Restoring native vegetation: regenerate or re-vegetate? This note provides an overview of the two basic approaches to restoring and expanding native vegetation and wildlife habitat, and discusses where and when they are best used.
Assisted natural regeneration involves creating the right conditions for damaged ecosystems (communities of plants and animals) to bounce back. It usually includes managing threats such as weeds and grazing, and applying triggers such as fire to stimulate regeneration. This approach is often called ‘bush regeneration’.
Re-vegetation is used where the ecosystem is too damaged to regenerate naturally and the appropriate plants have to be reintroduced, for example by planting or direct seeding.
The choice depends mainly on the health of the vegetation, particularly its capacity to re-sprout or germinate from seed after the causes of degradation have been removed. Assisted natural regeneration can be the most cost effective and ecologically sound approach because it retains the character and complexity of the local ecosystems. Planting should generally be avoided where natural regeneration is possible.
Vegetation condition usually varies across a property or even within a small patch, so both approaches may be used alongside each other.
Priorities for sustainable vegetation management
FIRST — retain existing native vegetation (avoid clearing). Native vegetation can help protect a site from land degradation, and provide free services such as shade, shelter, habitat for predators of pests, and habitat for pollinators.
THEN — protect native vegetation from degradation (manage threats). On a farm the most important strategy is to fence off native vegetation from adjoining paddocks. This does not necessarily mean locking it up. It does mean that management can be tailored to the needs of the vegetation as well as to production goals. Even fencing off a small area downwind of a large old paddock tree may give good tree regeneration quickly, and keep trees in the landscape for future generations.
LATER — actively manage degraded vegetation (restore, expand and link). In fenced remnant areas it may be necessary to control weeds and manage grazing and even apply other treatments to expand the regeneration. In long-cleared areas, planting or direct seeding can be necessary to link native vegetation patches. However, beware of ill-considered actions. A ‘do nothing and watch approach’ is often best at first, until it is clear what the threats are and how best to deal with them.
Re-vegetation is undertaken for a number of reasons, including:
to establish wildlife habitat;
to establish buffers to protect native bush;
to link patches of remnant bush;
to establish shelter belts for stock or crop protection;
to establish windbreaks for erosion control;
to control run-off;
to manage problems such as salinity and water logging;
to establish commercial tree plantations or farm forestry.
It is much better to conserve your existing remnant bush and manage it well than try to reestablish it after it has been cleared. It cannot be emphasised enough that natural regeneration is the cheapest and most effective method of re-establishing or rehabilitating the bush on your property. Do not start thinking about any re-vegetation projects until you are sure that natural regeneration is not an option.
PLANTING TECHNIQUES Planting may be done at any time in the tropical region however better growth and survival rates are achieved over the traditional wetters months of spring and summer and early autumn. Preparation
Remove the grass for at least a metre in diametre for around the trunk for specimen trees
Turn over the soil thoroughly to aerate, also removing any weeds and any turf.
The planting hole should be twice the width and at least 150mm deeper than the pot
Use compost or organic fertiliser mixed with the excavated soil
Phosphorus intolerant species such Grevillia and Banksia require fertiliser low in phosphorus (less than P4)
Slow release fertilisers can be used on rain forest and most other native species.
Moisten he root ball by soaking in a bucket of water
Fill the hole with water and allow it to drain into the soil
Carefully remove the plant for the pot, teasing out any roots if the plant is severely pot bound
Place the root ball so that the top is level with the surrounding soil.
Back fill the excavated soil whilst gently tamping down down around the sides to expel any air pockets.
Form a slight basin from the centre of the hole to the edge ensuring that no excess soil is placed against the trunk.
Generally staking of trees should not be undertaken unless it is to support an advanced tree or to protect specimen trees from damage.
Mulch is important to prevent loss of soil moisture and to keep young surface roots cool as well as helping suppress weed growth. Additional organic fertiliser should be incorporated to prevent nitrogen draw down when using bark mulches.
Correct plant selection for the location is desirable and will reduce maintenance. Tip pruning promotes good branching, dense growth and increased flowering for many shrubs while pruning of trees will assist in the desired shape of the canopy.
Pests and Disease
Insect attack on your plants should be treated as soon as the infestation becomes apparent.. Correct identification of the insect or disease is essential to ensure the correct application or treatment used. Organic pesticides should always be used where possible.
If you are considering any planting projects for your farm or block then please download this booklet to help you get more of an idea