A management tool for monitoring the botanical condition of EWT grassland nature reserves
Sward structure: average height - this attribute is an early warning signal of the condition
that will be deleterious to plant assemblages of particular grassland types. Visually assess
the average height of the sward at intervals during the walk, i.e. the height of the main
mass of herbage.
TARGET: AVERAGE HEIGHT BETWEEN 5 - 15cm.
Sward structure: litter - the build up of dead plant material can signal problems due to
insufficient removal of biomass by grazing or cutting. Vascular plants are usually very
sparse and even limited appearance of dead material in a layer is likely to be noticeable
and signal a problem. Visually assess the cover of any litter layer at intervals during the
walk. Litter is dead plant material and is of concern where it forms a more or less continuous
layer made up of fallen stems and leaves.
TARGET: NO MORE THAN 25% OF THE SWARD.
Sward structure: bare ground - an important ecological role of small patches of bare
ground distributed through the sward is the provision of regeneration sites for seedlings.
This can be achieved through the treading of livestock. Mow ing alone in the absence of
grazing can lead to a reduction of species richness. However excessive trampling (poaching)
and over-grazing can increase bare ground to damaging levels. Bare ground must be visible
from above without disturbing the vegetation.
TARGET: NO MORE THAN 5%.
Assessment involves a simple structured walk, stopping at predetermined points and recording vari-
ous attributes. Sketch a route to follow on a map to cover the whole area. A W-shape walk is recom-
mended. The paces do not need to be even as the aim is merely to be more objective about where to
stop. Follow the route and at every stopping point search the area and record the various attributes
(Appendix 1). The size of the search area should be a full circle of approximately one metre radius.
At the end of the walk the frequencies of each attribute arc analysed to assign the grassland to
various categories. Only one category can be assigned to the grassland. The categories are as fol-
lows:
1) Botanically maintained: All desirable attributes are within targets.
2) Botanically declining: One or more desirable attributes are outside targets compared to the
previous visit.
3) Botanically recovered: All desirable attributes are now within targets but the feature was
declining on the previous visit.
4) Botanically recovering: One or more desirable attributes are outside targets but there is
evidence of recovery, i.e. one or more attributes arc now within targets compared to being
outside the targets on the previous visit.
Essex Naturalist (New Series) 20 (2003)
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