The most common and most likely answer to this crossword clue is the 9 letter word CORNSTALK
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Buddy explains!

The straight part
We know that "likely to be seen in an American field" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case likely to be seen in an american field = cornstalk.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 CORNSTALK mean?
CORNSTALK noun- The tough, fibrous stalk of a corn (maize) plant, often ground for silage after harvest.
- A single specimen of a corn plant once past the seedling stage and which may, at maturity, bear multiple ears of corn.
- A non-indigenous person born in Australia.
- A non-indigenous native of New South Wales.