North West Sussex, just north of the South Downs, has an area of lowland Wealden greensand heathlands (all called commons). These heaths contain some interesting and rare plants including parasitic Dodder and the insectivorous Round-Leaved Honeydew; and many other fascinating flowering plants, lichens and bryophytes associated with heathlands. This post focusses on Sundew and Dodder, but also includes some images of Greensand Heath flowering plants, such as the beautiful Bog Asphodel, and bryophytes, particular bog mosses, and heathland lichens at Lavington Common. I saw Dodder (parasitic) and Round-leaved Sundew (insectivorous) at Hesworth Common, in Fittleworth, and Round-leaved Sundew at Lavington Common
To get to Fittleworth, for Hesworth Common, I caught the 1 bus to Midhurst 1 Bus Route & Timetable: Worthing - Midhurst | Stagecoach (stagecoachbus.com) from Worthing and got off at School Lane stop Fittleworth; it is a 10 minute walk to Hesworth Common from the bus stop. (The bus runs once an hour from Worthing and is a 63 minute journey to Fittleworth). To get to Worthing I took the train from Brighton.
All sections of text in italics are quotations, sources sited.
The photographs in this post are presented chronologically (in the order in which I saw things)
I am only an amateur naturalist; thus all identifications are provisional; if you note a mistake in identification please feel free to tell me. If you want to contact me about any aspect of this blog, email me at simeon[underscore]elliott[at]gmail[dot]com.
After visiting Hesworth Common, I walked on to Lavington Common, National Trust Lavington Common | Sussex | National Trust along the Serpent Trail Explore the Serpent Trail - South Downs National Park Authority through Coats Common, Sutton Common, Burton and Chingford Ponds, and Dunston Common. This is about a 10 mile walk i.e. all of stage 8 of the Serpent Trail and a quarter of stage 9. To get home, I then walked from Lavington through part of Graffham Common and Selham to the Halfway Bridge bus stop on the Midhurst to Petworth road and got the 1 bus back to Worthing (and then a train to Brighton); see Heyshott, Ambersham & Graffam Commons; Sussex Lowland Heath and Climate Change. 10.07.23 for details. But this is another 3 miles, making the whole walk 13 miles. You can see Dodder, Round-leaved Sundew, as well as Bog Asphodel, Cross-leaved Heath, Bell Heather, Purple Moor Grass, and lots of great plants, lichens and bryophytes just by walking round Hesworth Common
Theses heaths are on the Folkestone Beds of the Lower Greensand. t=This is an area very different to the South Downs chalk downland and the High Weald ghyll woodland of Sussex; these heaths are geologically, biologically and historically fascinating. The Serpent Trail is the long distance path linking these heathlands, see South Downs Walks: The Serpent Trail. See Heyshott, Ambersham & Graffam Commons; Sussex Lowland Heath and Climate Change. 10.07.23 for Heyshott, Ambersham, and Graffham Commons; this post deals with just Hesworth Common & Lavington Common. For the Commons west of Midhurst see Butterflies & Birds; Drought & Reduced Abundance. Iping & Stedham Commons.16.06.23
The majority of the Wealden Greensand landscape character area lies within the boundaries of the South Downs National Park. It is essentially a medieval landscape with a small scale, intimate and mysterious character which is in striking contrast to the openness of the rolling chalk hills of the neighbouring South Downs. Its varied and complex landscape is comprised of a combination of clays, sand and sandstones which have produced an undulating topography of scarp and dip slopes, well wooded with ancient mixed woodland of oak, ash, hazel, field maple and birch. Distinctive steep woodland hangers, open heathland vibrantly coloured in summer, small pastures, irregular fields defined by hedgerows, low ridges and narrow vales drained by streams and rivers are all distinctive features of this character area. It is a popular area for horse breeding with a number of stud farms breeding polo ponies and thoroughbreds. Many narrow winding lanes are distinctively deeply sunken lined with trees whose exposed twisting roots grip chunks of sandstone. These lanes evolved before road surfacing and were eroded through the ages by weathering and the passage of foot, hoof and trotter as farmers drove their pigs up to the High Weald’s woodlands to feed them on the abundance of acorns (examples of transhumance and the practice of pannage). To the north there are dramatic views from the top of the wooded sandstone ridges. These ridges rise steeply from the Rother Valley and drop away in a dramatic curved escarpment that is deeply carved by stream valleys
The guide to the Serpent Trail lists Sundew as a trail-wide plant and says of Sundew: Tiny insectivorous plants that use sticky dew drops secreted from their hairy leaves to trap insects that land on them. The round leaves slowly curl around the insect, digesting the prey. Absorbing these nutrients helps sundews to survive on the nutrient-poor heathland soil. Typically found on wetter areas of the heath, the dew was once collected by people for use as an anti-aging cream! When: June to August South Downs Walks: The Serpent Trail.
