Dug into strip of earth, in favour of starting (6)
I believe the answer is:
probed
'dug into' is the definition.
('probe' can be a synonym of 'dig into')
'strip of earth in favour of starting' is the wordplay.
'strip of earth' becomes 'bed' (I can't explain this - if you can you should believe this answer much more).
'in favour of' becomes 'pro' (being pro a particular cause).
'starting' says to put letters next to each other.
'bed' put after 'pro' is 'PROBED'.
Can you help me to learn more?
(Other definitions for probed that I've seen before include "Physically examined" , "Searched" , "Questioned or examined thoroughly and closely" , "Investigating closely" , "Investigated closely as dentist does a tooth" .)