Ecosystem Restoration
When the Mt Oak Community started caring for the land in 1978, it was extremely degraded after years of drought, rabbit plagues and overstocking. There was very little native groundcover and habitat for native fauna was limited. Over the years this has transformed into an environment supporting the many plants and animals shown on the Fauna and Flora pages.
The Mt Oak rehabilitation strategy is concentrated on protection and retention of existing habitat and restoration through natural processes. The removal of threatening processes is usually enough for remnant Australian landscapes to recover, given enough time and a source of seed close by.
While habitat restoration is a process of removing the elements that degraded the environment in the first instance, such as hoofed animal grazing disturbance, the Mt Oak Community Association's primary ongoing rehabilitation tasks are feral animal control and weed control.
Serrated Tussock, African Lovegrass and St John's Wort, along with foxes, wild pigs, feral goats, feral cats and rabbits, are the main obstacles to assisting these nationally depleted temperate grasslands and grassy woodlands to return to something like their former habitat values and levels of biodiversity.
We have gratefully received several grants over the years to assist in weed and feral animal control in the conservation area. Grants have been received from the NSW National Parks and Wildlife Service Private Land Conservation Grants program; NSW Dept of Environment, Climate Change & Water Conservation Partners Program; and the NSW Biodiversity Conservation Trust.
Many hours of voluntary work as well as donations of materials and equipment by MOCA members have enabled the work to be carried out even when external funding wasn’t available.
The Mt Oak rehabilitation strategy is concentrated on protection and retention of existing habitat and restoration through natural processes. The removal of threatening processes is usually enough for remnant Australian landscapes to recover, given enough time and a source of seed close by.
While habitat restoration is a process of removing the elements that degraded the environment in the first instance, such as hoofed animal grazing disturbance, the Mt Oak Community Association's primary ongoing rehabilitation tasks are feral animal control and weed control.
Serrated Tussock, African Lovegrass and St John's Wort, along with foxes, wild pigs, feral goats, feral cats and rabbits, are the main obstacles to assisting these nationally depleted temperate grasslands and grassy woodlands to return to something like their former habitat values and levels of biodiversity.
We have gratefully received several grants over the years to assist in weed and feral animal control in the conservation area. Grants have been received from the NSW National Parks and Wildlife Service Private Land Conservation Grants program; NSW Dept of Environment, Climate Change & Water Conservation Partners Program; and the NSW Biodiversity Conservation Trust.
Many hours of voluntary work as well as donations of materials and equipment by MOCA members have enabled the work to be carried out even when external funding wasn’t available.
Ecosystem Restoration Techniques
A. SEED DISPERSAL
Allowing natural regeneration through seed dispersal from existing plants on site is the most efficient method. However, as there is heavy grazing pressure in some areas from kangaroos, other macropods, and goats, we have fenced off plots of natives to act as a seed source for natural revegetation. Exclusion fencing has been erected in Warm Corners for red-leg grass and in the community area for native sorghum and kangaroo grass.
Allowing natural regeneration through seed dispersal from existing plants on site is the most efficient method. However, as there is heavy grazing pressure in some areas from kangaroos, other macropods, and goats, we have fenced off plots of natives to act as a seed source for natural revegetation. Exclusion fencing has been erected in Warm Corners for red-leg grass and in the community area for native sorghum and kangaroo grass.
MOCA members have collected seed from Mt Oak, propagated it, and then planted out the seedlings. This has been most successful with the Callitris, some of which are now planted around the entry gate and in the community area.
B. REVEGETATION
Revegetation by planting seedlings on a large scale is not feasible or desirable at Mt Oak due to limitations of labour, finances and water.
In the early days of the community thousands of trees were planted around the community area to stabilise the slopes and reduce erosion. These plantings were mainly of useful plants, anything that would grow in the degraded soil and drought conditions. Some of these original plantings are being removed now as they have become weeds or have the potential to become weeds.
In recent years there have been some native tree plantings on the edges of the front creek and around the community area, to re-introduce native plants to heavily degraded areas.
Revegetation by planting seedlings on a large scale is not feasible or desirable at Mt Oak due to limitations of labour, finances and water.
