Why are they dead? If it was a disease or a pest infestation that may affect anything you try to grow up them as well as how long the remaining trunks are likely to be stable and not rot or fall over.
Also the kind of soil you have, the variety of tree and their root spread and roughly where you are - weather exposure etc - will make a difference to what can grow.
Vendée - 20kms from Atlantic coast.
"The price good men (and women) pay for indifference to public affairs is to be ruled by evil men (and women)."
Posts
Also the kind of soil you have, the variety of tree and their root spread and roughly where you are - weather exposure etc - will make a difference to what can grow.
I think we need to see some photos please .... that way we'll have a better idea of what you have to deal with and the options available to you.
Gardening in Central Norfolk on improved gritty moraine over chalk ... free-draining.