Biodiversity Wins for South West Reforestation Project as Establishment Rate of Native Species Smashes Targets

Named after the creek that passes through the property, Pinjalup is a 251 hectare site located 90km north of Albany. The property is perfectly positioned to link up existing nature corridors and contribute to the achievement of the Gondwana Link vision, one of the largest and most ambitious conservation projects in Australia’s history.

The Southwest of Australia is one of 34 global biodiversity hotspots, recognised for its species richness.  It is estimated that 32% of Australia’s plant species are found here, of which approximately 79% are endemic. The vision of the Gondwana Link and the organisations/community members involved is to protect and restore ecological connectivity and biodiversity across south-west Australia, from the Karri forest of the SW corner to the woodlands and mallee bordering the Nullarbor Plain.

At Pinjalup, the aim was to rehabilitate an area to recreate bushland which, as far as possible, mirrors what naturally would occur, a varied and diverse habitat with up to 550 plant species.

At a pivotal time for the project, almost three years on from the initial planting, Carbon Neutral staff visited the Pinjalup site with local biodiversity restoration consultant Wendy Bradshaw.

Wendy, then working as part of the South Coast Natural Resource Management team, designed the original plan for the site – carefully selecting suitable native shrubs and trees to plant and preparing the land for rehabilitation.

When Carbon Neutral took on Pinjalup in 2010 the site was marginal farming land. “The majority of the land was not suitable for crops or grazing. The land was prone to water logging and salinity in parts, and available stock water was brackish,” said Wendy.

“From an ecological perspective, biodiversity was the best use for the land. In order to maintain our landscape we need a critical mass of native vegetation to support ecosystem processes that keep the land, and those that live on it healthy. From an agricultural perspective, relatively unproductive land like Pinjalup was an obvious choice for biodiversity conservation,” said Wendy.

The plan was to optimise biodiversity at each vegetation level to maximise habitat values as well as improve ecosystem function, including: a ground layer with native grasses, ground covers, rushes and low shrubs to create dense habitat for fauna that is vulnerable to predation such as birds, reptiles and small mammals; the mid-storey including medium to tall shrubs and the tree layer including small to larger trees and mallees.

The planting design attempted to mimic locally-occurring natural vegetation systems.  “The first step was to map out the condition of the land – the soil types were described and soil salinity levels recorded across Pinjalup,” said Wendy. “A vegetation survey of the bushland on the property and surrounding areas was also carried out to help inform species selection.”

In July and August 2010, approximately 163,250 seedlings and 57.6kg of seed were planted at Pinjalup. Over 113 different native species were planted.

“The design included a high density of rushes and shrubs to help capture rainfall and sunlight, provide habitat, and restore soil health through increasing organic matter cover, rootmass and improved hydrological balance,” said Wendy. “Dense understorey creates a microclimate that helps insulate the vegetation from extreme weather events and promotes resilience and self-sustainability.”

Almost three years on, a large percentage of native species planted at Pinjalup are thriving. The target was to achieve 1,250 stems per hectare, but progress monitoring shows a result of approximately 5,300 stems per hectare across 158 planted hectares.

“Despite the challenge of the 2010 record drought, I’m really pleased with the outcome. There is really good biodiversity across all three levels of vegetation. I’m confident that any sparsely populated areas will regenerate naturally and achieve good cover in time,” said Wendy.

“Pinjalup has a great mix of native species and the establishment rate of the trees, shrubs and ground layer is extremely positive.”

“I’m excited about the result – a lot of animals and insects are going to live here. During my first evening monitoring visit at Pinjalup I straightaway saw white fronted chats flitting around the shrubs and a brown goshawk sitting on the fence. This can only get better.”

Pinjalup’s revegetation is complete and the planting connects existing bushland in the area, while absorbing greenhouse gas emissions. Pinjalup is now ready for its next owner, and funds received from the sale of the property will go towards Carbon Neutral’s future ‘Trees for Tomorrow’ revegetation projects in Southwest Australia.

There is also a remaining 18 hectares area available for planting should owners wish to be fully immersed in all stages of a biodiversity project or have some form of farm forestry which could provide an additional income.