In the early days of the community thousands of trees were planted around the community area to stabilise the slopes and reduce erosion. These plantings were mainly of useful plants, anything that would grow in the degraded soil and drought conditions. Some of these original plantings are being removed now as they have become weeds or have the potential to become weeds.
In recent years there have been some native tree plantings on the edges of the front creek and around the community area, to re-introduce native plants to heavily degraded areas.
C.WEED CONTROL
Weeds are a problem when they are present in dense enough infestations that they prevent the native vegetation from regenerating. They compete for scarce water, nutrients and light. Weeds have many other impacts on the ecosystems including genetic pollution and hybridising with native species. Some are poisonous to native plants and others transform the ecosystem by using water in different seasons.
Our weed control techniques have included biological control, hand removal, traditional burns, slashing and chemical control.
1. Biological control
Biological control would be our preferred method of dealing with invasive plants. However, the short breeding season and unreliable rainfall at Mt Oak make it difficult to establish the control agents. We mostly rely on natural spread of the agents, but have previously released St John’s Wort Mite, Chrysolina beetle and the Horehound Clearwing Moth.
In 2013 we hosted a workshop by Barry Sampson on biocontrol and integrated weed management. Many local farmers and residents attended a workshop in the Bredbo Hall and then came to Mt Oak to watch the release of the biocontrol agents.
Weeds are a problem when they are present in dense enough infestations that they prevent the native vegetation from regenerating. They compete for scarce water, nutrients and light. Weeds have many other impacts on the ecosystems including genetic pollution and hybridising with native species. Some are poisonous to native plants and others transform the ecosystem by using water in different seasons.
Our weed control techniques have included biological control, hand removal, traditional burns, slashing and chemical control.
1. Biological control
Biological control would be our preferred method of dealing with invasive plants. However, the short breeding season and unreliable rainfall at Mt Oak make it difficult to establish the control agents. We mostly rely on natural spread of the agents, but have previously released St John’s Wort Mite, Chrysolina beetle and the Horehound Clearwing Moth.
In 2013 we hosted a workshop by Barry Sampson on biocontrol and integrated weed management. Many local farmers and residents attended a workshop in the Bredbo Hall and then came to Mt Oak to watch the release of the biocontrol agents.
The following table details the biological control agents known to be present or to have been released at Mount Oak. In general, current weed populations reflect ongoing impacts of biological control: little can be done to enhance the effectiveness of agents already well-established.
|
Weed |
Agent |
Status |
|
|
Common Name |
Scientific Name |
||
|
St Johns Wort |
Hypericum Stem Aphis |
Aphis chloris |
on a few scattered plants |
|
St John's Wort Leaf Beetle |
Chrysolina quadrigemina |
Very abundant some years |
|
|
St John's Wort Mite |
Aculus hyperici |
Released, not known to be established |
|
|
Blackberry |
Blackberry Leaf rust |
Phragmidium violaceum |
Present, little impact |
|
Horehound |
Horehound Plume Moth |
Wheeleria spilodactyla |
Abundant |
|
Horehound Clearwing Moth |
Chamaesphecia mysiniformis |
Released, not known to be established |
|
|
Spear Thistle |
Spear Thistle Gall Fly |
Urophora stylata |
Abundant, highly damaging |
|
Thistle Receptacle Weevil |
Rhinocyllus conicus |
Common, damaging |
|
|
Slender Thistle |
Slender Thistle Rust |
Puccinia carduipycnocephali |
Established, damaging |
|
Nodding Thistle |
Thistle Receptacle Weevil |
Rhinocyllus conicus |
Established |
|
Nodding Thistle Gall Fly |
Urophora sostitialis |
Established |
|
|
Scotch Thistle |
Onopordum Stem-boring weevil |
Lixus cardui |
Established, common |
|
Onopordum Seedhead Weevil |
Larinus latus |
Established, abundant |
|
|
Skeleton Weed |
Skeleton weed Rust Fungus |
Puccinia chondrillae |
Present |
|
Chondrilla Gall Mite |
Aceria chondrillae |
Common, damaging |
|
|
Vipers Bugloss |
Patterson's Curse Crown Weevil |
Mogulones laryatus |
Common, damaging |
|
Paterson's Curse Flower Beetle |
Meligethes planiusculus |
Common |
|
|
Patterson's Curse Leaf-mining Moth, Echium Leaf-miner |
Dialectica scalariella |
Common |
|
|
Patterson's Curse Stem-boring Beetle |
Phytoecia coerulescens |
one adult seen |
2. Hand removal
Some weeds are currently minor problems, in terms of the area covered, and are hand weeded to reduce their spread. Verbena, fleabane, thistles, and woolly mullein are some of the weeds in this category. Other more serious weeds are also hand weeded where there are isolated plants, and in frequently used areas like the community shed and around the campsite. Weed tree seedlings are also hand weeded while they are small enough.
