The most common and most likely answer to this crossword clue is the 9 letter word CHESTNUTS
C
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More clues leading to the result CHESTNUTS
- Heads below box trees
- Horses displaying revolutionary tricks going backwards
- Xmas food box with bit of tuck that student group wraps
- The stale and overfamiliar 22 across on Revolutionary Road
- Box with bitd of food – they may seem stale
- Boxes must contain fruit for horses
- Old jokes they crack at Christmas
- Clichés — teachers appearing in cases
- Box with crazy old jokes?
- Maybe they are no longer funny trees
Buddy explains!

The straight part
We know that "trees" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case trees = chestnuts.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 CHESTNUTS mean?
CHESTNUTS noun- A tree or shrub of the genus Castanea.
- The nut of this tree or shrub.
- A dark, reddish-brown colour, as seen on the fruit of the chestnut tree.
- A reddish-brown horse.
- The wood of a chestnut tree.
- An old joke; a worn-out meme, phrase, ploy, etc. so often repeated as to have grown tiresome or ineffective (often in the phrase "old chestnut").
- A round or oval horny plate found on the inner side of the leg of a horse or other animal, similar to a birthmark on a human.
- The horse-chestnut.