Add mulch and fertilizer to soil (alongside planting/seeding)

How is the evidence assessed?
  • Effectiveness
  • Certainty
  • Harms

Study locations

Key messages

  • A randomized, controlled study in the USA found that adding mulch and fertilizer, followed by sowing of seeds increased the abundance of seedlings for a minority of shrub species. The same study found that adding mulch and fertilizer, followed by sowing seeds had no significant effect on grass cover.

About key messages

Key messages provide a descriptive index to studies we have found that test this intervention.

Studies are not directly comparable or of equal value. When making decisions based on this evidence, you should consider factors such as study size, study design, reported metrics and relevance of the study to your situation, rather than simply counting the number of studies that support a particular interpretation.

Supporting evidence from individual studies

  1. A randomized, controlled study in 1997–1999 in a sagebrush scrub shrubland that had been invaded by grass and burnt by wildfires in California, USA (Cione et al. 2002) found that adding mulch, followed by addition of nitrogen fertilizer, and seeding with shrub seeds increased the seedling abundance of two of seven shrub species but did not reduce grass cover after one year. Areas where mulch, fertilizer and shrub seeds were added had more shrub seedlings for two of seven species (1–2 seedlings/m2) than areas where mulch, fertilizer and seed were not added (0 seedlings/m2). There was no difference in grass cover between areas where mulch, fertilizer and seed had been added (84%) and areas where mulch, fertilizer and seed were not added (84%). In 1997 mulch and fertilizer were 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 fertilizer 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.

    Study and other actions tested
Please cite as:

Martin, P.A., Rocha, R., Smith, R.K. & Sutherland, W.J. (2020) Shrubland and Heathland Conservation. Pages 483-525 in: W.J. Sutherland, L.V. Dicks, S.O. Petrovan & R.K. Smith (eds) What Works in Conservation 2020. Open Book Publishers, Cambridge, UK.

Where has this evidence come from?

List of journals searched by synopsis

All the journals searched for all synopses

Shrubland and Heathland Conservation

This Action forms part of the Action Synopsis:

Shrubland and Heathland Conservation
Shrubland and Heathland Conservation

Shrubland and Heathland Conservation - Published 2017

Shrubland and Heathland synopsis

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