Sunday, September 15, 2013

Failed searches and streamer weed

click photo to enlarge
Most web searches that I make are successful. A wide range of information is available on the internet, much of it in great depth, and often in at least four forms - text, images, video and audio. Moreover, I've gone out of my way to become familiar with a reasonably wide range of search techniques. Consequently it is relatively unusual for me to fail in a quest for facts about a topic. But failures do happen. Often this is because the subject is arcane. Or it may be obscure or of interest to only a very small minority of people and therefore little documented. Some failures appear to be successes until you discover that what you took to be fact turns out to be someone's unintentionally erroneous posting or just plain wrong through the poster's ignorance.

However, the other day I spent a long time searching for some information and drew a blank. I was trying to find out the name of the plant shown in today's photograph. It is a common river plant that I see regularly in many lowland rivers, and its very prominence suggest that it will be well documented. It probably is, but not in a form that allows me to assign it a Latin name. Fishermen call it (and several other plants that grow in a similar location and fashion) "streamer weed". That is descriptive of the ribbon-like leaves that undulate sinuously in the current. But, to fix its identity with the species' Latin name proved impossible for me. It may be a form of Ranunculus, Glyceria or some other equally common river-growing plant. The problem is that I can't match a photograph that looks like mine with any other reliably labelled image. Then there's the fact that most botanical illustrations use the flower as an identifier and this has clearly passed its flowering season. In fact, I've found very few shots of the plant that emphasise its attractive, twisting form, except a couple by other photographers similarly fascinated

From previous experience I imagine that I'll search again and a route to the right answer that was formerly closed, or which I missed, will open up. Until then streamer weed it is!

photograph and text © Tony Boughen

Camera: Sony RX100
Mode: Aperture Priority
Focal Length: 37.1mm (100mm - 35mm equiv.)
F No: f5.6
Shutter Speed: 1/125
ISO: 200
Exposure Compensation:  -0.3 EV
Image Stabilisation: On