Pills, Pools and Marshes - Gower - page 248

FIG 142. Map of Llangennith Moors showing the pattern of ditches. (West Glamorgan Archive Service)
Owing to its varied agricultural past the present vegetation of the Moors is quite diverse. In the
southern part of the system there are agriculturally unimproved enclosures dominated by sedges Carex
spp., creeping bent Agrostis stolonifera and lesser spearwort Ranunculus flammula , together with marsh-
marigold and southern marsh-orchid. Elsewhere the former arable enclosures contain soft-rush and plants
suchasyellowirisandlady'ssmock Cardamine pratensis areabundant.Severalenclosureshavereverted
to marsh and these contain dense stands of soft-rush, meadowsweet and common reed.
ThefloraoftheditcheswhichdividetheenclosureswassurveyedindetailbytheCountrysideCouncil
for Wales in 1991. A wide variety of locally uncommon plants were found, including greater tussock-
sedge, spiked water-milfoil, mare's tail and unbranched bur-reed Sparganium emersum . In general the
ditches can be divided into two types, marshy ditches, which have very limited or no open water and
represent the final stages of the colonisation of the ditch by plants, and ditches where there is a signific-
ant amount of open water. Periodic cleaning of the ditches takes place to maintain their function as field
boundaries and this creates a range of plant communities across the marsh as a whole. While the initial
impression of the Moors is of a series of level fields separated by a network of narrow drainage ditches,
closer inspection reveals a substantial main drain which runs westward through the system before it exits
through the sand dunes at Diles Lake on Rhossili beach. The upper section of this drain has a diverse ve-
getation more typical of riversides, including meadowsweet and Indian, or Himalayan, balsam Impatiens
glandulifera , which was introduced to British gardens in 1839 and has since become widely naturalised.
The marshy ditches have a similar flora to some of the less improved enclosures, being dominated
by tall emergent species such as soft-rush, yellow iris, branched bur-reed Sparganium erectum , together
with Yorkshire-fog and creeping bent, but prickly lettuce Lactuca serriola , common centaury and yellow
loosestrifearealsofound.Ditcheswithlargeamountsofopenwatercontainaquaticspeciessuchaswater-
plantain Alisma plantago-aquatica ,fool'swater-cress Apium nodiflorum ,lesserwater-parsnip,water-star-