Reduce cutting frequency on grassland
Overall effectiveness category Awaiting assessment
Number of studies: 6
Background information and definitions
Productive grasslands used for silage are intensively managed, with frequent cutting resulting in a short and uniform sward (Bubová et al. 2015). While mowing is important for maintaining open grassland, reducing cutting frequency allows some vegetation to grow taller, increasing structural complexity and floral diversity (Morris 2000), and this may provide more suitable habitat for some grassland butterflies and moths (e.g. Elligsen et al. 1997).
For studies on reducing cutting frequency alongside other reductions in management intensity, such as reduced chemical input, see “Reduce management intensity on permanent grasslands (several interventions at once)”. For studies on removing grassland management entirely, see “Cease mowing on grassland to allow early succession”. For studies on increasing grassland management, see “Increase grazing intensity or cutting frequency on grassland”.
Elligsen H., Beinlich B. & Plachter H. (1997) Effects of large-scale cattle grazing on populations of Coenonympha glycerion and Lasiommata megera (Lepidoptera: Satyridae). Journal of Insect Conservation, 1, 13–23.
Morris M.G. (2000) The effects of structure and its dynamics on the ecology and conservation of arthropods in British grasslands. Biological Conservation, 95, 129–142.
Bubová T., Vrabec V., Kulma M. & Nowicki P. (2015) Land management impacts on European butterflies of conservation concern: a review. Journal of Insect Conservation, 19, 805–821.
Supporting evidence from individual studies
A replicated, site comparison study in 2003–2006 in 16 hay meadows in central Slovakia (Kulfan et al. 2012) found that meadows which were mown once/year had a similar abundance of meadow brown Maniola jurtina butterflies and caterpillars to meadows mown twice/year, but a higher abundance than abandoned, unmown meadows. In meadows mown once/year, the abundance of both meadow brown adults (12–81 individuals/transect) and caterpillars (10–26 individuals/transect) was not significantly different from meadows mown twice/year (adults: 14–45; caterpillars: 1–8 individuals/transect). However, meadows mown once/year had a higher abundance of both adults and caterpillars than abandoned, unmown meadows (adults: 6–33; caterpillars: 1–2 individuals/transect). Four meadows at the edge of oak-hornbeam forests and four open meadows were mown once/year in late June or July. Four further meadows were mown twice/year in late May–early June and from late July–September, and four abandoned meadows had not been mown for 15 years. From June–August 2003–2005, adult butterflies were counted 4–7 times/year on seven 50-m transects in each habitat type. In May 2005 and 2006, caterpillars were surveyed at night, 1–4 times/year, by sweeping vegetation with a net along ten 50-m transects in each habitat type (60 sweeps/transect).Study and other actions tested
A replicated, site comparison study in 2007 in a grassland and woodland reserve in the Czech Republic (Slamova et al. 2013) found that occasionally mown grasslands had a higher abundance of Scotch argus Erebia aethiops than intensively mown grasslands. On occasionally mown grasslands, the abundance of Scotch argus males (9 individuals/ha) and females (5 individuals/ha) was higher than on intensively mown grasslands (males: 3; females: 2 individuals/ha). However, the abundance of Scotch argus males (19 individuals/ha) and females (13 individuals/ha) was highest on temporarily abandoned grasslands, and similar on grazed grasslands (males: 7; females: 4 individuals/ha) to occasionally mown grasslands. Within a 55-ha reserve, 27 grasslands (128–6,072 m2) were managed by either occasional mowing, intensive mowing, or sheep and goat grazing, or were temporarily abandoned. On 33 days from July–August 2007, butterflies were caught, individually marked, and recaptured at each site.Study and other actions tested
