Lichen Schmiken

The foresters are at it again. Why oh why they wonder, are trees - this time, in Poland and Switzerland - dying from a fungus that used to be relatively benign? Oh, could it be that trees are weakened by climate change, as they speculate? Or even more likely, which they don't speculate, could it be that trees are weakened by atmospheric toxins from invisible, poisonous fossil and biofuel emissions??

Here's another story about fungal and insect attacks on trees, with links to lots of others in the sidebar. Why don't these foresters understand that healthy trees resist epidemics that are now rampant all over the world?

Could the same principle be true for lichen? In this amusing exchange with the Boston Museum of Science, I can't get them to answer a direct question:

rom: Magdalena Rabidou Subject: Lichen at the Museum of Science, Boston To: witsendnj@yahoo.com Date: Tuesday, April 13, 2010, 3:55 PM

Hello Gail, I am writing in response to the voice mail message you left yesterday. I am having a bit of difficulty finding the Lichen exhibit that you are referring to. If you don't mind giving me a bit more information about the exhibit, I may be able to answer your research request. Specifically: When did you see this exhibit at the museum? Do you remember where in the museum this exhibit was located? Do you remember any other artifacts that were also in this exhibit? If you can answer any of these questions, it would be very helpful. Thank you, Maggie Rabidou Administrative Assistant Educator Resource Center, Lyman Library Museum of Science Science Park Boston, MA 02114

From Wit's End:

I just saw this exhibit a couple of weeks ago. It's in an interactive section that also has drawers with bits of animal skeletons and stuffed taxidermy. There is an entire little red schoolhouse, and the preserved lichen is used as a puzzle for children to date the foundation of the schoolhouse by measuring the size of the lichen. I think its on the second floor overlooking the dinosaurs. My specific question is what was the resource used to state in the laminated notebook that the lichen grows at a steady rate of 1 mm per year. The other question I have is what is the source of the statement that lichens serve the purpose in nature of breaking down wood. This is quite important as every forester I've ever asked has told me they are harmless to trees. I don't see how they can simultaneously break down wood and be harmless to trees so I would like to find evidence that they are breaking down wood. If you scroll all the way down to the bottom of this blog post you will see pictures from your lichen exhibit. http://witsendnj.blogspot.com/2010/03/that-was-then-and-this-is-now.html Thank you so much for your trouble, Sincerely, Gail Zawacki

From: Magdalena Rabidou Subject: Re: Lichen at the Museum of Science, Boston To: "Wit's End" Date: Thursday, April 15, 2010, 10:52 AM Good morning Gail, Thank you for the additional information. I have been able to speak with one of my colleagues in exhibit development about this display. Unfortunately, the original creator of this display is no longer with the museum, and we are in the process of hunting down the source of these lichen references. In the meantime, my colleague offered the following explanation for the label copy. I can say that as far as I am aware, the lichens that break down wood are pretty specific to dead or dying wood. The (different) species that grow on living, healthy trees are not parasitic and use the trees only as a support and a source of moisture (which condenses on the bark). I hope this information is helpful. We will be sure to contact you when we learn more. Please feel free to forward along any additional questions you may have. Best, Maggie Rabidou Administrative Assistant Educator Resource Center, Lyman Library Museum of Science Science Park Boston, MA 02114

Wit's End wrote:

Dear Magdalena, I look forward to your sources for the exhibit! Can you ask your colleague to check the attached photos of trees and determine whether they must therefore constitute dead and/or dying wood based on the covering of lichen? Thank you, Gail

From:

"Magdalena Rabidou"

Add sender to Contacts

To:

"Wit's End"

Hi Gail,

My colleague does not consider herself an expert on lichen, but she wanted to direct you to a few resources

that may be more helpful: The Arnold Arboretum (http://arboretum.harvard.edu/) would be a good place to try

to ID them, also the Harvard University Herbarium in Cambridge (http://www.huh.harvard.edu/) and the

UMass Agricultural Experiment Station, which is now headquartered in Amherst

(http://www.ag.umass.edu/index.php/research).

If she can't remove actual samples to bring along to show them without injuring the bark of the tree

(and it looks like she has 2-3 different kinds at least from what I can see in the photos) she'll want to

take some good close-up photos to bring. Also, knowing the types of trees they're growing on might help, too.

Attached here is an online key for identifying basic lichen types....she might want to give the ID a try herself!

http://www.nhm.ac.uk/jdsml/nature-online/lichen-id-guide/lichens.dsml

I hope this helps you with your identification question.

Best, Maggie Rabidou