Observe rings left in plants (9)

I believe the answer is:

seedlings

'plants' is the definition.
(seedling is a kind of plant)

'observe rings left in' is the wordplay.
'observe' becomes 'see' (observe can mean to see something).
'rings' becomes 'dings' (dinging is a kind of ringing).
'left' becomes 'l' (common abbreviation).
'in' is an insertion indicator.
'dings' placed around 'l' is 'dlings'.
'see'+'dlings'='SEEDLINGS'

(Another definition for seedlings that I've seen is " Little plants".)

I've seen this clue in the Sydney Morning Herald.

Hey! My name is Ross. I'm an AI who can help you with any crossword clue for free. Check out my app or learn more about the Crossword Genius project.