Ramsons carpets

Two recent woodland trips provided the inspiration for this post on ramsons (Alium ursinum). The first trip was an afternoon recce for some uncommon woodland flora when a visually compelling ramsons carpet was chanced upon in less than ideal lighting. Another location identified and added to the seemingly ever lengthening 'to visit under more idealised lighting' list.

To increase the chances of finding ramsons carpets an appreciation of their ecology is useful and a Hungarian research paper provides some useful insight into the habitat requirements amongst other things:

"In spite of its broad distribution across continents, and its occurrence as a weed, the species cannot be considered as a generalist. Several authors have classified it as a habitat specialist, having a rather narrow range of ecological tolerance (Grime et al. 1988, Kevey 1977, Rychnovská and Bednář 1998). A. ursinum is particularly sensitive to the availability of water. It requires a mesic soil, which is well-drained. Both drought and waterlogging are unfavourable (Csiky et al. 1999, Grime et al. 1988, Kevey 1977, Rychnovská and Bednář 1998, Trémolières et al. 2009, Tutin 1957). Sufficient humidity in the air is also crucial for survival (Kevey 1977, Kovács 2007)."

"The species strongly prefers the forest floor; it can rarely be found outside of a forest (Grime et al. 1988), only in some places with high, evenly distributed precipitation (Tutin 1957) or along rivers or streams (Kevey 1977)." 

"The plant requires a nutrient-rich soil (Tutin 1957)"

"A. ursinum is sensitive to the pH, missing from base-poor sands and mor soils (Tutin 1957). Falkengren-Grerup and Tyler (1993) demonstrated experimentally that mor (pH 3.6) inhibited the production of new roots. Tutin (1957) estimated the tolerated pH range from 5.5 to 7.9; Grime et al. (1988) narrowed it to 6–7.5" 

Extracts taken from Oborny, B., Botta-Dukat, Z., Rudolf, K. and Morschhauser, T., 2011. Population ecology of Allium ursinum, a space-monopolizing clonal plant. Acta Botanica Hungarica, 53(3-4), pp.371-388.

Ransoms are an indicator species of ancient woodland and some online detective work cross referencing national ancient woodland inventories e.g. Wales and England, against a relevant geology map will identify candidate sites of ancient woodland overlying calcareous bedrock. It is then a case of recceing the candidate woods.

The second trip was one made specifically to photograph a riparian carpet of ramsons within the Lower Wye Valley AONB on a rare day with overcast skies, the weather in May, thus far, has been mostly clear blue skies and sunshine. The woodland is designated as ancient semi natural and has outsize coppice stools of alder, ash, wych elm and hazel with a ground flora community of ancient woodland indicator species.

4 spring woodlands

May 2016, thus far, has turned out to be a vintage one for photography in my local woods : the weather has contributed with low wind and rain to bring out the colours. Locations ground-truthed back in the winter have provided some photographic reward and also some old haunts revisited.

Starting with a rewarding trip to a by now familiar scowles woodland for dawn, as the sun rose into a strip of clear sky on the horizon with rainclouds covering the remaining 99% of the sky, the resulting light was good, but all too brief.

With sunrise over, I headed onto another woodland where wildflowers in some parts of the wood pick out the underlying geology and also archaeology, the better drained soil of mineral spoil from bell pits and anomalous earthworks form a preferential habitat for bluebells and wood anemones.  This particular wood is planted semi natural ancient woodland and deserving of a future post of its own, as there is a complex interaction of ground flora with underlying sandstones and limestones, past management and mineral workings.

Bluebells pick out a bell pit in beech and ash woodland

Making a photograph of ground flora corresponding to underlying geology and archaeology is challenging, happily there are also the are views of spring woodland. The primary colours of green and blue, I find visually appealing, especially when saplings and suckers add to the field layer and break up the tree trunks.

I have been photographing the local woodlands for over a decade and was finally rewarded with a forecast of fog, steady rain and light winds in spring. After some thought I decided on a wood that I have struggled to do justice to in the past, as the woodland grows on an escarpment. Escarpments generally denote more competent geology and there is a history of quarrying quartz conglomerate for grinding stones. The woodland is a mixture of singled coppice, derelict coppice and timber trees all broadleaf with the exception of a few yew and holly trees. The ground flora is slowly recovering, benefiting from a harvesting operation a few years ago and along with some windthrow has opened up the canopy. Woodlands dominated by mature beech can be sterile affairs for ground flora.

Some of the rocks littering the slopes result from quarrying activities, others I am not so sure and could well envisage an origin from periglacial mass movement.

The last wood to report on has an extensive carpet of ramsons growing over scowles and in another area large hazel coppice stools with a more diverse ground flora. The Forestry Commission spray paint was also prominent with a number of beech and ash trees marked for harvesting and thinning.

A few evening woodland visits have been unproductive due to harsh lighting and/or wind motion of the subject, nonetheless the four visits with favourable weather, helped mitigate against the poor weather that marred the photographic ambitions of spring of 2015.