tree house perhaps of frontier days (3,5)

I believe the answer is:

log cabin

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'tree house' is the definition.
'log cabin' can be an answer for 'house' (log cabin is a kind of house). I am unsure of the 'tree' bit.

I can't explain the remainder of the clue.

Can you help me to learn more?

(Other definitions for log cabin that I've seen before include "Pioneer's hut" , "small dwelling" , "Hut, as in the Wild West" , "Wooden home" , "Simple dwelling" .)

I've seen this clue in The Globe and Mail.

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