How many letters does the top answer for “relating to an open fields; drowing in a field; growing in a field, or open ground.” have?

The most common answer is campestral (10 letters).

Crossword clue: relating to an open fields; drowing in a field; growing in a field, or open ground.

2 answers found in Letterora's clue database (Wikidata facts, Open Trivia DB, WordNet and Webster definitions — all licensed sources).

campestral 10 letters web-def

of fields or open country

campestrian 11 letters web-def

Relating to an open fields; drowing in a field; growing in a field, or open ground.