Francis Roses lists Round-Leaved Sundew and Oblong-leaved Sundew, as being common on the wet parts of West Sussex's heathlands (in the Habitats and Vegetation of Sussex, 1991. p.10). Of the heaths I have visited - Trotton, Iping, Stedham, Midhurst, Heyshott, Ambersham, Graffham, Lavington, Coats, Sutton, Dunston, Hesworth and Fittleworth (both Hesworth and Fittleworth Commons are in Fittlewort) - only Lavington and Hesworth had visible Sundews and only Round-Leaved Sundews.
13.07.11 Hesworth Common, Fittleworth
The Sundews I saw were in the lower part of the common where there is a small bog. Bogs on Greensand Heath occur where the greensand sits on clays allowing for a build up of water. The Sundews were mostly around the edge of the water, growing wiyh sphagnum mosses
The bog in which the Sundew were growing
17.07.21 Hesworth, Common Fittleworth
From Chris Thorogood excellent book Weird Plants, Royal Botanic Gardens Kew, (2020) .52
SUNDEW
Living flypaper
Drosera spp.
The sundews are a large group of carnivorous plants that occur on every continent except Antarctica. They typically inhabit acidic and nutrient-poor fens and bogs, and supplement their diet with small insects. Sundews range from a few centimetres across to over a metre in height. All species produce leaves with numerous glandular tentacles, which secrete a sweet mucilage to attract and ensnare insect prey. Insects that land on the leaves stimulate the sticky tentacles to bend inwards. Upon struggling to escape, the insects become exhausted and are asphyxiated by the tentacles' sticky mucilage. The insects are partially dissolved by digestive enzymes, and the nutrients subsequently released are then absorbed by the plant.
17.07.23 Lavington Common
Sundews with their small white flowers with Sphagnum mosses probably Sphagnum denticulatum. At Lavington the Sundews were costly confined to a small area of the commons where bogs abutted the paths. The Sundews were mostly in linear depressions in the bogland.
A Sundew digesting an insect probably a mining bee.
Entry in Sussex Botanical Recording Society (2018) The Flora of Sussex, p.210, for Sundew
Droseraceae - Sundew family
Drosera rotundifolia L. Round-leaved Sundew
Native. Sx: scarce, very locally frequent. Bog and wet heath. On acid soils among Sphagnum, by bog pools, and on open damp ground. Said by W-Dod (1937) to be rather common and locally plentiful, it had declined by the 1970s.
Since then it has decreased further. However, as the map shows, it is still locally frequent on the Lower Greensand in the NW of WSx and on Ashdown Forest ESK with an outlying station on Chailey Common (TQ32Q). Some wet heath and bog was lost to forestry and agricultural drainage during the 20th century, but another major cause of habitat loss has been the cessation of grazing by livestock on heathland. Cattle and horses grazed down vegetation and created areas of poached ground, and without them open wet areas became subbed up, drier, and more vulnerable to severe fires. On some wet heaths disappeared or became confined to vehicle ruts and tracks. In recent years conservation bodies have re-introduced grazing on some heathland reserves and created wet scrapes. On Blackdown (SU93A) Drosera had not been seen for any years but was re-found in 2007 after the National Trust restored cattle grazing. On Stedham Common it has increased greatly following renewed grazing and the digging of scrapes (SU82K), and in Monkmead Wood at West Chiltington it has benefitted from scrub clearance and scrapes (TQ01T). It has preserved on Wheatsheaf Common by the mowing of the golf course Sin several of the places where it survives, such as Hurston Warren (TQ01T) and a number of locations on Ashdown Forest, it still occurs in good quantity.