Weeds are placed in piles to reduce the spread of seeds and then burnt in cooking fires or heating stoves if feasible.
3.Traditional burn
In June 2018 a cultural burn was done in the front paddock to reduce the African Lovegrass and St. John's Wort density. This was undertaken by Rod Mason, Ngarigo elder, with Wally Bell, Ngunnawal elder, the local Rural Fire Service, and local community groups.
In June 2018 a cultural burn was done in the front paddock to reduce the African Lovegrass and St. John's Wort density. This was undertaken by Rod Mason, Ngarigo elder, with Wally Bell, Ngunnawal elder, the local Rural Fire Service, and local community groups.
4.Slashing
We have trialed slashing as a way to reduce the vegetative mass of African Lovegrass, and seed spread, along the road corridor. We have also used slashing to reduce the biomass of serrated tussock and contain it's seed production to allow for regeneration or direct seeding of species such as red leg grass. This method prevents the creation of large areas of bare ground resulting from broadscale foliar spraying, which inevitably leads to reinvasion by weeds.
We have trialed slashing as a way to reduce the vegetative mass of African Lovegrass, and seed spread, along the road corridor. We have also used slashing to reduce the biomass of serrated tussock and contain it's seed production to allow for regeneration or direct seeding of species such as red leg grass. This method prevents the creation of large areas of bare ground resulting from broadscale foliar spraying, which inevitably leads to reinvasion by weeds.
5.Chemical Control
Chemical control is used as a last resort where weed infestations are extensive and dense. We have aimed to contain weed spread into and out of the site by slashing and spraying along the fence lines and the road edges.
Chemical application has been by careful spot spraying to preserve any native plants that are present. Detailed records are kept of the areas treated and the rates applied. We have used backpack sprayers in more inaccessible areas and spray units for areas where hoses and vehicles can reach.
Some weed areas on the mountains are too difficult even for backpack spraying so we have trialled using granulated chemical control there, especially for serrated tussock. We have also participated in a district-wide helicopter spraying program to reach the mountain tops, again targeting serrated tussock.
For woody weeds and weed trees, we have applied chemical using cut and paint or frill/drill and fill techniques.
Chemical control is used as a last resort where weed infestations are extensive and dense. We have aimed to contain weed spread into and out of the site by slashing and spraying along the fence lines and the road edges.
Chemical application has been by careful spot spraying to preserve any native plants that are present. Detailed records are kept of the areas treated and the rates applied. We have used backpack sprayers in more inaccessible areas and spray units for areas where hoses and vehicles can reach.
Some weed areas on the mountains are too difficult even for backpack spraying so we have trialled using granulated chemical control there, especially for serrated tussock. We have also participated in a district-wide helicopter spraying program to reach the mountain tops, again targeting serrated tussock.
For woody weeds and weed trees, we have applied chemical using cut and paint or frill/drill and fill techniques.
Weeds and their treatment
Serrated tussock (Nasella trichotoma) is a grass which forms dense clumps in many areas around the land and is one of our major target weeds. As described above, it has been treated with spot spray, helicopter spray, and granules.
African lovegrass (Eragrostis curvula) is widespread and dense especially in any cleared or disturbed areas. It is being treated with spot spraying, and slashing.
St. John’s Wort (Hypericum perforatum) is a useful medicinal herb in small amounts and we have set aside a small area for harvesting it. However, it covers many hectares of Mt. Oak, where it out-competes native flora. It is treated with spot spray and hand removal of isolated infestations.
Horehound (Marrubium vulgare) although not a major weed on Mt Oak, is present in disturbed places like old rabbit warrens. Isolated patches have been weeded by hand. Whenever patches are discovered during spot spraying other weeds, it is treated at the same time. A biocontrol agent is also active in some patches.
