Wednesday, January 09, 2008

A Central Park LEO and Wisconsin Lichen

Photograph by Eleanor Tauber
The Long Eared Owls, or LEOs as they're called by many, are back in Central Park and so is Eleanor Tauber after a bit of a sabbatical. So once again we'll be treated to her photographs and reports from Central Park.

For those attempting to find the owls, just look for the group with binoculars all looking in the same spot. If they're looking at something else it will be worth looking anyway so do it too and if you have your binoculars, on request the birders will tell you where these guys were last seen.

And now it's back to the weird and wonderful world of lichen.

First off what is a lichen? It is a composite organism, that works symbiotically and is made up of members of as many as three Kingdoms.

The dominant main partner is fungus. But fungus has a problem because it can't make it's own food so it needs to do a little agriculture.. Many times they cultivate an algae and at others cyanobacteria and sometimes both.

And you thought lichen were just simple little guys that grew on things that didn't move much.

Above is a gray-green lichen that has been munched by a squirrel. It's much greener inside where the chlorophyll resides.

All sorts of creatures use Lichen for a variety of purposes, including humans who have used it as dye and in a pinch have eaten it, or that's what I'm told.

Photograph courtesy of Bureau of Land Management, Idaho
Many hummingbirds use it in nest building as do 50 other species of birds.
Spruce Grouse and Wild Turkeys eat it as do numerous mammal herbivores like Reindeer.

Lichen grows in a variety of patterns. This lobed, layered pattern above is called foliose. And oh, by the way the brighter green on the top edge is moss.

Speaking of moss, Spanish Moss that drapes over trees down south isn't moss at all it's a form of Frutitose pattern lichen. The fruititose pattern is the most three dimensional, it grows up like tiny shrubs, it grows in strands, it drapes down like Spanish Moss.

Whereas the brighter green in this lichen looks to be a different kind of lichen growing with the foliose gray-green model.

Lichen also comes in crustose that look rather like flat well connected crusts. In fact they are so well connected that in order to get a sample of a lichen that grows in crustose form off a rock, you have to chip part of the rock off.

Lichen because of it's varying partners has a variety of ways to reproduce. The above case is an Ascomycete and therefore it has round fruiting bodies or apothecia which produce spores. In this model they look a bit like miniature octopus suckers.

Take a look at this lichen. There is a brighter green which isn't moss and also a purple.

At first I thought perhaps these varying colors were other species of lichen but look how the edge of the purple-pink colored lichen lobe merges into gray-green.
Actually not only is lichen weird it's also quite mysterious.
Lichenologist Trevor Goward, tried this statement to simplify things. "Lichens are fungi that have discovered agriculture."
Donegal Browne

1 comment:

Anonymous said...

Donegal, I have to tell you I've been walking past lichen all my life and never paid it any mind at all. Thank you for opening a whole new world of beautiful growing colors and shapes. I'll never walk by again without taking notice. Thank you.