Sandpipers Bartramia longicauda. By creating more bare ground, burning also
favors more annual plants, particularly if carried out frequently. In hay meadows,
annual cutting is usually followed by “aftermath” grazing, which is important in
maintaining high plant species-richness of agriculturally unimproved grasslands
(Smith and Rushton 1994). Removal of cuttings will prevent them smothering
re-generating seedlings and other small plants, but leaving them will provide tem-
porary cover for small mammals and some invertebrates until the vegetation has
grown again.
The primary considerations when deciding on cutting or burning regimes are
their timing and frequency. Timing is influenced by the timing and duration of
the breeding season (see below), and by the times of year particular sward heights
are required by species of interest. The frequency of cutting and burning influ-
ences sward condition in a given area, particularly the quantity of accumulated
litter. Thus in dry prairies in Missouri, USA, cutting on a rotation of 1–2 years is
considered best for Grasshopper Sparrows Ammodramus savannarum that
require a light litter layer, while a rotation of 2 years or more is considered better
for Henslow’s Sparrows (Swengel and Swengel 2001). Cutting on a rotation of
more than 1 year, different patches in different years, can also be used to produce
coarse-scale variation in sward structure, by creating a mosaic of patches at
different stages of re-growth. Rotational management will therefore help main-
tain a continuity of suitable habitat for invertebrates and small mammals over a
given area.
Altering the height at which the sward is cut can influence sward conditions.
In agriculturally managed grasslands, cutting is carried out close to ground level
to maximize the offtake, and such management also helps to maintain high
species-richness of plants by creating gaps for plant regeneration (see above).
Regular cutting at a height of 15 cm (“topping”) is used to maintain a dense
sward of 15–20 cm high to discourage flocks of Starlings Sturnus vulgaris, gulls,
corvids, and plovers from grassland at airports, in order to reduce bird strikes
(Civil Aviation Authority 1998). Altering the height of cutting can also be used to
provide preferred sward heights for birds at particular times of year, for example,
for wintering geese (Vickery et al. 1994).
14.5.3Effects of grazing on sward condition
Grazing differs fundamentally from cutting and burning in that it removes the
vegetation piecemeal, and more selectively, at least at low to medium grazing
intensities. Grazing also produces dung, and its associated invertebrates can be
important in the diet of some birds, notably Red-billed Choughs Pyrrhocorax
pyrrhocorax(Roberts 1982). Trampling by stock can create a continuity of bare
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