Saturday, March 29, 2008

White tipped bristle moss Orthotrichum diaphanum

I am an amateur naturalist trying to learn something about everything living in my garden.

Photo 1 shows another of my garden-wall-top's community of mosses. For this photo I was fortunate to be able to borrow a fancy digital camera. I'm most impressed with the close-up ability, as compared with the results from my own humble little 'point and click' camera, normally responsible for the snaps on this site. The Walloon bank balance may need to take a hit at some point!

Photo 2 (click to enlarge) shows a 40x magnified view of a single leaf. Distinguishing features are the circular leaf cells, the central vein that fades out just before the end of the leaf and the 'recurving' (folding over) of the leaf edge. Another obvious feature is the long, white 'hyaline' (=clear) hair at the end of the leaf. Quite a number of mosses sport such hairs (see my previous postings on S.intermedia, G.pulvinata and T.muralis for example). A pure guess on my part is that these hairs act as condensation sites for droplets of dew, thereby helping the moss to collect water. I've no evidence for this however. Can anyone comment? Anyway, regardless of their purpose, these features taken all together identify my moss as Orthotrichum diaphanum in my trusty copy of British Mosses and Liverworts (Watson, Cambridge).

For those of you unfamiliar with the art of moss identification (which included me when I began this blog a year ago ) clicking on 'moss' under the 'labels' menu on the left this screen and scrolling down, you'll easily be able to compare the leaf shapes of the different species I've blogged so far. You'll see that far from being all the same, different species of moss really do have their own individual and characteristic leaf features (some short and fat; others long and thin; some with hairs; some without etc.) - a strong aid to their identification.

O. diaphanum is a fairly common moss. According to my copy of The Moss Flora of Britain and Ireland (Smith, Cambridge) "[it] has been found on such unlikely materials as old linoleum, corrugated iron and tarmac". It is most common on trees and wooden fences.

Another feature obvious in photo 1 are my moss's brown setea (fruit stalks and capsules). The site of the Bryophytes and Buildings project - cataloging mosses in Edinburgh, Scotland - has some superb closeup photo's of the capsules and the 'peristome teeth' that are revealed when a capsule loses its lid. Experts use the shape and number of peristome teeth as another aid to species identification. I've read (though I can't remember where) that a moss's peristome teeth act as little mechanical devices, bending and flexing in response to passing air currents and changes in humidity and actually 'reaching inside' the capsule, 'scooping up' the spores therein, and flicking them out, away from the moss. Another of nature's tiny miracles!

2 comments:

R2K said...

I love moss!

Anonymous said...

A little off topic, Guys... I have a question. Two days ago I played at this site:
[url=http://www.rivalspot.com]Rivalspot.com - Wii Live Tournaments[/url]
They say you can play online Nhl2k game tournaments on any console for cash... had anyone tried that before? Looks like a cool idea...
Are there any other sites where you can play sports games for real moneys? I Googled and found only Bringit.com and Worldgaming.com but it looks these guys don't specialize in sport gamez. Any suggestions?