(Caution - stray surfers who drop in here - note: I am only an "intermediate" lichenologist - who welcomes constructive criticism and suggestions on some lichen identification)
Here we are - a year and a quarter into the 100 monads (1km squares) of my SD86 hectad survey i.e. the 10km square including Settle, of Settle Carlisle Railway fame.
and I am back at only the second monad.
SD8061.
I surveyed strip of 10 monads SD8060 to SD8069 last year (Rathmell to Helwith Bridge) and initially aimed to do the adjacent strip of 10 more SD8160 to SD8169 this year.
.
I am here today because, with the Coronavirus Lockup, I am doing lots of walks (Settle Wildflower) from home and from Settle - and today I am walking two miles downstream along the Ribble from Settle. And I have ended up back in SD8061
I am standing next to a large alder tree with an amazing covering of lichens on its trunk.
Amazing because the majority of the other trees around (and there are only about 16 large trees in the 1km square) have very few lichens.
 |
| The alder tree is to the right just off the picture. |
floods
- back in March 2019.
So the base of this tree was then standing in one foot of water - and the depressions under several feet.
Now we are in a drought.
I have only crept south into this monad by a few tens of meters. It is 8pm and I am making my way from the river Ribble back to the road, having photographed Settle Sewage works for a photo project. It is still light so I trundle across to an alder trunk not far off my route, lit up by the sun as it shines brightly. The sunlight, now parallel to the ground, dazzles into my eyes.
- First I notice the frilly Evernia /Ramalina on the trunk -
- and then that the trunk has abundant lichen nearly all the way round. In fact all the way round except for an area where cattle enjoy rubbing against it.
- and then that all the species seemed to be exceptionally isidiate or sorediate. (pictures at end.)
Is this really Parmelia saxatilis .. with so many isidia.. but no pseudocyphellae?
Is this a new species of Physcia with not just the tips of the lobes turned up and covered with soralia, but all the margin of the thallus?
Then I discover the Xanthoria polycarpa.
Shown here and magnified A LOT
Whoopee!. My first very own X. polycarpa in SD86
(The above tuft measures about 1/2 cm across. Note it does not have much thallus. The very common Xanthoria parietina is different because it is big and has lots of thallus and just a relative few fruiting bodies scattered across it.)
Some may wonder at my enthusiasm for finding this.
Yes, Allan Pentecost showed me a piece at Malham Tarn several years ago but a) That was "his" and b) It wasn't there the next year. - It is good to find a specimen for yourself.
(There is no dot for SD86 the distribution map of X. polycarpa in Dobson 2018), though I know that many records have been added to the BLS database since then)
Those of you who have taken part in the OPAL Lichen Air Survey will know that on printed card there are three species designated as "Indicators of heavy N Pollution" : Leafy Xanthoria (parietina) Cushion Xanthoria (polycarpa) and Physcia.
But what does Cushion Xanthoria look like? I have been constantly asking, over at least 6 years. "We don't get it round Settle".. Gallons, acres, swimming baths full of Xanthoria parietina, But no polycarpa.
In 2016 I found some polycarpa in Leeds in Meanwood Park preparing for the YNU students and blogged about it here
Well back to the X polycarpa - there are about dozen small pieces of it on the trunk. There are some other yellow lichens too.
Possibly Candelariella reflexa and Xanthoria ucrainica
I work my way round the trunk at nose level and find a piece of Flavoparmelia caperata
 |
| Flavoparmelia caperata |
and then - my pièce de résistance - Parmellina pastillifera. This is now the 9th monad I have found it in out of the 25 monad's I have looked at so far. (There we no records of this in the Hectad 6 years ago)
 |
| Parmelina pastillifera (pus Candelariella reflexa - the fine yellow powder bottom right) |
 |
| Close-up of Parmelina pastillifera You can clearly see the black button-on-stalk shaped isidia |
Just as I am leaving I noticed that the tree was actually growing over a (now totally dry) drainage ditch, which went undergound here. These drainage ditches must be very important in times of flooding. I wonder when they were built. 1700s? Late 1600s?So why such good cover on certain individual trees?
Hypotheses:
1.The lichens benefited from the cows rubbing the tree.
2.The lichens benefited from the drainage ditch
3. There is some magic fungal (maybe algal or bacterial) species present on this trunk - from which all the lichens on this trunk are benefitting. Maybe in some way the lichens help each other.
-----------------------------
Any suggestions?
--------------------------------------------------------
That evening I then got side-tracked into drainage ditches. (This one could easily be 250 or 300 years old - older than the tree)
The flat area between Settle and Hellifield used to be a glacial lake.
The Ribble used to flow East into the Aire near Hellifield, continuing east to the Ouse, Humber and North Sea. Ice sheets / glaciers flowed from the Lake District in the west and down the Ribble Valley. But at the end of the Ice age moraines and drumlins blocked the Ribble. It was a lake. It was diverted south west back to Preston.
See Long Preston Geotrail
And I got side tracked into into heights above sea level.
The current Ribble bank and my Alder tree are at 128 m above sea level. But heights are for another day.
--------------------------
Note till now I had only recorded 23 species in Monad SD8061
- It was only my second monad to record, when I was only attempting to visit a small sample area in each monad. (And let's face it.. floods did prevent further survey work... Also this monad does not seem very diverse habitat wise, and the areal photo only reveals about 15 big trees.) If I can get 6 NEW species out of the ones I found today then I will have 29 species, and the colour of the square can change on my map.
 |
| Xanthoria ucrainica? |
 |
| This picture is Ramalina farinosa |
 |
| What is this? (Lichen1) (plus ordinary Physcia tenella top right) |
 |
| I think this is Lecidella eleochroma |
 |
| Xanthoria ucrainica? |
 |
| Physcia tenella (including apothecium with black centre) -bit all the margin of the thallus seems to have soredia . Also Lecanora chlarotera, Xanthoria polycarpa, Melanelia glabratula (top left) Lecidella eleochroma (top middle left) |
 |
View of fields from Settle-Rathmell road. the alder tree is to the right just off the picture. Is s Ramalina farinacea being very frilly?  |
No comments:
Post a Comment