Crossword Genius

Call London borough over destruction of trees (4-7)

Ross

I believe the answer is:

ring-barking

I'm a little stuck... Click here to teach me more about this clue!

'borough over destruction of trees' is the definition.
I can't tell whether this definition defines the answer.

'call london' is the wordplay.
'call' becomes 'ring' (telephone call).
'london' becomes 'barking' (I can't explain this - if you can you should give a lot more credence to this answer).
'ring'+'barking'='RING-BARKING'

Can you help me to learn more?

I've seen this clue in the Sydney Morning Herald.
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