365 Urban Species. #179: Amethyst Deceiver

[urbpan]

Photos by cottonmanifesto. Location: Hillside of onramp between Jamaicaway and Olmsted Park, Boston.

Urban species #179: Amethyst deceiver

Most familiar urban fungi (and likewise, most fungus species represented in this project) are wood-digesting fungi. They live as filaments in dead wood, feeding on their surroundings, and fruiting as mushrooms or brackets when it is time to reproduce. But there is another major lifestyle adopted by members of kingdom fungi, that is much more rarely seen in the city. We all must learn the word "mycorrhizal," (Mike-o-Rise-ul) which describes how certain fungus species live. A great many fungi live in mycorrhizal association with plants. They live amongst the roots of plants, feeding on the carbohydrates the plants make from sunlight, while helping the roots obtain more water and nutrients.

Many colorful and interesting mushrooms grow from mycorrhizal fungi that associate with tree roots. This symbiosis takes time to develop, and the short life span of urban trees (5 to 10 years for a tree planted in the city) means that the tree may die before it and the fungus can find each other. Also, urban soil is a substance constantly on the move, being dug out of one place and trucked into another, which poses another obstacle to mycorrhizae. Only in those places in the city where the soil is stable and healthy, and the trees have lived a long time, do we find mycorrhizal mushrooms.

This group of amethyst deceivers was growing along the edge of a traffic onramp, between the Jamaicaway and the beginning of Olmsted park. A few moderately old red oaks loom nearby. If you didn't know that the amethyst deceiver was mycorrhizal, you wouldn't think they had anything to do with the oak trees. But if not for the oaks, these exquisite little gems wouldn't be there at all.

The amethyst deceiver is a member of the genus Laccaria, which includes L. laccata, a highly variable mushroom easily confused with a number of other species. Thus, L. laccata is known as the deceiver. L. amethystea was once thought to be a variety of L. laccata, but has been granted full species designation. That complicated but pedestrian story is how this pretty little mushroom acquired a name that makes it sound like a gothic rock band.

Comments

[drocera.livejournal.com]

Pretty! Reminds me of a rose.

[http://users.livejournal.com/purplebunnie_/]

My god that's pretty.

[http://users.livejournal.com/purplebunnie_/]

Would you or the lady mind if I used this photo for... well, for something random.

[cottonmanifesto.livejournal.com]

as long as it's not for black magic or profit, i'm cool with it.

What a team!

[momomom.livejournal.com]

That is fascinating about urban soil mobility and the short tree life spans decreasing mycorrhizal fungi. See it isn't just cottonmanifesto's photos!

[ritaxis.livejournal.com]

How do you come by that figure for the lifespan of urban trees? I'm thinking my own pale little anecdotal experience doesn't jibe with that. Is that a difference between Western and Eastern cities, or am I wrong about the trees in SF, Oakland, and San Jose? -- I mean I could have an error of observation based on missing all the little baby trees that don't make it and are replaced regularly. But that's not what my memory provides me with.

[urbpan.livejournal.com]

I got the 5 year figure from a soil fungus researcher from Guelph, speaking about mycorryzae. He said 5 years was the average life span of a tree in Toronto. The USDA states the figure of "less than ten years."

I think the key concept here is average. For every 50 year old Eucalyptus is the Presidio, there are probably countless saplings planted that die in as year. I suspect its much worse in Northern cities than in southern or western. We salt our sidewalks up here.

[ritaxis.livejournal.com]

I bet the salt is a big factor. Also, and because of that, there's probably a huge difference between park-and-plaza trees and regular street trees.

The eucalyptus (http://www.shapingsf.org/ezine/ecology/presidioframe.html) in the Presidio (http://www.presidio.gov/About/Post/AugSep2003/ForestFall2003.htm") are more like a hundred years old. The whole forest there, having been planted in one big flurry of planting in the 1880s-1890s, is reaching the end of its lifespan. Before the Army planted the trees, the Presidio was a magnificent bleak landscape of dunes and scrub.

[harrietbrown.livejournal.com]

Truly cottonmanifesto's powers of observation are keen, to find that little fungi apparently situated under grass. You guys, you're amazing! So is the nature that you photograph and write about.

Hey, I went camping over the weekend in New Jersey and saw: a great blue heron, a raccoon and a doe. Unfortunately, I was not armed with my disposable camera.

[cottonmanifesto.livejournal.com]

fortunately, it was bright purple and easy to see - also, it was right near the st. john's wort. :)

the rule of life seems to be that if you don't have your camera, you're bound to see something really cool.

[silvaerina-tael.livejournal.com]

These are spectacular. There is this rather small white, as in moon pale, mushroom growing near the roots of a couple maples in Halifax, NS. I'll try to post a picture within the next couple days, if possible. I suspect that trees in and around Halifax are quite a bit longer lived than they are in Toronto, and the soil beds aren't anywhere near as disturbed as much, which allows the fungal associations to grow.

beautiful

[(Anonymous)]

Hi,

Beautiful picture! I found some of these once.

Please could I have permission to use this image for a site of mine for a short while(I plan to use my own photos when I have more. It is called "La Nouvelle Mode" and dedicated to art, music, food and alternative lifestyle. I'm just getting up and running but can send you a link shortly when it is up. If this is ok please tell me how you would like to be credited / linked.

Thanks! Tom.

Re: beautiful

[cottonmanifesto.livejournal.com]

Hi Tom,

I took that picture and I'd be pleased if you'd use it. Please email me at cottonmanifesto at gmail dot com for more information.