365 Urban Species. #334: Wall Moss

[urbpan]

Photo by urbpan

Urban species #334: Wall moss Tortula muralis

This is another one of those "it could be this one" identifications. Tortula muralis is a moss with a growth form resembling a cushion. It is known to grow on concrete and mortar--a rarity among mosses, since they usually avoid alkaline substrates. It resists dessication, and so can survive in variably wet and dry climates like that of New England. It is also known to be resistant to toxic elements and pollution, and is one of the more common urban mosses. This one could be Tortula muralis. Alas, to properly identify a moss, one must use characteristics not visible in this photograph.

Mosses are evolutionarily primitive plants, meaning that they never evolved many of the features that we usually associate with plants. They have no roots, but instead adhere to their substrate with sticky filaments. They have no vascular system--no way to move water and nutrients within their thin tissues, and so require rain and external moisture to do this for them. They do not have flowers, fruit, or seeds. Male plants produce two-flagellated sperm that swim through the rainwater to fertilize the female moss plants. Recent studies have shown that springtails help to transport these sperm cells in some cases. The mating results in spores, which then are released to colonize new substrate.

Mosses are pioneer organisms, many species growing on bare surfaces. When mosses die, their tissues become soil, and eventually provide habitat for other plants. In cities in the Pacific Northwest and other very wet areas, moss growth can be pervasive and truly impressive.

For more on urban mosses and other bryophytes: http://www-biol.paisley.ac.uk/courses/silverside/PCE/PCEUrbanB.html

Comments

[aemiis-zoo.livejournal.com]

In cities in the Pacific Northwest and other very wet areas, moss growth can be pervasive and truly impressive.

Yes it can!

Why do people always get lost in the forest in Oregon? Because the moss grows all around the tree! ;-)

[treeclimber47.livejournal.com]

Many of the older garages in the Boston area are built with a cast cement cinderblock that was made to look like cut stone blocks. The wall moss loves to grow on garages built with this block. A while back I climbed up on to the flat roof of an old garage to look at the moss that covered the north wall and part of the roof. I sat in the moss and put my hand on it and felt a tingling electrical current through my fingers. I immediately jumped down. It's possible that there was some exposed wire in the garage and that the moist cinderblock and moss were "live". Or is it possible that there was some chemical reaction occuring with a large area of wet moss on rotting cement that was generating a slight electrical charge? Anyone ever have a "shocking" experience with moss?

[ndozo.livejournal.com]

It sounds like you did the right thing and you may have avoided a bad shock. Just about anytime you feel a tingle of electricity where it shouldn't be, even through your shoes, getting away is the safest course. I like the idea of electric moss though.