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a Purple Moor-grass-dominaled area ('the northern grid'). The baselines for the grids were
marked out by buried metal markers and re-located each year with the use of a metal detector.
Grid lines were then laid out at 90° to these baselines using compass bearings, measuring tapes
and ranging poles. Within these 0.25 hectare grids 30 random l x l metre quadrats were
surveyed out of the possible 2500 (1.2 % coverage) in 1994. prior to grazing, and then
subsequently in 1995 and 1998. The surveys were carried out in the autumn after the Heather
had set seed.
Within the 30 random quadrats surveyed annually the following were recorded:
presence/absence of plant species; number and height of Bracken stems; number and height of
Purple Moor-grass tussocks; and percentage cover of any plant species rooted within the quadrat
and covering more than 5% of the area when viewed from above.
Results
Soil-stripped scrapes
After one year all three 25 x 25 metre scraped areas contained germinated Heather, as well as
sedges and rushes, and Cross-leaved Heath germinated in the second year in the southernmost
scrape created in August 1992 (Dagley 1996). There were significant differences between the
three scrapes with the August 1992 plot containing the only Cross-leaved Heath and by far the
greatest density of Heather. Tormentil (Potentilla erecta) and Heath Rush (Juncus squarrosus)
regeneration. The August 1992 plot does not flood in the winter as the April 1992 and
December 1991 scrapes do and this could explain the better results with Heather, although
perhaps not with Cross-leaved Heath.
The whole April 1992 plot was recorded in detail, dividing it up into 45 3 x 3 metre quadrats.
Heather germinated in June 1992 and one year later in 1993 the area was much more diverse
than the surrounding heathland with 16 species of liigher plants occurring in more than 5% of
quadrats (Dagley 1996). Common Yellow Sedge (Carex viridula ssp. oedocarpa) previously
considered extinct was recorded from 15% of quadrats, Tormentil and Heath Rush from 31%
and Heather from 40% (see Table 2).
Examination of the same 45 quadrats in June 1999 revealed significant increases in 5 plant
species, including Heather (see Table 2). Heather has increased its cover to 62% of quadrats,
despite the winter flooding over part of the plot, and Common Yellow Sedge has increased to
22% frequency. Wavy Hair-grass (Deschampsia flexuosa) has begun to assert itself a lot more
(27% of quadrats) and this may well be a response to the grazing pressure as Wavy Hair-grass is
not particularly palatable whereas Purple Moor-grass has been grazed hard (see grazing results
below).
Three plant species have undergone dramatic increases. Heath Rush now covers more or less the
entire area (96%), although a proportion of it is grazed and prevented from setting seed each
year. Mat Grass (Nardus stricta) and Green-ribbed Sedge (Carex binervis), which had not
appeared by 1993, now occur in 38% and 49% of quadrats respectively. Green-ribbed Sedge,
widespread across the higher parts of the Forest, had occurred in low frequency across the heath
prior to the scraping and grazing but has flourished since the work began. The Long Running
population now constitutes the greatest concentration in the Forest and probably in Essex for
this uncommon species. Mat Grass had not been recorded in recent years from this particular
area of Long Running, although it has been recorded for the site as a whole (Jermyn 1974) and it
occurs commonly in the Forest's drier heaths and acid grasslands.
Essex Naturalist (New Series) 16 (1999)