Species Feature #9, Ash-Tree Bolete

This feature is long overdue. In many ways the ash-tree bolete (Gyrodon merulioides) should have been Species Feature #1. Without this mushroom, my blog wouldn't exist. It was my first mycology success story: I encountered several specimens growing just outside my apartment. I had no idea what they were, but was able to get a tentative ID from one source. Since I was inexperienced, I really wanted corroboration - so I Googled the scientific name. At the time, one of the first search results took me to a post in this livejournal. It's written by a zoo employee in New England, and it planted the seed that grew into my idea for this blog. My introduction to this DC area blog by Laurel was, I suppose, the fertilizer. But it was my interest in G. merulioides that served as the soil. My blog's synthesis bears remarkable parallels to the ecological niche occupied by this species.

One largish specimen

Gyrodon merulioides Quick Facts

Common Name(s): ash-tree bolete

Taxonomic Breakdown:

• Kingdom - Fungi
• Subkingdom - Dikarya
• Phylum - Basidiomycota
• Subphylum - Agaricomycotina
• Class - Agaricomycetes
• Order - Boletales
• Family -Paxillaceae
• Genus - Gyrodon
• Species - merulioides

Range: I couldn't find information directly on the range of this species, but it is limited to the range of ash trees. Most commonly it is found under white ash, Fraxinus americana.

Just a small sampling of the hundreds of specimens I found one day in Silver Spring

Because of its proximity to white ash, the ash-tree bolete was long thought to be mycorrhizal.This is generally the case when a mushroom species is found exclusively under one species (or in this case, one related group of species) of tree. Yet the life of G. merulioides is more complex than that. It instead participates in a totally different symbiotic relationship - with a species of aphid which itself only feeds on ash trees. Meliarhizophagus fraxinifolii, according to this press release, fights predation by breeding wildly... so wildly, in fact, that some generations are born pregnant. I won't pretend to understand how this happens, but it adds one more layer of fascination to the scene.

Unfortunately, in the 1990s a fourth species entered the picture: the emerald ash borer (Agrilus planipennis), often referred to as simply EAB. This species of beetle decimates populations of ash trees, and threatens the entire genus. I have previously written about invasive species, taking the position that we are often too quick to label introduced species as damaging to their new environments. However, this seems like a clear-cut and very serious problem. Forests in this area can ill afford the loss of yet more tree species, and the EAB threatens several, and no North American species of ash tree has yet shown effective resistance to infestation. Lose the trees, and this biome loses the aphid and the mushroom mentioned above. Lose the aphid, and its predators lose a food source which rapidly replenishes itself.

Collecting spores.

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This mushroom is easy to identify if one knows what to look for. From above, the irregular, leathery, brown caps can be easy to miss, but once seen these alone are a good indicator of what you're looking at. The stem is lateral and often not very substantial. Underneath, the pore surface is a solid yellow with hexagonal pores. The light yellow (sometimes white) flesh of this bolete, like that of many boletes, bruises blue. A spore print usually isn't necessary for identification, but if taken it will appear olive brown. If you're unsure, look around for ash trees.

Note the blue bruising, and how the pores peel away from the flesh as a discreet layer.

Challenge Complete!

I had to rent some wheels this time - my own bike was out of
commission. A part is on order...

The Naturalism on Speed Challenge is complete! I left for vacation last weekend just two species short of my goal of 100. The five new species I was able to add while cruising Highway 12 on the Outer Banks fell short of my lofty ambitions for the trip (after all, it's a completely different environment) but were more than enough to put me over the top. The new additions are not likely to be seen in the DC suburbs (though I have seen laughing gulls this far inland). While that makes them a little off-topic for the blog they're well within the rules of the challenge. Speaking of rules, I'll recap. The basic premise is to identify species from a moving bicycle. To keep this different from simply identifying wildlife in general, I imposed the following five restrictions:

1. Listed species must be identified to species while riding, with certainty. 
2. No unnatural stops are permitted. 
3. Retroactive identification is also not permitted. 
4. Domesticated animals (and humans) do not count. 
5. Plants which grow at my apartment complex or other very familiar areas (my workplace, my parents' house, etc) are ineligible.

