Friday, 25 September 2015

Arable fun

This afternoon Julian Woodman took me to see an organic arable field just west of Cardiff (ST1080). I was on school run duty so we had a 4 year old in tow, but that didn't spoil the fun of seeing lots of the crystalworts (both Riccia glauca and sorocarpa) which Julian had seen when he first visited the field a week or two ago. More exciting still was a fair abundance of hornwort rosettes, often mixed with the crystalworts. Neither of us had seen a hornwort before so we were rather chuffed (though Bethany was rather more interested in the shieldbugs and spiders).

I think these are probably Anthoceros agrestis, given the rosettes are small (0.6-0.8cm diameter) and this species is more likely than punctatus in the east of Wales, but I couldn't find any antheridia to confirm this. Any comments on whether it is safe to record this as agrestis would be welcome.

Anthoceros agrestis?
Young Anthoceros agrestis?
A species rich lump of arable earth

There was also a lot of Fossombronia sp. (lacking sporophytes) as well as Tortula truncata, Trichodon cylindricus, Dicranella staphylina and Bryum rubens, among other more generalist species such as Oxyrrhynchium hians.

Monday, 21 September 2015

Gwendraeth Fawr

An area of M23b-S5 transition on the floodplain of the Gwendraeth Fawr had a strong population of Amblystegium radicale in an otherwise bryo-poor marsh community. I've only seen this species a few times before and never growing as well or as erect as this, and with the largest leaves up to 1.7mm long (Smith gives max. as 1.4mm), confirmation or otherwise would be appreciated. The narrow, but long decurrent leaf bases seem to be key.

Willows along the adjacent disused canal/railway (now mostly wet woodland) supported locally frequent patches of fruiting Homalia trichomanoides, with occasional curly shoots of Sanionia uncinata intermixed.

Finally, an area of tightly grazed turf on what appears to be the remnant of an old tip was largely dominated by a Weissia  (photo below right) that had a few clusters of young sporophytes. The presence of frequent Bryum pallescens (with old and develping sporophytes), perhaps suggests this might be W. controversa var. densifolia, but the expanse of Weissia was more of a crust than the dense cushions I've seen at other sites. Again opinion would be welcome, but I suspect it will simply have to be logged as Weissia sp. A non-fruiting and indeterminate Cephaloziella (photo below left) was the only other frequent bryo at this interesting little area.

Sunday, 20 September 2015

Whiteford Bryum search

Nick Edwards kindly invited me down to me meet David Holyoak last Wednesday, who was carrying out a series of dune slack bryophyte surveys in Wales. It was good to spend a little time with the very affable Mr Holyoak before letting him get on with things, but not before he had shown us Bryum marratii and putative B. warneum in the 'new' slack. Very much looking forward to seeing David's final report.
David at the first putative Bryum warneum location
A patch of B. marratii at Whiteford from April 2012 (first found by Sam)
The material seen last week was fresher and greener, the spreading,
blunt-tipped leaves being very good characters to look for.

Friday, 18 September 2015

Glamorgan update

Dave Slade sent through what was hopefully the bulk of Sam's missing records this morning, which together with George's summer offerings, now gives us a pretty comprehensive dataset for modern (i.e. post 1999) recording effort in the county. I'm guessing like many of us Charles and Hilary have eased off bryophyte recording over the summer, but probably have some records to add from NPT. The updated tetrad map below does include a reasonable amount of older data which is now on my system, but I know there is still a more to be added. At least now anyone fancying a bit of square-bashing will know where to find 'sub-60' squares. We now have 205 squares with 60+ spp recorded, i.e. 33% of Glamorgan's 624 tetrads, so still plenty opportunities for exploration of virgin territory to be had.
Map below from the end of 2014 shows progress in 2015
Apologies for the lack of labels, but the plot below shows the number of records made annually (or rather those that are now on the MapMate system) since 1980, with pre-1980 records lumped:

Monday, 14 September 2015

Aphanorrhegma patens site

On Sunday morning I popped up to the site in ST1185 where Julian found the Aphanorrhegma patens. Sure enough it was widespread across the wetter, barer patches in the field shown in the photo below, along with abundant Riccia sorocarpa.

Various Persicaria were abundant and quite confusing. I could certainly see some plants of Small Water-pepper (P. minor)  among the commoner species, but was unsure about Tasteless Water-pepper (P. mitis). Julian and Tim Rich think they have some good candidate material for the latter from this same field, but it requires confirmation.

Thursday, 10 September 2015

Tiny moss query

I attended the Glamorgan Botany Group excursion to Gwaelod-y-garth on Sunday, but had to leave at lunchtime. I therefore missed the best finds of the day, both Persicaria minor and mitis found growing by a seasonal pool near the Taff in the afternoon.

