I might be wrong, but I had thought the fast-growing Willow was the principle cause of mossland drying out. That's what I was told at Risley Moss some years back when they could afford to remove most of them
When I first moved into Astley Green thirty odd years ago there were literally hundreds of Silver Birch trees on Astley Moss SSSI and Bedford Moss. Lancashire Wildlife Trust have over the years removed virtually all off these trees over a massive area,as apparently they help to dry out the mossland and prevent sphagnum moss regenerating. As far as I'm aware Willow Tits rely a greatly on Silver Birch trees to provide nesting sites as the trees are relatively easy to excavate nest holes in. I'm just wondering if this is why they have declined enormously down there? It seems a bit strange to me that LWT are touting the area as one of their last strongholds when they have denuded the area of suitable nesting trees,and have quite probably helped in their decline.