The most common and most likely answer to this crossword clue is the 7 letter word ACACIAS
I've seen this crossword clue in The Guardian
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More clues leading to the result ACACIAS
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The straight part
We know that "Wattles" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case wattles = acacias.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 ACACIAS mean?
ACACIAS noun- A shrub or tree of the tribe Acacieae.
- The thickened or dried juice of several species in Acacieae, in particular Vachellia nilotica (syn. Acacia nilotica), the Egyptian acacia.
- A false acacia; robinia tree, Robinia pseudoacacia.
- Gum arabic; gum acacia.
- Any of several related trees, such as the locust tree.
- A light to moderate greenish yellow with a hint of red.
- (history) A roll or bag, filled with dust, borne by Byzantine emperors, as a memento of mortality. It is represented on medals.