Dodder, Hesworth Common
At Hesworth Common, I also saw Dodder; which grows on other plants, at Hesworth .mostly on Bell Heather, Erica cinerea and Common Heather, Calluna vulgaris.
From Chris Thorogood (2020) Weird Plants, Royal Botanic Gardens Kew, p. 34
DODDER
Vampire lasso
Cuscuta spp.
Dodder, also known as strangle-weed and witch's hair, not only steals from other plants, it lassoes and strangles them. When dodder seeds germinate they must find a suitable host plant within a few days or they will perish. Upon encountering a preferred host plant, they wrap their stems around it in a way similar to bindweed (Convolvulus spp.) which, indeed, is a relative of the dodder. They then penetrate the stem of their host, from which they extract water and nutrients. By the end of the growing season, these parasites can completely smother their hosts in great mounds several metres across. Some tropical species are so vigorous, they even reach the tree canopy. Found throughout the temperate and tropical world, like the broomrapes, some dodders are a severe constraint to crop cultivation.
Entry in Sussex Botanical Recording Society (2018) The Flora of Sussex, p.238
C. epithymum (L.) L. Dodder
Native. WSx: occasional, local; ESx: scarce. RDL: Vulnerable. Heathland; chalk grassland and cliffs. Described as frequent by W-Dod (1937) but only occasional by Hall (1980). A number of earlier records were from clover fields, where it was recorded as C. trifolii. Most recent records are from heathland, where the host is usually Calluna vulgaris, Erica cinerea or Ulex. Rich et al. (1996) quotes from an 1885 article by E. Webb which says that on Ashdown Forest it occurred on 15 different hosts, including 'oak, hawthorn, agrimony, gorse, needlewhin, heath, ling, wax-heath, Blechnum fern, both on barren and fertile fronds, and bracken. Rich also found it on other species on the Forest, including Pedicularis sylvatica, which is itself a semi-parasite. There are good populations on some of the heaths on the Lower Greensand in WSX, such as Iping Common (SU82K & L). It is now scarce on chalk, where the most frequent hosts are Thymus, Trifolium and Medicago. However, RBL studied the host plants of a small colony on Levin Down and found parasitic suckers attached to 22 different species, including Achillea millefolium, Galium verum, Ranunculus bulbosus and Rosa rubiginosa (SU81W). The largest population on chalk may be on the verge of the A29 on Bury Hill, where in some years it covers many square metres (TQ01B).
Other interesting flowering plants - and bryophytes and lichen - at Hesworth and Lavington Commons
Hesworth Common
Big Asphodel
The Latin name of bog asphodel, ossifragum, literally translates as 'bone-breaker'. This unassuming plant acquired this violent name because it was believed that the livestock that grazed on it got brittle bones. However, it was actually the calcium-poor pastures that caused the problem.
The sulphur-yellow, star-like flowers of bog asphodel brighten up our browny-green peat bogs, damp heaths and moors in early summer. Borne on spikes, the flowers appear from June to August, and as they fruit in autumn, the plants turn deep orange, continuing to colour the bogs. Bog asphodel produces creeping rhizomes (underground stems) from which it can reproduce; however, it also produces seeds and its flowers attract a range of pollinating insects. Bog asphodel | The Wildlife Trusts
The bog at Hesworth where the Bog Asphodel and Sundews grow
Lichens at Hesworth
Many of the oaks and beeches at Hesworth were dripping with lichens; mostly common lichens, but they are magnificent sights
Evernia prunastri, Oak Moss and Flavoparmelia caperata, Common Greenshield Lichen
Ramalina Farinacea, Farinose Cartlidge Lichen and Flavoparmelia caperata, Common Greenshield Lichen
Lavington Common
A beautiful miniature landscape: Campylopus introflexus (moss), Amanita fulva (fungus), Erica tetralix & Caluna vulgaris (heathers), & Cladonia ciliata (lichen).
Theses three heathers - Common, Bell and Cross0Leaved Heath - were common on all the Sussex lowland heaths
Cross Leaved Heath, Erica tetralix, Typical of wet heathland
Common Heather, Calluna vulgaris,
Bell Heather, Erica cinerea
Lichen carpets - the direr areas of the lowland heaths often have carpets of Cladonia sp. lichens, mostly the "reindeer lichens" Cladonia rangiferina and C. portentose
