Not sure if any of these are an option for you.

I have a wood fence too.

I have 3 different ways along my wood fence to
keep the dogs in their yard.

cement pavers along the fence: more costly but
looks decent.


Dig a small trench along the fence and pour cement:
(cement does not touch fence)
My cement is old but it still works.


attach chicken wire to the botton of the fence letting 1 foot or so on the ground and covering it with railroad ties.
Doesn't look the best, but it is cheap and you can
use ground cover to hide it).