Establishing native plants in a weedy riparian environment

Abstract

Riparian zones are important for influencing stream habitat and water quality. Efforts to populate these areas with native species are frequently hindered by fast-growing weed species. A trial was installed to examine riparian establishment alongside the Sherry River in the Motueka river catchment with seven native species and four weed-control treatments. After 2 years, herbicide use significantly improved seedling survival compared with the other weed-control treatments, but weed mats promoted greater seedling height and crown diameter growth. Seedling survival and growth varied significantly with species. After comparisons of costs and practical issues, weed mats were concluded to provide the most suitable weed control. Cordyline australis had the highest survival rate, developed the most crown area and performed well in terms of height increment; Pittosporum tenuifolium and Plagianthus regius also performed well. All three native species are recommended for use in further plantings at this and other similar locations.

Black Plastic Mulch or Herbicide to Accelerate Bur Oak, Black Walnut, and White Pine Growth in Agricultural Riparian Buffers?

“…Tree species selection is sometimes more important to increase survival rate than the use of vegetation treatments [75]. However, in other riparian afforestation studies, where survival rates were low, competing vegetation management was a determining factor affecting tree survival [18,31]. High survival rates were potentially linked to the high soil fertility and the good soil moisture conditions that characterised the studied riparian zone, which has a good hydrological connectivity with the stream (B. Truax and J. Fortier, field observations).…”

Integrated catchment management—interweaving social process and science knowledge

“…Examples where these processes were seen to better inform issues and build stakeholder cohesion include the development of a GIS system with Motueka iwi (Harmsworth et al 2005), sharing stakeholder perspectives on sediment in a learning group setting (Allen et al 2011), the use of anecdotal records from trout fishermen to better understand the sediment impacts of large floods (Loftus 2009), and the actions of the Sherry River Catchment Group to improve water quality through improved farm management practices (NZ Landcare Trust 2010; Smaill et al 2011). …”

Seedling Survival in Forest Re-vegetation Sites within Wellington Peninsula

“…For example, manuka (Leptosperum scoparium) is used across New Zealand in re-vegetation projects as a nurse plant (QEII National Trust 1997). On the other hand, weeds and grasses are detrimental to the growth and establishment of native seedlings (Sullivan et al 2009;Smaill et al 2011). Finally, the negative effects of browsing and grazing of introduced animals on seedling establishment are well documented (Husheer et al 2006;Wilson et al 2006;Bee et al 2007;Camara 2011).…”

“…Therefore, maximising the survival rates of the seedlings after they have been transplanted is a key step in any re-vegetation project. In order to maximise seedling survival rates, it is necessary to understand the processes involved in plant mortality (Porteous 1993;Smaill et al 2011). By understanding these processes, agencies executing revegetation projects can make informed decisions regarding timing and necessary management in their transplanting approach.…”