When planning for a revegetation project there are many factors to consider from site preparation to selecting species.
Why are you revegetating? What are you trying to achieve? Are you aiming to improve water quality in your creek? Repair an erosion site? Increase habitat for wildlife? Connect a waterway with your neighbours? Build linkages to larger patches of bush in your area or create stepping stones across the landscape? Enhance a remnant patch of vegetation on your property? Provide a windbreak or shelterbelt for stock? For carbon sequestration? For amenity purposes and shade? Or a combination of these?
Due to the modified and cleared landscape we live in, it may be easier to visualise your project as moving from one state, in its current condition, to an improved vegetative or habitat state? An example could be: changing from an exotic pasture paddock to spaced woodland trees with native shrub patches. Or is it more specific, that you aim to improve the habitat for a targeted group of species in your area i.e. introduce native shrubs for small woodland birds?
Your region may have a broad strategic vegetation plan and provide funding assistance for local projects. Check with Goulburn Broken CMA to see if you qualify for assistance.
You might need to consider bushfire threat and fence placement in the landscape when planning a revegetation project? Are you going to hand plant or direct seed? Sometimes a combination of planting and direct seeding will provide the best results. Alternatively, protecting native vegetation from stock grazing can result in natural regeneration occurring, therefore reducing the amount of revegetation required.
Why do we use indigenous vegetation? Indigenous flora species have evolved and adapted to the Australian landscape for millions of years. Throughout this time, species (both flora and fauna) have adapted to co-exist and survive with each other. Many species have complex symbiotic relationships with other species, and the non-existence of one species can be the demise of another. From the billions of soil biology in the ground to the millions of insect, bird, amphibian, mammal, reptile, crustacean and flora species, all have survived as part of one giant functioning ecosystem.
By using indigenous vegetation, we are using a formula of flora to match the habitat requirements of local fauna species. If we revegetate with non-local native species i.e. Red Flowering Gum from Western Australia or exotic species from overseas, we are introducing competition for local plants, limiting the potential for local species to establish, adapt and evolve into future sustainable populations, and could change the ecosystem balance and species of your local fauna.
Past clearing has removed over 60% of indigenous vegetation in Victoria, resulting in extinctions of mammals, birds, frogs and reptiles with many other species still threatened today, hanging on to their last known habitat. We still have a lot of work to do to sustain a balance in the landscape between sustainable agricultural production and ecosystem diversity and quality. Many farmers and vegetation practitioners today have banded together with the same Landcare ethic to improve this balance in the landscape.
Ecological Vegetation Classes (EVC). Our landscape has a variety of different vegetation types and structures that change across the landscape. Vegetation changes with topography, aspect of slope, soil type, geology, elevation, wetness and rainfall patterns. These site conditions determine where different groups of vegetation survive and flourish. These different groups of vegetation types are better known as Ecological Vegetation Classes or EVC's. This Revegetation Guide helps you to determine the most suitable species for your project site based on the broader goal of rebuilding a functioning landscape.
Threatening Processes- Herbivores can affect the success of your project, and managing herbivores (deer, rabbits, hares, kangaroos, wallabies and red-legged-earth-mite) may need to be considered. Choice of tree guard type might be enough or control programs may need to be considered. Foxes and feral cats can take up residence in your revegetation site and predate on native animals (such as birds, Gliders and Brush Tailed Phascogales). Identify and treat any fox dens and monitor over time, baiting and shooting may be required to reduce populations and work best co-ordinated across a broad area. Noisy Miner birds have proven to outcompete small woodland birds for habitat. Reducing Noisy Miner populations with a permit and creating thick shrub patches for cover can benefit small woodland bird populations recolonising a site.
What Vegetation Structure Type should you have? Vegetation Structure changes across the landscape. Was your site once a Grassland, Woodland, Open Woodland, Forest or Wetland? This will determine what density of what flora structure you revegetate. For example: a true native grassland is often absent of trees altogether, an open woodland will be dominated by native grass and ground layer species with sparse shrubs and open tree canopy. A forest may have a thick tree canopy with thick shrub layer and few native grasses. A Woodland will have a good presence of canopy trees with mixed shrubs and diverse ground layer. Wetlands can be diverse, seasonal herbaceous wetlands may have no canopy species or shrubs, yet many wetland herbs and groundcover species. Perched bog wetlands may have some canopy trees, with medium sized shrubs and wetland specific ground flora. Make sure appropriate vegetation structure is planned for your site, planting canopy trees into an open grassland or seasonal herbaceous wetland will change the future habitat of that area, reducing the opportunity for grassland or wetland dependent species from colonising.
What existing vegetation do you already have on your site? What proportion is native? What proportion is exotic or introduced? Do you have a canopy of local indigenous trees? Do you have any species of local indigenous shrubs? Is there natural regeneration occurring? Do you have native grasses present or other native ground layer species? These are valuable questions that will assist when planning management of a site. If we know what we already have, then our goal could be to create the missing components and structure without destroying existing native species in the process, especially ground layer species.
Site Preparation. Site preparation for revegetation projects is determined by what species are currently present at your site, both native and exotic. All plants are competing for space, light, water and nutrients so if you wish to add indigenous species to the competition, then you need to give your desired plants the advantage.
Determining what ground layer competition you have on your site will help determine what site preparation is required. Assessing ground layer species and cover is best done in spring as most annuals and perennials will be present at this time of the year.
What site groundcover species do you have on your site? What preparation is required?
- 1. Native perennial grass dominated - Herbicide application is not recommended. Slashing lines for direct seeding can reduce biomass for ease of the seeding machine, or cool burning at the right time of year may be considered to reduce biomass. Weed mats for hand planting may be useful.
- 2. Exotic annual grass dominated- Herbicide control by strip spraying for direct seeding or spot spraying for tube stock planting should be considered. Weed mats or mulching around hand planting may be useful for extended weed control.
- 3. Mixed perennial native grass/ exotic grass composition- Selective herbicide control may be required in the exotic grass areas for direct seeding or hand planting, making sure the native grass is not sprayed. Slashing may be more appropriate across a site if the native and exotic grasses are co-existing. Weed matting or mulching when hand planting may be useful.
- 4. Exotic perennial grass dominated- Exotic perennial grass sites dominated by species such as Phalaris or Paspalum require more long term preparation, and this may include multiple herbicide applications to reduce biomass, or cool burning at the right time of year with follow up herbicide control after weeds emerge should reduce biomass and competition. Carefully select hardy dominant revegetation species in these situations, which may outcompete and shade out these grasses in the long term. A denser planting or sowing rate may be required to outcompete these introduced grasses.
Native Vegetation is only one component of habitat for native fauna and insects. To improve the quality of habitat in a site you need a diversity of species and vegetative structures that offer a variety of food sources and homes for species. Things to consider when enhancing habitat of a site are; canopy cover, leaf litter and logs on the ground, hollows of many sizes (in alive and dead trees), and native shrub and ground cover. What is missing from your site? Can you build in (revegetate) the vegetation structure missing from your site such as shrubs or groundcovers? Can you erect nest boxes to provide standing hollows? Can you retain leaf litter and logs on the ground or introduce logs onto the site?
Where do I get indigenous seed and plants?
The main resource for indigenous seed in the Goulburn Broken Catchment is through the Goulburn Broken Indigenous Seedbank, contact 0428 770 030. There are many local nurseries in the Goulburn Broken Catchment that specialise in indigenous local plants, contact your local Landcare Group or GB CMA Officer to identify local indigenous nurseries in your area.