A piece of wood traveller put up as garden structure (7)
I believe the answer is:
pergola
'garden structure' is the definition.
(I've seen this before)
'a piece of wood traveller put up' is the wordplay.
'piece of wood' becomes 'log'.
'traveller' becomes 'rep' (travel company worker).
'put up' is a reversal indicator.
'a'+'log'+'rep'='alogrep'
'alogrep' written backwards gives 'PERGOLA'.
'as' is the link.
(Other definitions for pergola that I've seen before include "lattice" , "Arch for garden plants" , "Framework to support climbing plants" , "This'll support climbers" , "Horizontal trellis" .)