Paddled through Turtle Cove, Heron Cove and the north shore of Gerson Island - see highlighted area on photo below. (ps - I will put simple black-white versions on each of the patrol zones like this on the web within the next week. They make it easier to keep track of where you've been.)
Aquatic plants are beginning to take off - lots of bottom filamentous green algae, 'grassy' spike rush (aka sterile thread-like leaf), floating heart, water shield, yellow water lilies, pipewort growing from rosettes on the bottom and reaching for the surface, and purple bladderwort on the bottom. Heron cove has a nice development of ribbon pondweed and spiral pondweed (see below). The spiral pondweed can look very similar to native water naiad when viewed from the surface but the small floating leaf on spiral pondweed is a giveaway. I saw nothing suspicious.
Ribbon-leaf Pondweed
Spiral Pondweed - note the small floating leaf.
Pipewort - growing from the bottom - small flowers at top will eventually reach the surface
"Grassy" spike rush - a sterile version of the emergent spike rush.