Background information and definitions
Nurse plants, also known as companion plants or pioneer plants, can be planted alongside focal plants to help the focal plants establish (Padilla & Pugnaire 2006). Nurse plants may benefit focal plants in variety of ways, including: trapping and stabilizing sediments, trapping propagules, mitigating harsh environmental conditions (e.g. temperature fluctuations and strong sunlight), attracting pollinators, deflecting herbivory away from focal species, and/or limiting weed establishment.
Caution: Nurse plant species must be chosen carefully. Species that spread easily or are very strong competitors can cause more harm than good. For example, the non-native mangrove apple Sonneratia apetala has been used to restore Chinese mangroves, but has spread into neighbouring forests (Ren et al. 2009). Use of non-native nurse plants may not always be ethically acceptable.
To be summarized as evidence for this action, studies must have (a) deliberately introduced nurse plants before planting target marsh or swamp vegetation, and (b) reported the effects of the nurse plants on other vegetation, not just the survival or growth of the nurse plants. Studies must have explicitly planted vegetation for its nursing effect. Studies are not summarized as evidence here if they planted target vegetation into existing nurse vegetation (e.g. Egerova et al. 2003; McKee et al. 2007), or examined spontaneous colonization amongst planted nurse vegetation.
Related actions: Introduce nurse plants without introducing target marsh or swamp vegetation.
Egerova J., Proffitt C.E. & Travis S.E. (2003) Facilitation of survival and growth of Baccharis halimifolia L. by Spartina alterniflora Loisel. in a created Louisiana salt marsh. Wetlands, 23, 250–256.
McKee K.L., Rooth J.E. & Feller I.C. (2007) Mangrove recruitment after forest disturbance is facilitated by herbaceous species in the Caribbean. Ecological Applications, 17, 1678–1693.
Padilla F.M. & Pugnaire F.I. (2006) The role of nurse plants in the restoration of degraded environments. Frontiers in Ecology and the Environment, 4, 196–202.
Ren H., Lu H., Shen W., Huang C., Guo Q., Li Z. & Jian S. (2009) Sonneratia apetala Buch.Ham in the mangrove ecosystems of China: an invasive species or restoration species? Ecological Engineering, 35, 1243–1248.