Wiltshire: the Shalbourne Stream

27 July 2017 (Half day)

This walk follows the Shalbourne stream half way from its source to Hungerford  (one can walk all the way, but in the latter half the path is mostly some way from the river).  Although there is no great botanical diversity, the walk does visit two rare native plants.

          We started at the roadside at the south end of Shalbourne village (SU310628).  The path goes north beside what at this time was no more than a narrow sunken damp river bed.  In the shade of the trees were Hart's-tongue Fern Asplenium scolopendrium and Gooseberry Ribes uva-crispa.  Level with the centre of the village to the east the stream widened and there was some water, at the site of old watercress-beds, although the only Watercress here now was Fool's Apium nodiflorum.

The watercress beds are now just fool's watercress

Shortly after this we were separated from the river itself by a field hedgerow.  The arable land had no plants of interest (mostly Fool's Parsley Aethusa cynapium) but there was a single clump of Wild Basil Clinopodium vulgare by the hedge.  The stream from this point to the north end of the village has been widened into small lakes in parts, part of the extensive garden of Mill House.  One of our target plants grows in and beside the river in these grounds - Green Figwort Scrophularia umbrosa, although it can also be seen later in the walk.  The owner allowed us access to the garden and we counted four clumps of the plant.  It is closely related to water figwort Scrophularia auriculata (which we did not see at all by this stream).  It is best told by the bright green colour of the leaves and stems and the sharply toothed leaves which narrow to the winged stalk (water figwort tends to purplish and has blunt teeth on the leaves, which are somewhat rounded at the base).  We also thought the inflorescences were more crowded and the flowers smaller, while the whole plant tended to be floppy, the stems, although stout, often procumbent, whereas water figwort is usually a very upright plant.  The stems are widely winged, but water figwort sometimes also has wings virtually as wide.  The books detail differences in the flowers too, but these can be difficult to use.  The flowers were said to be darker purple, but the ones we saw were all reddish purple and very much like water figwort.  The staminode is cleft, but this is only occasionally clear, as it is often distorted and soon begins to shrivel.  The calyx-lobes are said to have a wider white edge which is more serrate, but the margins soon turn brown and they did not appear to be noticeably wider than those of water figwort, while they were better described as "ragged" than serrate.  Despite these issues the overall appearance, even from a distance, had a clear jizz that immediately separated it from its congener.

Green figwort, Shalbourne stream

From Mill House northwards the stream, although it remains shallow and clear with a stony bottom, has thick bank-side vegetation, mainly of Wild Angelica Angelica sylvestris, Meadowsweet Filipendula ulmaria, Square-stemmed StJohn's-wort Hypericum tetrapterum, Guelder Rose Viburnum opulus, Gipsywort Lycopus europaeus, Water Mint Mentha aquatica, native Common Comfrey Symphytum officinale and Hop Humulus lupulus.

Shalbourne stream just north of A338

Wild angelica

Square-stemmed StJohn's-wort

The path does not continue by the stream when you reach the road by Mill House and you have to descend the road a short way to the 13thC Church to take a footpath going east into another going north to regain the stream.  While in Shalbourne we noticed that roadsides included introduced species such as Hungarian Mullein Verbascum speciosum, Japanese Anemone Anemone x hybrida, and Sowbread Cyclamen hederifolium. 

Hungarian mullein

Japanese anemone

Cottage, Shalbourne

Shalbourne Church of St Michael an d All Angels

We had only regained the stream a short while before reaching the A338 road, which has very fast-moving traffic.  The stream passes under the road, but we had to divert left a short way to where the footpath continues beside a farm, soon returning, however, to the stream.  By the road there was a large colony of Horseradish Armoria rusticana and a little Hedgerow Cranesbill Geranium pyrenaicum.  There was also a prominent clump of Common Poppy Papaver rhoeas at the edge of a bean crop.

From here runs the best stretch of the stream, although we seldom got a close view of it because of the wide band of vegetation including much Nettle Urtica dioica.  We saw a small clump of Green Figwort at SU3177964369, and also a small patch of what was probably Blunt-fruited Water-starwort Callitriche obtusangula, although there were no fruits to confirm.  The best and most accessible patch of Green Figwort occurred where the stream went under the paved track to Eastcourt Farm (SU3183164501).  Here there was a great deal of the plant, some of it having had to be cut down because it was so rampant.

          Across the track the path continues away from the river beside woodland, although it would be possible to walk on further by the water.  We did not follow the stream further here, however (so there may be more Green Figwort further north) but walked beside the wood (Westcott Copse), which is notable for its large population (thousands) of Spiked Star-of-Bethlehem Ornithogalum pyrenaicum (or Bath Asparagus as it is often known).  The narrow-petalled greenish-white flowers were unfortunately well gone over, but the tall spikes of fruits were very evident, even at the edge of the wood, rising starkly (the leaves having now all withered away) through the brambles and other vegetation.  It is a shame that one cannot time the walk to see both this and the figwort at their best, but the latter would not be very evident in June when the former would be in flower.

Spiked Star-of-Bethlehem in flower (photo taken at Kew)

Fruiting spike, Westcott Copse

From here we retraced our steps to Shalbourne.  (The Plough pub there does lunches and has a good reputation.)