perkolator
Songster
No real input, but if I was collecting rainwater under trees I'd likely have one of the filtration systems that people use for their rain barrels. Basically a fancy sediment trap with a filter, could probably even DIY it. At my last house we had gutters on full perimeter and a japanese maple that loved to put out leaves and seeds - I used these coarse foam gutter inserts for filtering out leaves in the rain gutters, seemed to work pretty well as long as you clean them out seasonally. If you don't, the accumulation of leaves decomposing on top collapses the foam.
