Category Archives: South Australia

Grey Box grassy woodland restoration: Mandilla Reserve, Flagstaff Hill, South Australia

Key Words:  Minimal disturbance, bush regeneration, Eucalyptus microcarpa, volunteer, Bush For Life

The Site:  Grey Box (Eucalyptus microcarpa) Grassy Woodland is listed as an endangered ecological community under the EPBC Act 1999. This ecological community was once widespread on the drier edge of the temperate grassy eucalypt woodland belt of south-eastern Australia. In South Australia, this community occupies less than 3 percent of the area it once did before European settlement. One of the remaining suburban remnants of this community can be found in Mandilla Reserve, Flagstaff Hill, SA. The reserve is surrounded by suburban houses and remains under threat from weed and pest invasion, lack of recruitment of canopy species plus degradation associated with urban encroachment (pollution runoff, rubbish, excessive stormwater). Since 1996 the Bush or Life program together with the City of Onkaparinga have supported community volunteers to care for and manage the bush regeneration work within the reserve. The objective was to restore the highly degraded Grey Box remnant into a woodland community representing the unique diverse vegetation it once housed.

Geoff and Barbara Moss, volunteers at Mandilla Reserve

Works:   Two very dedicated community members adopted the site in 1996 and began visiting on average 3 times per week. They used minimal disturbance bushcare techniques to tackle a carpet of bulb weeds such as Sparaxis (Sparaxis bulbifera), Soursob (Oxalis pes-caprae), Bridal Creeper (Asparagus asparagoides) and Cape Tulip (Moraea flaccida) mixed with highly invasive annual and perennial grass species. In the surrounding degraded areas, some strategic planting was also carried out using Grey Box (Eucalyptus microcarpa), Sticky Hop Bush (Dodonaea viscosa) and Sweet Bursaria (Bursaria spinosa) and local sedge seedlings. Four areas were also hand direct seeded with native grasses to encourage ground cover recruitment and discourage weeds. All seed used was collected on site to ensure local provenance was maintained.

The flourishing Grey Box Grassy Woodland now found on the reserve

Success of the combination of natural regeneration and supplementary plantings

Results After thousands of volunteer hours, extensive regeneration of natives occurred on site. The volunteers’ work has transformed the reserve into a flourishing area of lilies, native grasses and understorey shrubs. Today, the vegetation in the reserve is virtually weed free and even native orchids are beginning to return. In addition, the area that the bushland covers has expanded as a result of the planting and direct seeding. Since these works, natural regeneration has also been observed of native sedges including Senecio, Carex, Juncus and native grasses.

Lessons learned:  Regular follow up for several years is vital to the success of any primary clearance work whether or not minimal disturbance techniques are used. Facilitated regeneration can be successfully used with bush regeneration providing it is strategic and complementary to and considerate of existing natural regeneration processes. Maintenance of the plantings or hand direct seeding is also vital to minimise competition from weeds and ensure their success.

Acknowledgements: This site is owned by the City of Onkaparinga Council and is managed in partnership with Trees For Life who train and support volunteers through its Bush For Life program. Thanks goes to Geoff and Barbara Moss, the site’s main volunteers.

Contact:  Jenna Currie, Bush For Life Regional Coordinator, Trees For Life jennac@treesforlife.org.au

Research Road Restoration, Strathalbyn, South Australia

Key Words: Minimal disturbance, bush regeneration, Eucalyptus fasciculosa, volunteer, Bush For Life.

The Site: In June 1996 Trees For Life (TFL), a community based not-for-profit organisation, established a volunteer bush regeneration site (known as a Bush For Life site) on a 1.4km long, one chain wide roadside remnant on Research Road about 6km south of Strathalbyn, SA.  At this stage the road was still being used as a vehicle track.  The vegetation was a very diverse Pink Gum (Eucalyptus fasciculosa) Open woodland with occasional mallee eucalypts, a shrub understorey, sedge and herbaceous groundcover and native grasses with many locally rare and vulnerable species including the nationally vulnerable Silver Daisy-bush (Olearia pannosa ssp. pannosa ).  The largest weed problem was Bridal Creeper  (Asparagus asparagoides) which blanketed the site in the cooler, wetter months.  Other threats to the understorey diversity included broadleaf weeds typical of the dry, agricultural landscapes of the lower Murray Plains.  These weeds included Pincushion(Scabiosa atropurpurea), Wild Sage (Salvia verbenaca) and Horehound (Marrubium vulgare ).