A replicated, randomized, paired, controlled study in 2007–2010 in four meadows in Őrség National Park, Hungary (Kőrösi et al. 2014) found that grassland mown once/year had a similar abundance of scarce large blue butterflies Phengaris teleius to grassland mown twice/year, but a higher abundance than abandoned, unmown plots. Three years after management began, the number of scarce large blue butterflies in plots mown once/year in May (0.86 individuals/plot/day) or September (0.94 individuals/plot/day) was similar to the number in plots mown twice/year (0.70 individuals/plot/day). All mown plots had more butterflies than abandoned plots (0.28 individuals/plot/day). In May 2007, four meadows were each divided into four equal-size plots, and one of four management regimes was randomly applied to each plot. Three plots/meadow were mown for four years, either once/year in May, once/year in September, or twice/year in May and September, all with cuttings removed. The fourth plot in each meadow was abandoned (not mown). In July 2007 and 2010, butterflies were surveyed for five minutes, 15–20 times/year, in each of three or four 20 × 20 m squares/plot.Study and other actions tested
A replicated, randomized, paired, controlled study in 2008–2012 on a farm in Berkshire, UK (Woodcock et al. 2014) found that grasslands established with flowering plants which were cut once/year had a greater abundance and species richness of pollinators (including butterflies) than grasslands cut twice/year. When sown with a seed mix including legumes or legumes and other non-woody, broadleaved plants (forbs), plots cut once/year had a higher abundance (8–91 individuals/plot) and species richness (3–8 species/plot) of pollinators than plots cut twice/year (abundance: 6–52 individuals/plot; richness: 3–6 species/plot). In plots sown with grasses alone, pollinator abundance (0–3 individuals/plot) and species richness (0–2 species/plot) were lower regardless of cutting frequency. In spring 2008, forty-eight 875-m2 plots were sown with one of three seed mixes: a “grass only” mix of five species (30 kg/ha, cost: €83/ha); a “grass and legume” mix of five grasses and seven agricultural legumes (34 kg/ha, €120/ha); or a “grass, legume and forb” mix of five grasses, seven legumes and six non-legume forbs (33.5 kg/ha, €190/ha). Half of the plots were cut to 10 cm once/year in May, and half were cut to 10 cm twice/year in May and August. In May, July and August 2009–2012, butterflies, bees (Apidae) and hoverflies (Syrphidae) were surveyed three times/year on two parallel 20 × 2 m transects/plot.Study and other actions tested
A replicated, site comparison study in 2014 in 26 grasslands in Germany (Mangels et al. 2017) reported that grasslands managed with reduced cutting frequency (sometimes also grazed) supported more moth species than more frequently mown grasslands. Results were not tested for statistical significance. Grasslands managed with less frequent cutting had more moth species (99 species) than grasslands managed with more frequent cutting (79 species). From 2006, across three regions, nine grasslands were managed by mowing (often with nitrogen fertilization) at low (0–1 cuts/year) or high frequency (2 cuts/year), nine were managed by grazing (by cattle, sheep or horses at 26–520 livestock units/ha/year), and eight were mown and grazed (1–2 cuts/year; 76–163 livestock units/ha/year). Moths were collected once/month from nine grasslands in each of two regions (May–August 2014), and from eight grasslands in one region (June–July 2014). Each night, a 12 V actinic and black-light trap were placed in the centre of each of three grasslands for 138–317 minutes/night.Study and other actions tested
A replicated, site comparison study in 2014–2015 in a mixed farming region in Lombardy, Italy (Luppi et al. 2018) found that meadows cut less frequently had a similar abundance and species richness of butterflies to more frequently cut meadows, but a lower abundance and species richness compared to uncut meadows. The abundance and species richness of butterflies were similar in meadows cut once, twice or three times/summer (data presented as model results). However, both the abundance and species richness of butterflies were lower on meadows which were cut at least once than on meadows left uncut (data presented as model results). See paper for details on individual species groups. In 2014 and 2015, meadows within an arable landscape were cut 0–3 times between April and September each year. From April–September 2014–2015, butterflies were surveyed along 44 transects, divided into 8–26 × 50-m sections. In 2014, thirty transects were surveyed once/month, and in 2015 fourteen different transects were surveyed twice/month. Only transect sections which passed through meadows were included (number not specified).Study and other actions tested