Huge growth ruined Saudi golf, ending in disaster (7,3)

I believe the answer is:

douglas fir

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'huge growth' is the definition.
Although both the answer and definition are singular nouns, I don't see how they can define each other.

'ruined saudi golf ending in disaster' is the wordplay.
'ruined' is an anagram indicator.
'ending in' says to take the final letters.
The final letter of 'disaster' is 'r'.
'saudi'+'golf'='saudigolf'
'saudigolf' anagrammed gives 'douglasfi'.
'douglasfi'+'r'='DOUGLAS FIR'

Can you help me to learn more?

(Another definition for douglas fir that I've seen is " tree".)

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