schmutz from our black roof

This amount of deposition clogged our rain gauge on our control black roof in less than 3 months. Without testing I can only imagine that it is a combination of deposition and roof decomposition.

If we got this much accumulation from our 16 square foot experiment, imagine how much would be expelled from a roof that was to scale. In all fairness, some media and organic matter was also observed in gauges on our greened platforms, but not to this extent.