|Crustose lichen (and a few leaves of a foliose lichen)|
Inspired by NPR's Science Friday video, I have become a fierce lichen hunter. I cannot walk passed a tree or fence without scanning it for my prey. I take my equipment EVERYWHERE (ok, just my camera).
As you can learn in the Science Friday video, lichen is a symbiotic lifestyle made up of three components: fungi, algae, and bacteria. The fungus harvests algae, which can create energy from sunlight. The role of the bacteria is unknown at present.
There are three types of lichen: foliose, fruticose, and crustose. The foliose has a leafy texture (pictured to the right). Fruticose looks like a little bush (on left) and I have only seen this once. Crustose (pictured above), the one I spot most often, looks like a crust.
Lichen can grow on trees, moss, soil, rocks, or human-made substrates if they sit still long enough in right conditions. I have had the most luck at the historic Congressional Cemetery but have photographed some beautiful specimens at the National Zoo and Kenilworth Park and Aquatic Gardens. It is also important to note that I have found some beautiful lichen in my neighborhood (like the picture at the top). You can see more photos on my flickr page.
It is impossible for me to conceal my excitement for lichen when I feel I am part of a secret society. Membership has given me the tools to notice the contour of gravestones and buildings and appreciate how messy and unexpected the world really is. As a lichen hunter, I exercise more, craving another afternoon walk with the possibility of seeing a new specimen. Most importantly, I am more of a biologist, appreciating and cataloging life.
Lichen represents something that you can see in your back yard that isn't very well known. Moon glow (chrysothrix chamaecyparicola) was described just last year, for example. There's a whole world out there for you to discover and you don’t have to be across the globe to do so. Lichen hunting encourages people to see the world around them. It promotes scientific discovery every day and brings science to a level where everyday people can do be involved.
Every time I see some growing, I smile to myself and enjoy this weird little thing. I hope you will too.