The most common and most likely answer to this crossword clue is the 9 letter word LUMBERMAN
I've seen this crossword clue in Independent
L
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M
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More clues leading to the result LUMBERMAN
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The straight part
We know that "Forestry worker" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case forestry worker = lumberman.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.
What does LUMBERMAN mean?
LUMBERMAN noun- A man involved in the production or sale of lumber; a lumberjack or logger.