RESTORATION EVIDENCE

Action: Add mulch to control grass and sow seed Shrubland and Heathland Conservation

Key messages

  • One randomized, controlled study in the USA found that adding mulch, followed by seeding with shrub seeds, increased the seedling abundance of one of seven shrub species but did not reduce grass cover.

Supporting evidence from individual studies

1 

A randomized, controlled study in 1997–1999 in sagebrush scrub habitat that had been invaded by grass and burnt by wildfires in California, USA (Cione et al. 2002) found that adding mulch, followed by seeding with shrub seeds, increased the seedling abundance of one of seven shrub species but did not reduce grass cover. After one year, areas where mulch and shrub seeds were added did not have a significantly higher number of shrub seedlings for two of seven species (1 seedlings/m2) than areas where mulch and seed were not added (0 seedlings/m2). There was also no significant difference in grass cover between areas where mulch and seeds had been added (76%) and areas where neither mulch, nor seeds were added (84%). In 1997 mulch was added to five randomly located 5 m x 5 m plots which were subsequently sown with seeds from native shrubs, while in five other plots no mulch or seeds were added. In spring 1997 plots were surveyed for grasses using two 0.25 m x 0.5 m quadrats/plot and two 0.5 m x 1 m quadrats/plot for shrubs.

Referenced papers

Please cite as:

Martin P.A., Rocha R., Smith R.K. & Sutherland W.J. (2018) Shrubland and Heathland Conservation. Pages 447-494 in: W.J. Sutherland, L.V. Dicks, N. Ockendon, S.O. Petrovan & R.K. Smith (eds) What Works in Conservation 2018. Open Book Publishers, Cambridge, UK.