Viper’s bugloss (Echium vulgare) and Paterson’s Curse (Echium plantagineum)
The amount of these weeds has reduced in the last decade, possibly due to the removal of commercial European beehives which were pollinating these blue-flowered weeds and encouraging seed set. Isolated patches have been weeded by hand. A biocontrol agent is now also active in most patches.
Briar Rose (Rosa rubignosa) is widespread in the grassy areas of the site. Some plants are left as refuges for small birds, but those along the drain lines have been treated with cut and paint.
Willows (Salix spp). Female plants were targeted with frill and fill. Some are left along the river as they help to stabilise the banks.
Black Locust (Robinia pseudoacacia) These were introduced as nitrogen- fixers but have set seed as they matured and are in danger of spreading. The trees are being cut down or treated with drill and fill.
Wild Cherry (Prunus avium? / Prunus mahaleb?) Probably introduced as rootstocks, the seed has been spread by foxes and birds. Seedlings are hand removed and more mature plants are cut and painted or drill and fill on larger stems.
Hawthorn (Crataegus monogyna) and Orange Firethorn (Pyracantha angustifolia). These two small trees have been spread by birds. Isolated plants are cut and painted.
Blackberry (Rubus fruticosus). It has been treated with spot spray followed by cut and paint on any regrowth. Some patches were successfully treated with cut and paint only.
Serrated tussock (Nasella trichotoma) is a grass which forms dense clumps in many areas around the land and is one of our major target weeds. As described above, it has been treated with spot spray, helicopter spray, and granules.
African lovegrass (Eragrostis curvula) is widespread and dense especially in any cleared or disturbed areas. It is being treated with spot spraying, and slashing.
St. John’s Wort (Hypericum perforatum) is a useful medicinal herb in small amounts and we have set aside a small area for harvesting it. However, it covers many hectares of Mt. Oak, where it out-competes native flora. It is treated with spot spray and hand removal of isolated infestations.
Horehound (Marrubium vulgare) although not a major weed on Mt Oak, is present in disturbed places like old rabbit warrens. Isolated patches have been weeded by hand. Whenever patches are discovered during spot spraying other weeds, it is treated at the same time. A biocontrol agent is also active in some patches.
Viper’s bugloss (Echium vulgare) and Paterson’s Curse (Echium plantagineum)
The amount of these weeds has reduced in the last decade, possibly due to the removal of commercial European beehives which were pollinating these blue-flowered weeds and encouraging seed set. Isolated patches have been weeded by hand. A biocontrol agent is now also active in most patches.
Briar Rose (Rosa rubignosa) is widespread in the grassy areas of the site. Some plants are left as refuges for small birds, but those along the drain lines have been treated with cut and paint.
Willows (Salix spp). Female plants were targeted with frill and fill. Some are left along the river as they help to stabilise the banks.
Black Locust (Robinia pseudoacacia) These were introduced as nitrogen- fixers but have set seed as they matured and are in danger of spreading. The trees are being cut down or treated with drill and fill.
Wild Cherry (Prunus avium? / Prunus mahaleb?) Probably introduced as rootstocks, the seed has been spread by foxes and birds. Seedlings are hand removed and more mature plants are cut and painted or drill and fill on larger stems.
Hawthorn (Crataegus monogyna) and Orange Firethorn (Pyracantha angustifolia). These two small trees have been spread by birds. Isolated plants are cut and painted.
Blackberry (Rubus fruticosus). It has been treated with spot spray followed by cut and paint on any regrowth. Some patches were successfully treated with cut and paint only.
D. FERAL ANIMAL CONTROL
Feral animals compete with native animals for food and water. Goats and deer also cause physical damage by browsing on seedlings and stripping bark from some plants. Pigs disturb the soil, increasing soil erosion. Cats hunt birds and small animals. Rabbits eat young plants and disturb the soil with their burrows.
The main techniques of feral animal control used at Mt. Oak have been trapping, shooting and exclusion fencing.
Trapping has been used to remove or relocate pigs, cats, rabbits, and rats. We hire professional shooters to reduce the numbers of pigs, goats, deer, and foxes
There are sometimes feral sheep on Mt Oak, escaped from neighbouring properties. Feral sheep spread weeds, damage seedlings and compete with native animals for grazing. A mob of diseased feral sheep were culled in 2024. Maintaining fences is an important part of excluding them and is an ongoing challenge.
