Looking at lichen. Again.

The oldest living lichen, a map lichen, is estimated to be 9,500 years old. The lichens, like the mosses, grew here hundreds of millions of years before the first human ancestors rested on a mossy bank. I don't know whether these facts are comforting: life goes on, whatever challenges arise: or distressing; the lichens and mosses (and the cockroaches, too, they say) will be here when we're a faint memory.

These lichens are younger, no older than the trees they live on.

At least three, maybe four lichens, and a moss on the bark of an alder.

A beard lichen. It covers this bare shrub from top to bottom.

The tiny "pimples" on the bark are probably also lichens.

Lungwort, Lobaria pulmonaria. The easiest of all the lichens to identify.

Mostly moss, but where you find moss, there is usually lichen. Two lichen species here, maybe three.

Reindeer lichen is usually found on the ground or on logs. These cushion a rock face, along with mosses and ferns.

~~~~~~~~~~~~~

Los líquenes son organismos de larga vida. El que se considera el más viejo, un liquen geográfico, Rhizocarpon geographicum,  ya lleva 9.500 años de vida. Los líquenes, al igual que los musgos, crecían aquí cientos de millones de años antes de que el primero de nuestros ancestros se reclinara sobre una piedra cojinada con musgos. No sé si estos datos me traen consuelo: la vida persiste, no obstante los retos que surgen: o si provocan desaliento; los líquenes y musgos (y, se dice, las cucarachas) seguirán aquí cuando nosotros sean una memoria tenue.

Estos líquenes son más jóvenes; su edad se limita por la de los árboles sobre los cuales están creciendo.

1. Tres, o tal vez cuatro, líquenes en el tronco de un aliso rojo.
2. Un liquen "barba", Usnea sp. Cubre este arbusto desprovisto de hojas desde el suelo hasta la punta de las ramas.
3. Los pequeños botoncitos en la corteza probablemente sean líquenes también.
4. Lobaria pulmonaria. Este liquen grande se reconoce facilmente.
5. Musgos en una rama. Donde encuentras musgos, normalmente los acompañan algunos líquenes. Aquí se ven dos, o tal vez tres, especies de líquenes.
6. El liquen de reno casi siempre se encuentra en el suelo o encima de troncos tirados. Este se ha establecido sobre un peñasco, acompañado de musgos y helechos.

Chameleon lichen

After a few days of strong winds, the forest floors are littered with broken branches, dead leaves, conifer needles, and lichens; clumps and threads and whole branch-loads of lichens.

Two lichens; Lungwort and a beard lichen. On a Bigleaf maple mulch.

High on the trees, where the rain drains away quickly and the lichen is exposed to sunlight, the thallus is a mix of browns, from pale beige to dark chocolate brown, to a yellowish mid-brown. In the shade, where it's still dry, it's a paler greenish-grey. Tossed down here onto the wet ground, and then rained on, it turns a bright green on top, and a pale blue-grey on the underside.

The beard lichen, those pale threads mixed in with the lungwort, stay the same colour whatever the weather.

I didn't know this:

L. pulmonaria has the ability to form both vegetative propagation and sexual propagules at an age of about 25 years. ... Dispersal by vegetative propagules (via soredia or isidia) has been determined as the predominant mode of reproduction in L. pulmonaria. ...In this method, the protruding propagules become dry and brittle during the regular wet/dry cycles of the lichen, and can easily crumble off the thallus. These fragments may develop into new thalli, either at the same locale or at a new site after dispersal by wind or rain. (Wikipedia)

25 years! Lichen is slow-growing. How many years does it take to completely coat a tree, like the one I posted yesterday?