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General Description:

This habitat category includes both areas of herbaceous vegetation dominated by grasses and certain wet communities dominated by Juncus species, Carex species, Filipendula ulmaria or by other marsh herbs. For grasslands where there is a greater than 25% cover of dwarf shrub heaths these are referrable as 'heathland', for emergent stands of tall reed-grasses, see swamp, for coastal grasslands, see saltmarsh, dune and maritime cliff and slope.

Most grasslands have been subjected to some degree of agricultural improvement by repeated grazing, mowing, fertilising, drainage or herbicide treatment. It is important to try to distinguish unimproved and semi-improved from improved grasslands. However, these grassland types form a continuum, so that it is not possible to define each with precision, especially as species critical for their definition are often only observable for a short season in the year. Agricultural improvement usually results in a decrease in the floristic diversity of the sward and dominance by a few quick- growing grasses such as Lolium perene, Holcus lanatus and Festuca rubra. The resulting sward composition is likely to vary with intensity of treatment and with the composition of the original sward, so careful field training is necessary to define and maintain the boundaries between these categories. However, residual difficulties are bound to occur.

Grassy roadside verges, railway cuttings and embankments may be very important features, especially in intensively farmed areas. If they are wide enough they should be mapped as the appropriate grassland habitat. Narrow herb-rich verges should be shown by a broken orange line and target noted, if time permits. See also amenity grassland (J1.2).  

Unimproved grassland:Unimproved grasslands are likely to be rare, especially in the lowlands. They may be rank and neglected, mown or grazed. They may have been treated with low levels of farmland manure, but should not have had sufficient applications of fertiliser or herbicide, or have been so intensively grazed or drained. As to alter the sward composition significantly. Species diversity is often high, with species characteristic of the area and the soils and with a very high percentage of agricultural species.In cases of doubt, map as semi-improved and target note the need for further information.

Semi-improved grassland:Semi-improved grassland is a transition category made up of grasslands which have been modified by artificial fertilisers, slurry, intensive grazing, herbicides or drainage, and consequently have a range of species which is less diverse and natural than unimproved grasslands. Such grasslands are still of some conservation value. Semi-improved grassland may originate from partial improvement of acid, neutral or calcareous grassland and should be mapped as such. However, it should be noted that improvement reduces the acid or calcareous character of the grassland, so that this is not always easy to distinguish in the field.Species diversity will generally be lower than in unimproved grassland in the same area. If the signs of improvement listed under B4 are lacking, the grassland is likely to be semi-improved and should be mapped accordingly.

B1 Acid grassland:

Acid Grassland Description: Grassland in this category is often unenclosed, as on hill-grazing land, and occurs on a range of acid soils (pH less than 5.5). It is generally species-poor, and often grades into wet or dry dwarf shrub heath, although it must always have less than 25% dwarf shrub cover (see heathland, especially D5 and D6). Pioneer annual-rich calcifuge communities on dry sandy soils are included in this category, as are wet acidic grassland typified by species such as Juncus squarrosus (but see marsh/marshy grassland). The following are indicative of acidic conditions when frequent or abundant: Deschampsia flexuosa, Nardus stricta, Juncus squarrosus, Galium saxatile and Rumex acetosella.

Unimproved Acid grassland:Unimproved grasslands are likely to be rare, especially in the lowlands. They may be rank and neglected, mown or grazed. They may have been treated with low levels of farmland manure, but should not have had sufficient applications of fertiliser or herbicide, or have been so intensively grazed or drained. As to alter the sward composition significantly. Species diversity is often high, with species characteristic of the area and the soils and with a very high percentage of agricultural species.In cases of doubt, map as semi-improved and target note the need for further information.

Semi-improved Acid grassland:Semi-improved grassland is a transition category made up of grasslands which have been modified by artificial fertilisers, slurry, intensive grazing, herbicides or drainage, and consequently have a range of species which is less diverse and natural than unimproved grasslands. Such grasslands are still of some conservation value. Semi-improved grassland may originate from partial improvement of acid, neutral or calcareous grassland and should be mapped as such. However, it should be noted that improvement reduces the acid or calcareous character of the grassland, so that this is not always easy to distinguish in the field. Species diversity will generally be lower than in unimproved grassland in the same area. If the signs of improvement listed under B4 are lacking, the grassland is likely to be semi-improved and should be mapped accordingly. Target notes should be made in all of the better quality sites. Surveyors should be aware of the species compositions indicative of semi-improved conditions in the locality of the survey. See also poor semi-improved grassland (B6).

