Walking through the trees in the park I've noticed there's a lot of white fluffy stuff on the ground, it's also blowing in the breeze. It looks a bit like cotton wool. What tree would this white fluffy stuff be coming from? Regards, Tezzer.
Like alan, I was about to suggest the poplar tree too.
Another likely plant is willow herb, I pulled a few of these plants, growing as weeds in a shrub bed this morning and got my trousers covered in the fluffy stuff.