Botanical Indicators of Possibly Interesting Grassland

Botanical indicators of potentially interesting grassland- especially old meadows and pastures

These are generally sites rich in plant species (particularly flowers other than grasses). If they also include marshy areas then they are likely to be of very high natural history interest (and nature conservation value).

Short exercise in your own time

Important factors in maintaining unimproved meadows and pastures are lack of recentploughing, continued use of traditional grazing or mowing regimes, and lack of inorganic fertilizer or herbicide application. In the case of wet meadows, a lack of drainage improvement is critical.

Grasslands are very variable plant communities that often occur in relatively small, discreet blocks. Variability may be linked to environmental factors (soil pH, soil nutrient status, soil moisture, latitude, altitude, aspect, geology etc) and land-use or history of land-use and management.

For grasslands, indicator species are normally used for the following:

1. To identify sites with interesting or rare plants. These may be particularly species-rich communities and may not necessarily include rarities.

1. To identify sites with relatively undisturbed ‘unimproved’ communities and a continuity of grassland vegetation on a site.
2. To identify particular plant communities which may be of interest e.g. wet meadows, acidic grassland, and calcareous grassland.

These three main objectives may coincide on a site and are often interrelated e.g.:

Old, unimproved, species-rich, calcareous grassland

Usually, species-richness and the occurrence of rarities or locally distributed species do coincide with lack of improvement and ‘ancientness’ of the community. This needs to be viewed with caution.

The use of Indicator Species

Species occurrence and status at a site needs to be viewed in the context of:-

1. Associated species

1. Known environmental factors – geography, geology, soil, topography, aspect etc

1. Known history of the site and its management

1. The understood status of the particular species in the district and in sites with similar environmental factors and constraint.

The attached lists are not considered definite or necessarily reliable. They are an attempt to draw together particular ideas and information into a relatively usable and coherent form. The main types of indicators listed are:-

Species believed to be reliable indicators of relatively undisturbed sites. (1) (Many sites that may appear now to have been undisturbed for many years may not actually be so. BEWARE!)

Species that by their presence may draw your attention to a site that may prove to be good. These are plants that often occur in old or species-rich communities but are by no means faithful to them. These same species may occur in other environments habitats and in relatively disturbed areas.(5)

Species that by their presence give information about the environmental conditions at a site. (2,3,4).

• INDICATORS OF POORLY DRAINED AREAS (2)
• INDICATORS OF ACIDIC SITES (3)
• INDICATORS OF CALCAREOUS SITES (4)

Key:

1. Good indicators of old, unimproved grassland,
2. Indicators of poorly drained sites
3. Indicators of acidic sites
4. Indicators of calcareous sites
5. Characteristic members of the plant communities of species-rich grassland:

(The actual species mix varies from site to site depending on individual site characteristics and also within a site depending on localized conditions).

( ): indicates a degree of doubt as to the reliability of this character.

Generally good indicators of relatively interesting and possibly undisturbed sites

Comments

Forbes

esp. north facing slopes

[Based on an original and provisional list by Dr Ian D. Rotherham, SheffieldCity Ecology Unit, and Mr Gerry Firkins, Sorby Natural History Society, for conservation assessment in the Sheffield Area. November 1987]