B2 Neutral grassland:

Neutral Grassland Description:Typically enclosed and usually more intensively managed than acid or calcareous grassland (except on roadside verges), this category encompasses a wide range of communities occurring on neutral soils (pH 5.5-7.0). The following are indicative of neutral conditions when frequent or abundant: Alopecurus pratensis, Arrhenatherum elatius, Cynosurus cristatus, Dactylis glomerata, Deschampsia cespitosa, Festuca arundinacea and Festuca pratensis. Lolium perenne may be present, but when abundant it is indicative of improved grassland (see B4).Hay meadows will usually fall within this category. Surveyors should be aware that after cutting, a hay meadow can have the appearance of improved pasture as the new growth comes through.

Included in neutral grassland is a range of grasslands which are inundated periodically, permanently moist, or even water-logged (but see marsh/marshy grassland, B5). Examples are:- inundated grassland with abundant Glyceria species, Alopecurus geniculatus, Poa trivialis and Polygonum hydropiper; water meadows and alluvial meadows; species-poor Deschampsia cespitosa grasslands and grazed Juncus effusus/Juncus inflexus - Holcus lanatus/Deschampsia cespitosa grasslands; wet meadows or pastures where grasses are dominant in the sward (cf. Marsh/marshy grassland, B5) but with species such as Caltha palustris, Filipendula ulmaria, Valeriana species, Juncus species or Crepis paludosa present.

Unimproved grassland:Unimproved grasslands are likely to be rare, especially in the lowlands. They may be rank and neglected, mown or grazed. They may have been treated with low levels of farmland manure, but should not have had sufficient applications of fertiliser or herbicide, or have been so intensively grazed or drained. As to alter the sward composition significantly. Species diversity is often high, with species characteristic of the area and the soils and with a very high percentage of agricultural species.In cases of doubt, map as semi-improved and target note the need for further information.

Semi-improved grassland: Semi-improved grassland is a transition category made up of grasslands which have been modified by artificial fertilisers, slurry, intensive grazing, herbicides or drainage, and consequently have a range of species which is less diverse and natural than unimproved grasslands. Such grasslands are still of some conservation value. Semi-improved grassland may originate from partial improvement of acid, neutral or calcareous grassland and should be mapped as such. However, it should be noted that improvement reduces the acid or calcareous character of the grassland, so that this is not always easy to distinguish in the field. Species diversity will generally be lower than in unimproved grassland in the same area. If the signs of improvement listed under B4 are lacking, the grassland is likely to be semi-improved and should be mapped accordingly.

B3 Calcareous grassland:

Calcareous Grassland Description: These grasslands are often unenclosed, not managed intensively, and occur on calcareous soils (pH above 7.0). Dryas octopetala communities are included. Where the grass is tall, the dominant species is usually either Brachypodium pinnatum or Bromus erectus, whilst species indicative of short, close-grazed and species-rich calcareous turf are Koeleria macrantha, Avenula pratensis, Sesleria albicans, Helianthemum nummularium, Sanguisorba minor and Thymus praecox.

Unimproved grassland:Unimproved grasslands are likely to be rare, especially in the lowlands. They may be rank and neglected, mown or grazed. They may have been treated with low levels of farmland manure, but should not have had sufficient applications of fertiliser or herbicide, or have been so intensively grazed or drained. As to alter the sward composition significantly. Species diversity is often high, with species characteristic of the area and the soils and with a very high percentage of agricultural species.In cases of doubt, map as semi-improved and target note the need for further information.

