Four botanists met at Watlington Hill (SU79) on a cold but bright morning last Sunday, 22
nd January, to explore the nearby Lower Deans Wood. The focus of the meeting was bryophytes, but vascular plants were also recorded. This is an account of what was found.
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| Berberis vulgaris found along the edge of Lower Deans Wood |
Lower Deans Wood is a small part of the extensive beech hangers on the steep Chiltern escarpment slope. These are rather grand, empty-looking places, but decent lists (given below) of vascular and lower plants were assembled over the course of a few hours (74 and 58 taxa, respectively). The first record of the day was of
Berberis vulgaris (barberry) at the edge of Lower Deans Wood: it is on the Oxfordshire draft Rare Plants Register and is an Oxfordshire first for SU79; it is known in the Bucks part of the hectad a few miles away in the churchyard in Turville.
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Frozen (and out of focus) Nowellia curvifolia on rotting wood with Lophocolea bidentata
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The woods did not give the appearance (to me at least) of being bryologically very exciting to begin with, with scraps of mosses on the bases of trees and the ground covered in a dense layer of beech leaves. However, as we got into the wood and conditions became steeper and more humid, things became much more inviting. Dead wood proved especially productive and the first notable find was the Atlantic liverwort and deadwood specialist
Nowellia curvifolia. Several other deadwood specialists were found, including the mosses
Aulacomnium androgynum, the nationally scarce
Herzogiella seligeri, and
Dicranum tauricum. Contrasting with
Nowellia, the latter three have a distinctly south-eastern bias in their distributions.
Where the ground was bare, the clay and exposed flints attracted much attention and proved interesting. Chief amongst the finds here was a little fruiting
Eurhynchium-like thing which Oli suggested might be
Oxyrrhynchium schleicheri. This it turned out to be. This is a relatively uncommon plant nationally, typically associated with sandy ground, but is known from across the Chilterns. On exposed flints were also found the tiny
Seligeria calycina and a nice little patch of
Trichostomum crispulum. There were also some beautiful colonies of
Plagiochila porelloides.
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Plagiochila porelloides
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The vascular plants were much as one would expect of a beech wood, i.e. very little. A few ‘ancient woodland indicators’ were present, e.g.
Galium odoratum (woodruff) and
Euphorbia amygdaloides (wood spurge), and there were some beautiful old cherry trees, one of my favourite features of the Chilterns landscape. Ferns were abundant in places, particularly along the top of the wood in Watlington Park where the soil appeared somewhat leached, with extensive stands of
Dryopteris borreri,
D. dilatata and
D. filix-mas. Members of the
D. affinis aggregate are fairly common in the Chilterns, and specimens of the segregate
D. borreri were interesting with what looked like two morphotypes present: the typical morph.
borreri and also morph.
robusta. The latter has rectangular dissections to the pinnules which have rather un-
borreri-like rounded and somewhat tapering ends. It has not been recorded in the county.
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| A rare find: fruiting Brachythecium glareosum. O.L. Pescott |
Also along the edge of the Park were some spectacularly mossy ash and sycamore trees, with great streaks of
Orthotrichum lyellii and
O. stramineum. We held out hope for
Leucodon sciuroides but nothing epiphytic of note was forthcoming. The ground proved a little more interesting, with
Brachythecium glareosum on exposed flint, and the calcifuges
Campylopus flexuosus,
C. pyriformis and
Ceratodon purpureus on churned-up earth.
B. glareosum even had sporophytes, a rare occurrence and seemingly a first record for the county.
The meeting concluded with a march back to the cars through Christmas Common, which accounts for most of the weeds on the list.
Sounds like a really positive expedition, with plenty of note-worthy bryological finds.
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