Courses to the bases of plants, I hear (6)
I believe the answer is:
routes
'courses' is the definition.
(I have seen 'regular courses' mean 'routes' so perhaps 'courses' could also mean 'routes')
'the bases of plants i hear' is the wordplay.
I cannot quite understand how this works, but
'the' could be 't' (the is pronounced as a 't' sound in some dialects) and 't' is found in the answer.
'of' could be 'o' and 'o' is found within the answer.
'plants' could be 'rues' (rue is a kind of plant) and 'rues' is present in the leftover letters.
This accounts for all the letters.
This may be the basis of the clue (or it may be nonsense).
'to' is the link.
Can you help me to learn more?
(Other definitions for routes that I've seen before include "Ways or courses of travel" , "Ways from A to B" , "Ways to go, roads" , "Ways to go for ouster" , "Established lines of travel" .)