I got your intention after getting closer but i didn't need pioneers to capture it. Used mortars to destroy the barbwire and used the trench after that as mortar pit.
Edit: Just finished a game on your map and I realy enjoyed it
but even when the fields look realistic DrunkinGambit was right, it feels a bit empty. Maybe you could just make the fields a bit smaller and add more fieldroads/ditches or hedgerows. In that case you could forget about adding objects to the fields itself.