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layer. The front bucket of a JCB-lype digger was used and so die plots were uneven, with
gravels and mineral soil being exposed in some places and little ridges being left in others.
The area scraped in April 1992 was the main area studied (see Plate 8). Prior to soil-stripping
work the plot was dominated by Purple Moor-grass with several large stumps of Birch. Two
clumps of mature Heather (Calluna vulgaris) were mapped although they had been completely
destroyed above ground by fire prior to the commencement of the work. When die plot was
scraped the Birch stumps were pulled up, including the roots, but the Heather clumps and small
patches of the surrounding leaf litter were left as islands. These areas were not included in the
quadrats that were examined in 1993 and 1999 (see Table 2 below).
An area of 1.6 hectares encompassing the three trial scrapes was then fenced in late 1994 to
allow grazing the following year on an initial trial period of four years until 1998 when it was to
be reviewed. The grazing has been achieved using English Longhorn cattle, a traditional breed
(see Fig. 2) which is able to deal with rough and nutrient poor vegetation. The dates of grazing
and the numbers of cattle involved are given below in Table 1. Surveys were carried out
between 1994 and 1998 to assess the impact of grazing.
Table 1 Timing of grazing and grazing pressure at Long Running (1.6ha)
Start date Finish date No. of cattle Animal weeks per
___________________________________________________________hectare per year
29/04/95 September 95 4 cows; 39
(removed for 3 2 cows (after August) approx
weeks in August)_____________________________________________________________
First week May 96 September 96 2 cows 23
_________________________________________________________________approx______
23/05/97 September 1997 2 cows 20
(calf present for some
_______________________________________of period)_____________________________
21/05/98_____________31/07/98____________2 cows_____________________12.5_______
17/05/99_____________19/07/99____________2 cows_____________________11.25_______
The sections below present details of the monitoring of the trial soil-stripped plots and of the
separate monitoring of the grazing on the surrounding unstripped heathland.
Monitoring methods
To examine the effect of the mechanical soil-stripping, a survey of the whole April 1992 plot,
divided into 45 3 x 3 metre quadrats, was carried out. The quadrats covered only those areas
where the turf and soil had been stripped (see above). The first survey was conducted in May
1993 a year after the scrape had been created but before grazing had commenced. A follow-up
survey, using the same 45 quadrat divisions, was repeated in June 1999 during the 5th season of
grazing.
To monitor the impact of grazing on the unshipped heath vegetation two 50 x 50 metre grids
were established, one in a bracken-dominatcd patch ('the southern grid') and the second
covering
Essex Naturalist (New Series) 16 (1999)