Feral animals compete with native animals for food and water. Goats and deer also cause physical damage by browsing on seedlings and stripping bark from some plants. Pigs disturb the soil, increasing soil erosion. Cats hunt birds and small animals. Rabbits eat young plants and disturb the soil with their burrows.
The main techniques of feral animal control used at Mt. Oak have been trapping, shooting and exclusion fencing.
Trapping has been used to remove or relocate pigs, cats, rabbits, and rats. We hire professional shooters to reduce the numbers of pigs, goats, deer, and foxes
There are sometimes feral sheep on Mt Oak, escaped from neighbouring properties. Feral sheep spread weeds, damage seedlings and compete with native animals for grazing. A mob of diseased feral sheep were culled in 2024. Maintaining fences is an important part of excluding them and is an ongoing challenge.
E. EROSION CONTROL
The soils at Mt. Oak are mostly highly erodible decomposed granite. The Bredbo district was notorious during the twentieth century for extreme gully erosion resulting from the removal of vegetation by humans, drought and rabbits.
In the early years of the community, the land was suffering from drought and rabbit infestation with very little ground cover. There were some large active erosion gullies, up to 3m deep in places. A number of different barriers were created in the gullies to slow down the storm water flow. These included short fences, tyre walls, and even crushed car bodies. The main erosion gully near the community house is almost stabilised, with grass covered sides and a flat base. The old barriers have been covered in silt in many places, so have been successful in slowing the water flow.
The soils at Mt. Oak are mostly highly erodible decomposed granite. The Bredbo district was notorious during the twentieth century for extreme gully erosion resulting from the removal of vegetation by humans, drought and rabbits.
In the early years of the community, the land was suffering from drought and rabbit infestation with very little ground cover. There were some large active erosion gullies, up to 3m deep in places. A number of different barriers were created in the gullies to slow down the storm water flow. These included short fences, tyre walls, and even crushed car bodies. The main erosion gully near the community house is almost stabilised, with grass covered sides and a flat base. The old barriers have been covered in silt in many places, so have been successful in slowing the water flow.
During the first decade of the community many bare areas in the settlement area were planted with trees in a herringbone pattern and watered by (now defunct) drip irrigation lines. Many of those trees are now mature and the bare soil has become covered in grasses and wildflowers, further stabilising the soil erosion.
Runoff from the roads and tracks is a major current cause of soil erosion. Hence the importance of driving on the existing tracks when visiting. Some parts of the road have been realigned to avoid steep slopes and it is gradually being repaired with take-off drains to reduce the water flow and erosion.
Runoff from the roads and tracks is a major current cause of soil erosion. Hence the importance of driving on the existing tracks when visiting. Some parts of the road have been realigned to avoid steep slopes and it is gradually being repaired with take-off drains to reduce the water flow and erosion.
F. MONITORING AND RECORDING
As part of planning our work we monitor weed infestations and feral animal populations so we can prioritise our efforts. We have established photo points and vegetation monitoring quadrats in the Conservation Area so that we can record the improvements in biodiversity over time.
There have also been formal fauna surveys and ongoing collection and observation of flora and insect populations. Bird surveys are undertaken regularly by a local bird group.
As part of planning our work we monitor weed infestations and feral animal populations so we can prioritise our efforts. We have established photo points and vegetation monitoring quadrats in the Conservation Area so that we can record the improvements in biodiversity over time.
There have also been formal fauna surveys and ongoing collection and observation of flora and insect populations. Bird surveys are undertaken regularly by a local bird group.
Land management areas used in planning our work before GPS and online mapping resources were available
The work continues
The land has been transformed from a barren landscape with a few struggling trees, to the rich biodiversity today. However. weeds and feral animals are still having big impacts and we have a Weeds Working Group as well as one dealing with the feral animals. Please contact us if you’d like to help with this worthwhile project.
The land has been transformed from a barren landscape with a few struggling trees, to the rich biodiversity today. However. weeds and feral animals are still having big impacts and we have a Weeds Working Group as well as one dealing with the feral animals. Please contact us if you’d like to help with this worthwhile project.
