Remove vegetation before seeding/planting
Overall effectiveness category Evidence not assessed
Number of studies: 2
Background information and definitions
Following conversion to arable agriculture or pasture, many grasslands are dominated by a relatively small number of plant species. Removal of this vegetation before sowing seeds of grassland species may aid the germination and colonization of grassland plants.
The studies summarised below removed vegetation using mechanical methods. For evidence relating to the removal of vegetation using herbicide, see ‘Apply herbicide before seeding/planting’ or for burning, see ‘Burn vegetation before seeding/planting’.
Supporting evidence from individual studies
A replicated, randomized, controlled study in 1986 in a former arable field in Sussex, UK (Hutchings & Booth 1996) found that removing vegetation before sowing seeds increased the germination of four grassland plant species compared to sowing without vegetation removal. The average percentage of seeds that germinated for four grassland plant species was higher in plots where vegetation was removed and seeds sown (7.0–45.5%) than in plots where seeds were sown but vegetation was not removed (0.1–1.8%). In April 1986, all vegetation was removed (cut at ground level) from twenty 7 x 5 m plots, and seeds were sown of either Achillea millefolium, Pimpinella saxifraga, Plantago media or Scabiosa columbaria (five plots sown/species). In twenty other plots, seeds were sown but vegetation was not removed. Plots were monitored for seed germination every 1–2 weeks until September 1986.Study and other actions tested
A replicated, controlled study in 2006–2007 in five grassland restoration sites in Belgium (Piqueray et al. 2013) found that removing vegetation, along with removing leaf litter, before sowing forb seeds increased the number of seedlings for one of three sown species compared to sowing alone. For one sown species, pasqueflower Pulsatilla vulgaris, the average number of seedlings was higher in plots where vegetation and litter were removed before sowing (3 seedlings/plot) than in plots where vegetation and litter were not removed before sowing (0.6 seedlings/plot). The two other sown species, mountain clover Trifolium montanum and prostrate speedwell Veronica prostrata, did not germinate in sown plots with or without vegetation and litter removal. In May–August 2007, at each of five sites, vegetation and litter were removed in four 1 x 1 m plots after which 25 seeds of Pulsatilla vulgaris, Trifolium montanum or Veronica prostrata were sown. In another four plots, seeds were sown but vegetation and litter were not removed. All sites were former forest stands that were clear cut and restored to grassland 3–14 years before the study. In May 2008, the number of seedlings in each plot was counted.Study and other actions tested