A management tool for monitoring the botanical condition of EWT grassland nature reserves
addition, the data recorded must be of a consistently high quality. Recording various attributes of
grasslands will allow a better overall assessment of the current status and future trends. These are: a)
extent of interesting types of grassland; b) sward composition; and c) sward structure. Sward
composition can be divided into positive and negative 'indicator' species and grass/herb ratio.
However, the 'indicators' must: a) be easy to identify; b) reflect positive and negative management
rather than other factors, such as weather or life strategies; c) be easy to record in a repeatable way;
and d) be standardised to ensure continuity between years and samplers. The presence of particular
species forms a critical part of the assessment and visits have to be made when these species arc
easily identifiable. Sward structure can be broken down into sward height, cover of litter and extent
of bare ground.
Essex Wildlife Trust volunteers triallcd the grassland monitoring system over the summer and their
comments have been incorporated in tins document.
Method
Ideally grasslands should be visited annually. However the frequency has to be considered within
the framework of available staff and volunteer resources. At best an annual visit is desirable although
a minimum of one visit in a 3-year period may be more realistic. The priority is to ensure grasslands
are managed and maintained to a predetermined condition. Management is vital to the conservation
of grasslands and the speed at which grasslands can change is such that where possible more frequent
visits should be made.
Grasslands should be assigned various targets bearing in mind their conservational objective. The
various attributes with suggested targets include:
1) Extent - the extent of the wildlife interest feature being assessed.
TARGET: NO LOSS OF AREA
Sward composition: grass/herb ratio - this attribute refers to the proportion expressed
as a percentage cover of non-Poaceae (grasses) in the sward. This includes most species
although a recent report suggests that competitive herbs were sometimes recorded in high
proportions (Robertson et al. 2002). Visually estimate the proportion (%) of herb cover in
the grassland. Herbs include all vascular plants except grasses, i.e. rushes and sedges are
'honorary' herbs. Estimate by looking down on the sward at stops rather than looking
across the top of it. Patchiness should be averaged out.
TARGET: 40-90% HERBS
Sward composition: frequency of positive indicator species/taxa - this attribute is of
key importance in assessing condition as it reflects the ecological condition and survival
of particular assemblages of grassland species. The selection of species was based on a)
species largely confined to unimproved grassland and not normally found in improved or
semi-improved grasslands, b) species characteristic of and reasonably frequent in the
grassland type, and c) species relatively easy to identify and are present and obvious in the
sward for a reasonable length of time. The following species were selected as positive
Essex Naturalist (New Series) 20 (2003)
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