From an email by Jocie to the Botany Group on August 26.
There are many beautiful, intriguing aquatic plants that often escape our notice, especially since some are totally submerged (maybe botanical snorkeling would be fun?). Here are a few aquatic plants [click a photo to enlarge it]. If any of you have seen/photographed any more aquatics lately send them on to me to share with the group.
- Water lobelia (Lobelia dortmanna). This grows in shallow water along lake and pond edges. The leaves form a submerged basal rosette, and the white or pale blue flowers bloom above the water surface. From iNaturalist, most records are from lakes in the Campbell River and Quadra Island area and on the west side of the island. It is on the CV plant list, though I’m not sure where in the CV it grows. Photographed here from Amor Lake (northwest of Campbell River).
- Bladderwort (Utricularia). Bladderwort has bright yellow flowers that bloom above the water surface in the summer, and thread-like leaves with floating, valve-lidded bladders that trap insects. Photographed here from Mallard Lake on Newcastle Island (near Nanaimo) in July. This one might be common bladderwort (Utricularia macrorhiza).
- White water-buttercup (Ranunculus aquatilis). Mandy sent in this photo from the Diver’s lake area this summer. This floating white buttercup grows in ponds and streams (low to mid elevations). I’ve also seen it in the stream that flows out of Helen MacKenzie Lake.
- Pondweeds (Potamogeton). There are many species of Potamogeton on Vancouver Island. Some are completely submerged, while others have leaves that float on the surface like lily pads, but more narrow and elongate. They can form extensive colonies, connected by rhizomes with fleshy, overwintering tubers. This one, photographed at Gosling Lake (northwest of Campbell River) might be the floating-leaved pondweed (Potamgeton natans).
- Water shield (Brasenia schreberi) and dulichium (Dulichium arundinaceum). Water shield looks like a small lily pad, but note that there is a central point of attachment of the stem on the leaf underside, unlike the pond lily. Dulichium is a common lake/pond sedge, with distinctive 3-ranked leaves.
- Dulichium close-up.
- Weird things at the bottom of the lake…I saw a strange worm-like thing at the bottom of Gosling Lake, with fine, whorled leaves. It was a metre or so underwater and I didn’t want to lean too far over in the canoe to photograph it (hence the bad photo). More investigation needed, but this looks like a milfoil. You have all heard of the highly invasive nightmare, Eurasian water-milfoil, that clogs many BC lakes, but there are several lesser known native milfoils. I’m wondering if this one might be Farwell’s milfoil (Myriophyllum farwellii)?? Any thoughts?
Aquatic plants are part of unique freshwater ecosystems, and I have the feeling that botanically speaking, there is a lot more to explore and document in the ponds and lakes in our area.