Julian Woodman brought back a clod of earth from the same area as he had noticed a crystalwort growing in abundance. This proved to be Riccia sorocarpa, but the clod also contained plants of Trichodon cylindricus, Tortula truncata and a tiny, fruiting moss which I can't work out - see photo below (the Riccia gives an idea of how small it is). The leaves are strongly toothed and translucent. The round, brownish capsules are on very short setae.

I'll get some microscope photos if it's not possible to work out the species from the above. Thanks.

Sunday, 6 September 2015

Fossombronia wondraczekii

I was looking forward to ending a long hiatus on the blog with this post, but was delighted to see three other recent posts. It must be autumn!

I haven't done any serious bryo recording since the spring, but was pleased to see a healthy patch of Fossombronia on a wet, acidic cattle track on Pengwern Common (Gower) last Friday. This proved to be F. wondraczekii, which would perhaps have been the most likely species in this habitat - but it's a new one for me.


Friday, 4 September 2015

Weissia controversa var. densifolia

I rather like the way this colony is enveloping the base of a zinc-coated chain link fence on the boundary of Morriston golf course. The map below shows the number of records is slowly increasing and I'm sure it's fairly widespread if localised. It's worth checking poor soils under this type of fencing, under roadside crash barriers and drip zones under zinc roofing, these all being situations I have encountered the species.

Thermal photographs, a useful tool for mapping cliff face tufa habitats?

I often use temperature as an indicator for different water sources. Surface water, at least in the top meter or so, can vary from frozen to almost air temperature in the summer and cools from the surface down in rivers and lakes.  The sea may only reach about 17degrees if your lucky. However groundwater is often much more stable throughout the year, and a good rule of thumb is that groundwater, at least in Wales is about 11°C. Groundwater temperatures can be predicted by using the mean annual air temp (about 10°C) and adding 2-3°C for every 100m depth, so a groundwater from about 50m or so depth is likely to be around the 11-12°C mark. So armed with this – and my new toy – a FLIR C2 hand held thermal camera - I headed out to some cliff sections nearby.

Identifying groundwater seepages using thermal cameras is nothing new (see these slides from the EPA, 2008) however I am not sure it has been used for cliff face seepage mapping to identify bryophyte habitat/water supply –but then I could be wrong!

My aim was to see if the new camera could show temperature differences on a cliff face and perhaps identify groundwater seepages where tufa was forming (and bryophytes are living). Would this be any use for mapping or better understanding these habitats?

Below are my first few attempts, which I thought were worth sharing. The camera does show areas where groundwater seepage is occurring from the cliff, which correlate with the tufa and tufa mosses. 

There are a few problems; the camera only records the surface temperature and this will change as soon as the water seeps out of the cliff and starts to equilibrate with the air temperature.  In the summer this will have a warming effect and a cooling effect in the winter – thus choosing when to do this needs some thought. Perhaps repeat photography is needed throughout the year. The vegetation itself may alter the temperature as could small areas of shade. It would be useful to measure the water temperature in situ with a good old thermometer however these cliffs are just too dangerous to stand underneath. 

Since reading Barrys blog about cow pats I thought that thermal imaging would certainly show up the temperature of the fresh pats quite nicely, I wonder what they look like in the winter and for how long they maintain a temperature different to the ambient air temp– are they acting as microclimates for bryophytes? 

Happy for comments or suggestions.

DIGITAL PHOTOGRAPH: Cliff face groundwater seepage (west of Nash Point) with active tufa formation – Eucladium verticillatum and Didymondon tophaceus type habitat with lots of Maidenhair fern. 
THERMAL PHOTOGRAPH: Cliff face groundwater seepage (west of Nash Point) with active tufa formation – Eucladium verticillatum and Didymondon tophaceus type habitat with lots of Maidenhair fern.  The wet area is highlighted nicely (in the blue-purple colour) and is close to the estimated groundwater temperature of 11OC plus a bit as it was a warm day– although the effect of shade and vegetation on temperature is not known. 

DIGITAL PHOTOGRAPH: same again some Maidenhair fern with tufa bryophytes 
THERMAL PHOTOGRAPH: again showing up the groundwater seepage areas quite nicely. The seegage in this picture is warmer than the last, not sure why, could be multiple reasons. It is still however much cooler than the air temp on the day about 20oC.

Wednesday, 2 September 2015

Splachnum in Caerphilly

I've been keeping a casual eye open for cow pat bryos ever since Sam recorded Splachnum ampullaceum and S. sphaericum last winter. So you can imagine my joy when walking over Tair Carreg Moor today and finally encountered some Glamorgan Splachnum on a beautifully weathered cow pat.  In total during my small circuit I noted it on five different, widely scattered cow pats, all colonies being small patches of S. ampullaceum (Cruet Collar-moss). I did the same route two months back and saw nothing, so wonder if the flushes of fresh vegetative growth are a result of the wet August we’ve experienced?