Species #99 - Laughing Gull (Leucophaeus atricilla)

Species # 100 - Sea Oats (Uniola paniculata)

Species # 101 - Brown Pelican (Pelecanus occidentalis)

Species # 102 - Adam's needle (Yucca filamentosa)

 Not pictured: Species # 103 - American beachgrass (Ammophila breviligulata)

This brings me to a final count of 103 species: 58 plants, 23 birds, 11 mammals, 5 fungi, 4 insects, and 2 reptiles. "Final" is a bit of a lie, because I do intend to keep adding to this list as I continue to cycle and to explore the natural world. The marriage of  these two hobbies has been too great an experience to discontinue simply because I reached an arbitrary milestone.

Hike from the New Digs

Most folks reading this already know, but I moved a few weeks ago. It wasn't far, so exploring the neighborhood is really more a matter of seeing the same neighborhood from a slightly different perspective. Still, it's been interesting seeing nature from this new vantage point. I have an altered bike route to work, the grounds of the new apartment are landscaped differently, and the surrounding area is a little more residential. I'm still close to most of the same parks and green spaces, and yet the slight shift in perspective seems to have shaken up my mindset enough that different details stand out.

I noticed this last weekend when taking my first long hike from the new base of operations. It wound through some of the same areas of Rock Creek Park I have blogged about before. I returned up the same section of East-West Highway I used to live on. Yet this hike was different than any previous ones in terms of which living things stood out to me. The next day I took an out-and-back bike ride along Sligo Creek Trail - a ride which allowed me to add about ten new species to my Naturalism on Speed challenge. It's been quite a while since I added more than two or three after a single ride.

A flowering plant along Portal Drive was the first new thing to draw my attention. Its leaves were shaped like a child's drawing of a Christmas tree, and its small flowers ranged from pale violet to white. It had a row of spines along the stem, and these occurred in pairs opposite one another. These spines were also present on the underside of the leaf. (Wow! Typing this paragraph has reminded me just how much plant life review I need if I want to appear knowledgeable. I just don't have the biological vocabulary to be precise.) I've no idea what this plant might be, so if anyone can ID it from the photo below please leave a comment.

Mystery Plant #1.

The next "new" thing I noticed is probably best explained by a picture. It's something I see all the time, but last weekend was the first time I thought it might make a nice photo.

This is a reminder that oyster mushrooms are appetizing to more than just humans. Also, it's hard to tell from this photo but that was one enormous slug.

Mystery plants were a theme of the day. Number two was a ground-covering plant lining much of the trail through the park. I see this plant often but until lat weekend my mind filed it as part of the background, and therefore not an item of interest. It had a long whiplike flower and large leaves relative to the overall plant size. Once I noticed it I saw that it was quite prevalent throughout the northern section of the park. Again, if you have any clue as to this one's identity from the photo below please let me know!

Mystery Plant #2

It was while climbing THE HILL on the way back that I collected my one big mushroom find of the day. This was a large patch of Chlorophyllum molybdites, sometimes known as the green-spored parasol since *dramatic pause* it looks like a parasol mushroom and has green spores. This mushroom is an old friend and among the first handful I learned to reliably identify. The "new" of this encounter was that I hadn't before considered the narrow strip of grass between the main lanes of East-West Highway and the access road as fertile ground for a mushroom search. Looking back, though, these aren't the first mushrooms I've seen there.

Franklin didn't care one bit about the mushrooms, but it sure looks like he's proud of something here, doesn't it?

This brings me to my final mystery plant (well, there was a mystery tree as well but I didn't take any pictures). This plant was enormous for a non-woody plant. It stood easily eight feet high, and likely closer to ten. Its leaves were each larger than my head. I can't really think of any identifying features other than its size, so I'll just show you. If you know what this thing is, you know what to do.

The leaves of Mystery Plant #3

 

 

 

Mystery Plant #3 in all its monstrous glory.

Coming down the home stretch of the hike, I started seeing a plant I'm familiar with but had never really noticed in Silver Spring: pokeweed. This stuff has berries that start as white flowers which turn green and then a deep, nasty-staining purple. I'm confident enough that the species is American pokeweed (Phytolacca americana) that I counted it in my little challenge when I saw more of it the next day.

Pokeweed in the green (and thus not yet fatal to garments) stage.

I guess the takeaway from last week's experience is that however familiar I think I am with the natural environment, there's always something there I hadn't noticed before. Whether my move had anything to do with my shift in perception is immaterial - what matters is that the diversity of life is great enough to continually provide new surprises.