Semi-improved grassland:Semi-improved grassland is a transition category made up of grasslands which have been modified by artificial fertilisers, slurry, intensive grazing, herbicides or drainage, and consequently have a range of species which is less diverse and natural than unimproved grasslands. Such grasslands are still of some conservation value. Semi-improved grassland may originate from partial improvement of acid, neutral or calcareous grassland and should be mapped as such. However, it should be noted that improvement reduces the acid or calcareous character of the grassland, so that this is not always easy to distinguish in the field. Species diversity will generally be lower than in unimproved grassland in the same area. If the signs of improvement listed under B4 are lacking, the grassland is likely to be semi-improved and should be mapped accordingly. Target notes should be made in all of the better quality sites. Surveyors should be aware of the species compositions indicative of semi-improved conditions in the locality of the survey. See also poor semi-improved grassland (B6).

B4 Improved grassland:

Improved Grassland Description:Improved grasslands are those meadows and pastures which have been so affected by heavy grazing, drainage, or the application of herbicides, inorganic fertilisers, slurry or high doses or manure that they have lost many of the species which once could expect to find in an unimproved sward. They have only a very limited range of grasses and a few common forbs, mainly those demanding of nutrients and resistant to grazing. Lolium perenne, Cynosurus cristatus, Trifolium repens, Rumex acetosa, Taraxacum officinale, Bellis perennis, Ranunculus acris and Ranunculus bulbosus are typical of improved grassland, while stands of dock Rumex species, common nettle Urtica dioica and thistles Cirsium species indicate local enrichment of the soil by grazing animals.
The following signs usually indicate substantial improvement:- bright green, lush and even sward, dominated by grasses (though poaching - causes uneveness); low diversity of forb species; more than 50% Lolium perenne, Trifolium repens and other agricultural species. Fields which have been reseeded in the past and have since become somewhat more diverse are included in this category, but recently reseeded monoculture grassland such as rye grass leys, with or without clover, should be classified under cultivated land (J1). Most amenity grassland should also be classified under J1.

B5 Marsh/marshy grassland:

Marsh/marshy Grassland Description:This is a diffuse category covering certain Molinia grasslands, grassland with a high proportion of Juncus species, Carex species or Filipendula ulmaria, and wet meadows and pastures supporting communities of species such as Caltha palustris or Valeriana species, where broadleaved herbs rather than grasses, predominate. The category differs from swamp (F1) in that the latter has a water table distinctly above the substratum for much of the year and is dominated by reed grasses or large sedges. Unlike marginal vegetation (F2) marsh/marshy grassland occurs on more or less level areas, rather than on the banks of watercourses. It differs from flush (E2) in that bryophytes are not a conspicuous component of the vegetation, also flushes always have a flow or seepage of water through them. The following communities are included in marsh/marshy grassland:- vegetation with a greater than 25% cover of Molinia caerulea, on less than 0.5m of peat (cf. Mire, E); vegetation with less than 25% dwarf shrub cover on peat less than 0.5m deep (cf. heathland, D);vegetation with a greater than 25% cover of Juncus acutiflorus, J. effusus, J. inflexus, Carex species or Filipendula ulmaria, except for grazed Juncus effusus - Holcus lanatus/Deschampsia cespitosa grasslands, which should be classified under neutral grassland, B2;wet meadows and pastures where grasses are subordinate to forbs (cf. wet neutral grassland, B2). Such communities are often rich in plants such as Caltha palustris, Filipendula ulmaria, Valeriana species, Crepis paludosa, Dactylorhiza species, Eupatorium cannabinum, Juncus species and Carex species.If Sphagnum is abundant, refer to the mire classification (E).

B6 Poor semi-improved grassland:

Poor semi-improved Grassland Description:
(* This Phase 1 alphanumeric reference code differs from that used in either the 1984 NCC/RSNC classification or the 1982 SSSI mapping system.)

Where there is a large amount of semi-improved grassland it may be useful to split this category into 'good semi-improved' and 'poor semi-improved', to facilitate re-survey of the better semi-improved grasslands at a later date. This sub-division is optional.Good semi-improved grassland will have a reasonable diversity of herbaceous species, at least in parts of the sward, and is clearly recognisable as acid, calcareous or neural in origin. Such grassland should be left in the semi-improved categories of acid, neutral and calcareous grassland (B1.2. 2.2 and 3.2). Poor semi-improved grassland will have a much more restricted list of species and, being more improved, it is more likely to resemble a species-poor neutral grassland, irrespective of its origin.