Saturday’s jaunt with Sue to Deepdale might be a little bit of a cheat as a new-to-me nature reserve as I have been there once before but that was rather a fleeting visit to look for autumnal fungi and anyway this is my second reserve for January! This time we planned an amble up the valley, looking out particularly for mosses and playing with the macro lenses on our matching cameras – our version of a girls’ day out!  We were glad to be in the sheltered valley amidst Saturday’s gales, even though the wind made it sound like jet planes were taking off through the trees above us.

Looking at the board at the entrance to the woodland, with its promise of Toothwort and Bird’s nest orchids, makes me want to return later in the season. The eastern part of the valley lies on millstone grit but, further upstream, the step-like bed of the beck shows it is flowing over limestone.  The limey soils here are home to some of those plants I want to come back and search for.

Deepdale Beck runs down to join the River Tees just west of Barnard Castle and part of the woodland through which it flows is owned and managed for conservation by botanist John Durkin.  It is semi-natural ancient woodland, managed by coppicing and thinning but with many very old trees and with plenty of dead wood left on the woodland floor to provide a habitat for fungi and invertebrates, not to mention the mosses we were looking for.

No doubt Deepdale has remained relatively untouched, despite its proximity to Barnard Castle, partly because of its steep valley sides and the speed and volume of the beck and its tributaries after rainfall. However what is now HMP Deerbolt, a young offender institution at Startforth, just above Deepdale, was the site of an army training camp until the 1960s so the valley was used for military exercises.  Military training does at least have the advantage of minimising other disturbance to wildlife-rich sites! 

The mosses we came in search of are everywhere, and particularly visible at this time of year when so little else is green.  I noticed this last year on my walks round Raisby Hill Grassland. Mosses rely on water for reproduction and lack proper roots and conducting tissue (xylem) to take up and transport water around the plant body.  Their leaves (technically phyllodes)  are usually only one cell thick and dry out very rapidly away from a damp, humid environment.  We see them most often in shady spots; in woodland, alongside flowing water and in poorly-drained grass. However, they also grown in exposed situations such as on the top of walls and at pavement edges.  Mosses can enter a state of suspended animation which allows them to survive severe drought, rehydrating when conditions improve.  When desiccated they are pale in colour and much less noticeable to most of us, hence their apparent abundance at this time of year.  Mosses growing in woodland also seem much less obvious in the summer – there is no point in them struggling to photosynthesise when most of the light is intercepted by the tree canopy above.  So, January is a good time of year to look at mosses, enjoy their beauty and, with help from more knowledgeable friends on Twitter and Facebook (you know who you are!) to begin to try and identify some. 

The first we found were two very common Feather-mosses on old tree trunks and dead wood stacked up near the path as we entered the dale.  Brachythecium rutabulum, Rough-stalked Feather-moss, has tiny spore-bearing capsules which look like nothing so much as miniature golf clubs to me.  Kindbergia praelonga, Common Feather-moss, suits its name much better to my eyes, with delicate pinnate shoots shown at their best when spreading across fresh tree bark.

Some of the other more readily distinguished mosses we found were living on damp soil – Plagiomnium undulatum goes by the rather clunky common name of Hart’s-tongue Thyme-moss but the long, undulate phyllodes do look very like its fern namesake. Thuidium tamariscinum, Common Tamarisk-moss, looks like a very different sort of fern, with its thrice-pinnate shoots (each ‘frond’ divided three times). Dicranum scoparium, or Broom Fork-moss, is different again, growing more as a cushion than the others, on both ground and trees.  Its long, elegant phyllodes float away from the stems as though water borne.

Five mosses seems like a reasonable tally for the day but we found a leafy liverwort too, Plagiochila asplenioides, growing on a dripping wall by the old rifle range.  Bryophyte cousins of the mosses, leafy liverworts look pretty similar but have pairs of phyllodes with a smaller one beneath, rather than the spiral arrangement round a stem more typical of mosses.

Of course it wasn’t all bryophytes – both dead wood and trees are covered in lichens such as Evernia prunastri, Cladonis fimbriata and the dramatic Peltigera praetextata as well as the more usual yellow Xanthoria.

There were many more fungal fruiting bodies around than we were expecting to see in mid-January too. Our first hint of this was masses of Scarlet elf cups peaking through the fallen leaves but there were bracket fungi and toadstools of various sorts growing on trees too, both dead and alive.  Sympathetic woodland management and a mild winter so far means there is plenty of food available for invertebrates and small animals and it was good to see bird and bat boxes on many trees.

We found evidence, too, of spring on its way in the shape of Cuckoo-pint, Butterbur and Dog’s mercury shoots and male Hazel catkins on the cusp of bursting open.  That has to be a good outcome for mental wellbeing on a cold, grey January day!

Last but not least, back to Barnard Castle for warming harissa roast vegetable and chickpea soup at Number 15, followed by a wander along to the Bowes Museum for another look at the Norman Cornish centenary exhibition – a grand day out!