Diverse grassy understorey found on the site

Works:  Volunteers worked on a section of the 1,400m long, one chain wide road reserve, using minimal disturbance techniques. The regenerators very carefully removed Bridal Creeper, broad leaf weeds and weed grasses; but they had to contend with the continual degradation of the remaining area. It was really only a heavily rutted, two-wheel track suitable for dry weather use only, but was subjected to indiscriminate and illegal use through all seasons, including rubbish dumping, firewood collection and “bush-bashing”.

The Alexandrina Council closed the road to motor vehicles in September 2008 and it has been allowed to recover now for 4 years.  After the road closure, discussions between Council and TFL centred on whether to leave the vehicle track to regenerate by itself or to “rip” the track to fill in the ruts and promote germination. As ripping the track was predicted to have have promoted prolific broadleaf and grassy weed establishment, particularly given the close proximity of weedy agricultural land adjacent to the linear reserve, the BFL principle of minimal disturbance prevailed and the track was left to regenerate without other intervention.

Before road closure

Results: Today there is a proliferation of native species germinating on the track, with native regeneration on the track itself far outweighing the weed regeneration.

The ruts have filled with leaf litter and have encouraged the germination of spear grasses Austrostipa sp.) and wallaby grasses(Austrodanthonia sp.). As the volunteers discover new seedlings they protected them with branches; but regeneration has become so significant that this is no longer practical.  .

Many Mallee Honey-myrtle (Melaleuca acuminata) and Dryland Tea-tree (Melaleuca lanceolata) seedlings have germinated and are thriving in bare patches.  Many other species are also germinating, including: Golden Wattle (Acacia pycnantha), Hakea Wattle (Acacia hakeoides,) Sweet Bursaria (Bursaria spinosa), eucalypts (Eucalyptus spp.), Ruby Saltbush (Enchylaena tomentosa), Climbing Saltbush ( Einadia nutans ssp. nutans), Old Man’s Beard (Clematis microphylla var. microphylla), Australian Bindweed (Convolvulus sp., and New Holland Daisy (Vittadinia sp.). Black-anther Flax-lily (Dianella revoluta, Mallee Blue-flower (Halgania cyanea,),  Rosemary Dampiera (Dampiera rosmarinifolia ) and Quandong ( Santalum acuminatum) are spreading from the sides onto the track. Areas where once a vehicle could drive have now been reduced to a narrow walking track between seedlings.

Native grasses regenerating on the road after closure

Treatment with Bridal Creeper rust (Puccinia myrsiphylli) began in 2004/2005 with wider and more intense applications applied every year from 2008. In the last couple of years rust has established itself over a large proportion of the site with very little flowering and fruiting detected during 2011.  Volunteers carefully treat plants at both ends of the site by ‘tonging’ with glyphosate  (i.e. using tongs with sponge tips as herbicide applicators) which has been very successful.  Through careful and consistent work, most of the broad-leaved weeds have been virtually removed from site, with only isolated germinations being detected and removed. One other weed – : Soursob (Oxalis pes-caprae – is prolific on site; and has yet to be targeted for control.

Rabbits re-entered the site early in 2006 and by mid-2008 had bred up to occupy 15 locations on site. They caused significant damage to the native vegetation until controlled by baiting in March 2010. The increase in native grasses in the areas treated has been significant.

Lessons learned:  Four significant events have had the greatest effect on this turnaround: the road closure, the control of rabbits, the establishment of Bridal Creeper rust and most significantly the consistent hard work of the site’s Bush For Life volunteers.

Acknowledgements:  This site is owned by the Alexandrina Council and is managed in partnership with Trees For Life who train and support volunteers through its Bush For Life program.

Contact:  Sue Bradstreet.  Regional Coordinator, Trees For Life sueb@treesforlife.org.au

Volunteers Maggie Hincks and Dean Mortimer assisting the regeneration

Basketweaving for ecosystem conservation – Coorong, South Australia

Ellen Trevorrow, Tom Trevorrow and Joan Gibbs

Our concerns for the future supply of our basketweaving rushes (Cyperus spp.) are at the heart of our teaching at Camp Coorong for Race Relations Cultural Education.  The rushes are continually being depleted by stock grazing, mowing, weed sprays and neglect of our waterways and Wetlands of International Significance. The Murray River, Lakes and Coorong were suffering and drying from the 8-year drought and from 200 years of mismanagement of our waterways.  We had turned to using recycled fibres such as string, garden twine and wire. In response to this need for materials from the land, we created an artistic working group, Ngarrindjeri Eco-Art Coop (NEAC),  to embrace the principle of using local materials that would not harm the Earth. Recycling discarded items into art gives new meaning and value to materials that could become an environmental hazard.

