Cathleen Adams, a new member who was one of Larry's students at the clinic, just sent me this information on the didymo algae strain, an invasive species that is spreading rapidly in some parts of the US. They are slightly big so I uploaded them to my domain and linked them here. (The white paper is over 2 MBs and the handout is about one M

.
If you don't have the stamina for the white paper, at least read the handout. It stresses the importance of cleaning, or at least drying your gear before taking it from one watershed to another.
White Paper
http://www.hanleyanddenile.net/EPAWhitePaperDidymo.pdf
handout
http://www.hanleyanddenile.net/EPAHandoutDidymo.doc
Hanley