Tall, evergreen conifers with colours around the timber (8)
I believe the answer is:
redwoods
'tall evergreen conifers' is the definition.
The definition and answer can be both plants as well as being plural nouns.
Maybe you can see an association between them that I can't see?
'colours around the timber' is the wordplay.
'colours' becomes 'reds' (red is a kind of colour).
'around' means one lot of letters goes inside another.
'the timber' becomes 'wood' (I've seen this before).
'reds' enclosing 'wood' is 'REDWOODS'.
'with' is the link.
Can you help me to learn more?
(Other definitions for redwoods that I've seen before include "Giant trees" , "Tall sequoia trees" .)