Scandinavian chap hiding with father in the trees! (4)

I believe the answer is:

lars

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'scandinavian chap' is the definition.
'Lars' can be an answer for 'chap'. I'm unsure of the 'scandinavian' bit.

I cannot understand how the rest of the clue works.

Can you help me to learn more?

I've seen this clue in the Evening Standard.

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