pollen on the roof

It actually clogged the rain gauges.  Only on the black roof, though. No, that is not dust; this is also after a 0.5 inch rain- before this there was a yellow film coating the roof.
?Greenroofs as allergy mitigators???? Hah!

proposal seminar!

Here's a link to the proposal seminar I gave as part of the University of MD (College Park)'s Plant Sciences department