Restoration of Grassland Communities

The Grassy Groundcover Research Project

Much of the native vegetation of south-eastern Australia consists of complex herbaceous plant communities comprising tussock grasses interspersed with a rich variety of seasonally colourful wildflowers. These once expansive communities occurred as the ground layer in open woodland or in vast areas of treeless grasslands. Over the past two hundred years these plant communities have been fragmented and modified to the extent that they are now considered to be among Australia’s most endangered.

Over the last two decades, a series of studies at the University of Melbourne’s Burnley Campus have investigated the establishment of indigenous herbaceous communities via direct seeding, focussing on issues such as seed collection, seed production, seed quality, site preparation and the use of multi-species seed mixtures. Findings from these studies indicate considerable potential for broad-scale grassland restoration using direct seeding.

To capitalise on these developments, and utilise the skills and expertise of a state-wide network of vegetation specialists, landholders and community interest groups, The University of Melbourne, in partnership with Greening Australia (Victoria), is undertaking a three-year, multi-regional grassland/grassy woodland restoration project funded by the Natural Heritage Trust (NHT). Entitled the Grassy Groundcover Research Project (GGRP), its objective is to further develop the establishment of these complex communities using direct seeding.

The GGRP is establishing a series of direct-sown species-rich grassland and grassy woodland understorey demonstration sites across western Victoria. Each will provide practical and experimental testing of the techniques needed to expand the range of these highly threatened vegetation communities and in doing so, enhance the opportunity for landholders and land managers to apply these techniques elsewhere.

The GGRP has thirteen restoration field sites within the Wimmera, North Central, Glenelg Hopkins, Corangamite & Port Philip regions. These sites are situated on a variety of land tenures including private, municipal and government. Results from the first of three annual sowings have provided very encouraging outcomes, with many grass and forb species germinating and establishing successfully in the field. Experimentation has focused on site preparation and weed control measures. 

The project has also established a series of seed production sites. These have provided supplementary seed sources for field sowings and will contribute to developing general protocols for seed production of herbaceous species. In summary, the GGRP aims to provide techniques that will allow for the reintroduction of complex functional grassland communities on private and public lands. This will, in tandem with adequate conservation and management practices, form a major step in reversing the ongoing decline in the extent of indigenous grassy communities in this State.

A number of research topics associated with the GGRP are available at honours and postgraduate level.

The following honours projects are available:

Investigations of dormancy and germination of fresh and/or stored seed of woody or herbaceous species.

Understanding the germination capacity of a species' seed is fundamental information for utilising that species in traditional breeding programs, for the efficient production of nursery-grown seedlings for horticulture, revegetation and forestry, and for direct sowing of single-species or complex seed mixes. Recent and current research has focussed on native grasses and forbs for grassland reconstruction and on a range of saltbush species for revegetation. This project will involve an investigation of dormancy and germination of one or more species. It will include an examination of external and internal seed morphology and the species' responses to a range of dormancy treatments and germination environments. Supervisor: John Delpratt

Difficult-to-germinate plant species indigenous to Victoria.

A number of plant species are excluded from revegetation programs because they are considered difficult to propagate from seed. This project will build on an existing initial survey of nurseries that propagate indigenous plants for revegetation. Difficult-to-propagate species identified in the survey will be categorised and prioritised. The seed biology of selected species will be reviewed and strategies developed to incorporate these species into nursery production systems. Supervisor: John Delpratt

Seed production in indigenous forbs from cultivated crops.

The cultivation of indigenous herbaceous wildflowers (forbs) for seed production ensures adequate supplies of seed for research and revegetation. However, seed produced in cultivation for such purposes should retain most of the genetic diversity of the wild source population. This project will investigate the breeding system and seed production for selected species of indigenous forbs. There is the potential to include contemporary biotechnology techniques to measure the genetic characteristics of harvested seed. (Note: To allow for seasonal factors, this project may start mid-year or be undertaken on a part-time basis.) Supervisor: John Delpratt

The impact of mowing height and frequency on the establishment and morphology of selected native grasses.

Increasingly, native grasses are being promoted for use as resource-efficient turf in private and public open space and for revegetation. For applications where fire is not appropriate for the management of biomass, periodic mowing will be necessary. This project will investigate the response to mowing height and frequency of one or more commercially available selections of native grasses. Supervisors: John Delpratt & David Aldous

The effect of sowing rate on the establishment and persistence of species within a complex seed mix of native grasses and forbs.

The restoration of species-rich native grasslands may be aided by the direct-sowing of complex seed mixes containing a diverse range of grasses and herbaceous wildflowers (forbs). Initial studies at Burnley have demonstrated that diverse plant communities of grassland species can be established through this technique. This project will investigate the initial establishment and persistence of individual species within a seed mix sown at various rates. Supervisor: John Delpratt

The persistence and regeneration of native perennial forbs in response varying soil-moisture levels during summer.

To regenerate after summer dormancy, many native herbaceous wildflowers (forbs) rely on dormant buds stored near or below ground level. During attempts to re-establish native grassland communities that incorporate a diverse range of forbs, the wildflower component frequently fails to persist into the second growing season. This project will investigate the hypothesis that levels of soil moisture during summer influence the duration of summer dormancy and plant survival. (Note: To allow for seasonal factors, this project will have to be undertaken during consecutive spring, summer and autumn seasons.) Supervisor: John Delpratt