“Excluding livestock from endangered woodlands is vital for their conservation and regeneration, but private landholders may need to use more direct action inside many fenced areas to regenerate native plants,” said CSU ecology researcher, Peter Spooner.
In a study of 47 fenced areas that enclosed remnant woodlands containing Grey Box, Yellow Box, Blakely’s Red Gum and White Cypress Pine, Mr Spooner found that 59 per cent of sites contained new native tree seedlings.
“Excluding livestock also increased the cover of native perennial grasses, decreased the proportion of introduced annual pasture plants and reduced soil compaction,” Mr Spooner said.
“In sites where there were more perennial grasses, there were also more tree seedlings. However, where there were more annual plants and shade from existing trees, there were far fewer seedlings, even though there was no grazing.”
Mr Spooner was particularly concerned by the poor regeneration of native shrubs, which grow under trees.
“The shrubs are critical in providing suitable habitats for native animals. In addition to fencing, landholders may need to replant some native species, especially shrubs, or control weeds to successfully regenerate some areas,” he said.
The study sites, located in the NSW Murray River catchment from hills around Holbrook in southern NSW to the dry Riverina plains, were part of the national Greening Australia fencing scheme that commenced in 1996. The study was funded by Greening Australia.
Using funds from the Natural Heritage Trust, remnant native vegetation was fenced off on private land to control grazing and, in some cases, revegetated with native plants.
Mr Spooner is now investigating how land managers in agricultural areas can assist in regenerating native shrubs as part of his PhD studies with Charles Sturt University.