Fig. 1. Ellen Trevorrow and NEAC teacher, Jelina Haines, with woven trousers from recycled string.

In the last two years several cultural, spiritual ceremonies were held to bring back the water to the River and the Coorong estuary, to help our totems (plant and animal ngatjis).  In 2009, we were graced by a visit with Grandmother Agnes Pilgrim, who came to Camp Coorong to give a water blessing to bring back the healing waters to the land. Many community members danced and sang to the waters and apologised to the ngatjis for their neglect.  In 2010, the first Ringbalin ceremony was conducted at significant places along the length of the Murray Basin and Rivers, to bring back the health of the river system.  The Talkindjeri Dancers, led by the Ngarrindjeri elder, Major Sumner, travelled for two weeks along the river, stopping at towns along the way to meet with people who joined in the dancing and ceremony on the River. At the end of the river, as Talkindjeri danced on Brown’s Beach at Lake Albert near Meningie, the rains began and the drought was broken.  The rushes returned and the Murray River soon flowed again to the Southern Ocean.

Fig. 2. Tom and Ellen Trevorrow, Ngarrindjeri leaders at Camp Coorong for Race Relations and Cultural Education.

Although the basketweaving plants are growing once again, we are still conscious of the care and use of the weaving rushes. We always balance our need to collect rushes against the supply and reproduction of healthy plants and healthy country. Our ngatjis, the local plants and animals, tell us how we are going, and what we should do to keep the Coorong alive.  Now the Working on Country crews are growing the rushes and planting them out in country, hoping to sustain the future of basketweaving and culture.  Ngarrindjeri people have been relentless about asking the Murray Darling Basin Commission to ensure cultural flows are considered as part of critical human needs.  We also ask that cultural flows reach all parts of the River to sustain our ngatjis, the native plants and the fish stocks. We believe that when our ngatjis die, we die.

Contact: Ellen and Tom Trevorrow, Camp Coorong, Box 126, Meningie, SA 5264, Australia. Tel: +61-8-8575-1557; Fax: +61-8-8575-1448; and Joan Gibbs, University of SA, Mawson Lakes, SA 5095, Australia. Tel: +61-8-8302-5164.

Seagrass restoration off the Adelaide Coast via facilitating natural recruitment

Key words: Amphibolis, nanotechnology, seagrass loss, eutrophication

Jamie Quinton

Over the past 50+ years, more than 5,000 ha of seagrass has been lost along the Adelaide metropolitan coast, largely due to excessive nutrient inputs. Following substantial investment in reducing nutrient inputs, limited natural recolonisation has been observed. This is possibly due to sediments now mostly being too mobile for seagrasses to colonise.

The trial. An experiment was carried out to stabilize areas adjacent to existing seagrass meadows, deploying hessian sand bags to provide a stable substrate for the recruitment of Amphibolis seedlings. These seedlings are produced viviparously by the parent plant and have a ‘grappling hook’ for attachment to the substrate.

Hessian sand bag covered by an outer layer of coarse-weave hessian

Various types of sand bag were trialed, with the most effective being a standard hessian bag covered with an outer layer of coarse-weave hessian. These bags can simply be dropped over the side of a boat, and do not require divers to deploy them, thus substantially reducing the coast of restoration. Densities of recruits averaged 150-350 seedlings per m² for different treatments, with individual sand bags attracting densities up to ~900 seedlings per m². Long-term survival (i.e. 3 years or more) occurred for up to 72 individuals per m², although many treatments failed over this duration. Preliminary estimates suggest that restoration costs could be less than $10,000 per ha, provided that long-term success and eventual meadow formation can be achieved. Initial studies of the bags suggested that spatial configuration was not important.

Hessian sand bag with Amphibolis recruits after six months

Lessons learned and future directions: The key issue so far has been the inconsistent quality of the hessian used for the bags – some batches deteriorate rapidly leading to loss of all seedlings, whereas others last longer. The focus is now on trialling nanotechnology to improve the hessian longevity, while still retaining its long-term biodegradability. There is some suggestion that half-buried bags also perform better, possibly due to water flow through the sand in the bags, and this needs further study.

Stakeholders and funding bodies: SA Department of Environment & Natural Resources, SA Water, Adelaide & Mount Lofty Ranges Natural Resource Management Board, Australian Research Council, South Australian Research & Development Institute, Flinders University

Contact information: Dr Jason Tanner, Principal Scientist – Marine Environment & Ecology, SARDI Aquatic Sciences, PO Box 120, Henley Beach, SA. 5022. Tel: +61 8 8207 5489 Email: jason.tanner@sa.gov.au