Some of the information for this article has come from the Invasive Species Council (ISC) that has led the campaign to deal with one of the major sources of the invasive weed problem, escaped garden plants. Despite their threat, most invasive plants in Australia are not regulated and continue to be planted and introduced to new areas.

Australia's national weeds strategy was introduced in 1997 to provide a national framework for state, territory, regional and local governments to manage weed problems. However, it wasn't until June 2024 that there was an agreement to establish a specific action plan to address escaped garden plants after it was refused twice in 2009 and 2014. This time the federal Minister for Environment Tanya Plibersek, supported by state environment ministers, has agreed to develop a national Threat Abatement Plan to tackle escaped garden plants and aquatic weeds.

The issue of weed invasion from escaped garden plants was listed as a key threatening process under the EPBC Act in 2010. The governments’ argument up until now has been that the biosecurity laws were adequate to deal with the problem but their focus is on the importation of new plants not the problem that already exists from invasive weeds.

Extent of the problem

The ISC outlines the extent of the issue of weeds in NSW in the following points:

• More than $50 million of public money (about half from state government), supplemented by a large voluntary expenditure and effort, is currently being spent on weed control in NSW.
• However, the effort to control weeds is not keeping up with the rapid spread of weeds, and the NSW government has conceded it is unlikely to meet its 2015 target of ‘a reduction in the impact of invasive species’.
• Weeds imperil more than 40% of NSW threatened species (mostly plants) and about 90% of endangered ecological communities.
• 340 environmental weeds are recognised in NSW. Most were deliberately introduced as garden and pasture plants.
• There are already more than 30,000 exotic plant species in Australia (mostly cultivated), and more than 99% can be freely sold and planted in NSW. This includes many thousands of new potential weeds that can be introduced into NSW without risk assessment.
• Taking action on weeds creates substantial environmental, social and economic advantages.
• Weed management is one of the biggest gaps in NSW environmental laws and policies.

Plan for action

The ISC advocates a much stronger focus on prevention as many of Australia’s weeds are in a very early stage of invasion or not yet spreading. They're weeds that might have just started to establish locally, but we now understand they've got huge potential to explode across the landscape.

To do this, the ISC is asking each state and territory to require all new introductions into their states to pass a risk assessment. Only plants on a ‘safe list’ would be allowed to be sold or moved between states and territories. Some species already well entrenched would also be on this permitted list. This reversing the current practice where plants are not assessed until after they have become an invasion risk.

The Centre for Invasive Species Solutions — a not-for-profit collaboration between federal and state governments, CSIRO, and other member organisations — assesses the potential for a plant species to become invasive and recommends whether they are declared a noxious weed.

Stop the sale of existing and potential weeds

We need an agreement to assess the 30,000-plus plants we've got here and to identify which ones are known weeds, and which ones could become serious weeds, and to then ban and restrict their sale. One example is Spanish Moss that is termed to be a sleeper weed. As climate becomes warmer and wetter it is spreading and becoming more prolific.

At least three-quarters of weeds established in the Australian environment have come from escaped garden plants. Many of these invasives are pretty to look at, very hardy and don't need a lot of water. What makes them attractive for nurseries are the same things which makes them problematic as weeds. Gardeners looking for an easy fix, they are planting agapanthus for example, and they are spreading it unknowingly. The Blue Mountains is an area where it is a particular problem.

The ABC last year reported retail giant Bunnings was selling varieties of Gazania — an invasive flowering weed native to southern Africa — despite its status as a declared weed in Victoria (all subspecies), Queensland, Tasmania and New South Wales (Gazania rigens).

In the past 12 months, the ISC has identified a range of weeds for sale at nurseries, including mock orange (Murraya paniculata), duranta (Duranta erecta), mother-in-law's tongue (Sansevieria trifasciata), Japanese honeysuckle (Lonicera japonica) and English ivy (Hedera helix).

Current state government weed management framework in urban areas

At the state government level, weeds are managed under the Biosecurity Act 2015. This establishes a list of ‘priority weeds’ that are banned from being sold in NSW or certain regions of NSW. This does not mean that they have to be eradicated. In fact some are so well entrenched that removal is too costly or even feasible. This does not mean that we shouldn’t try to prevent the spread as much as possible.

Click here for a description of the process of risk management.

Management categories for priority weeds

Class 1 State Prohibited Weeds
Must be eradicated from the land and the land must be kept free of the plant, eg Boneseed, Hawkweed.

Class 2 Regionally Prohibited Weeds
Must be eradicated from the land and the land must be kept free of the plant, eg African Olive in the Blue Mountains.

Class 3 Regionally Controlled Weeds
Must be fully and continuously suppressed and destroyed and where applicable the plant must not be sold, propagated or knowingly distributed.

Class 4 Locally Controlled Weeds
For example blackberry, lantana, morning glory, Madeira vine (Anredera)

Class 5 Restricted Plants
Not yet established in NSW, must not be sold, propagated or knowingly distributed

Main weed management processes

• The NSW Weed Action Program that provides grants to local control authorities for weeds to enable them to undertake activities that focus on the prevention of priority weeds and their management.
• Regional Strategic Weed Management Plans that guide weed management in each of the 11 Local Land Services regions in New South Wales. These plans prioritise activities, clarify expectations and help guide investment to lead to more coordinated, efficient and effective weed management.

There are regional weed committees in each local land region that work on the strategic management plans. Within each region there are subgroups. For example, the Greater Sydney region has three subgroups under the Sydney Weeds Network.

Local council obligations

Apart from a state classifications that focus on high priority weeds, each local council has to establish a weed risk assessment process. This is used to set priorities for management on council land. There is a detailed rating system that considers factors like density, ability to spread and reproduce, economics of removal and geographical spread of infestation.

Local councils are authorised to issue a biosecurity directive to the owner or occupier of a property where priority weeds are sighted or reported. When a property owner or occupier is issued with a biosecurity directive, they have a legal obligation to control the weeds in the manner described by the risk rating, or as instructed by council in the biosecurity directive.

We all have an obligation to be on the lookout for biosecurity risks. They can be reported to your local council directly or reported on the Snap, Send, Solve app.

Key information can be found on the NSW Weedwise website or app.

Status of Spanish Moss

The current regional strategic weed management plan for Greater Sydney is due for renewal in 2027. Unfortunately, Spanish Moss has a low priority in our local council areas. We hope that evidence and consideration of the impacts of Spanish Moss will lead to its banning from sale under the new plan.

STEP and other local community groups are working with our local councils to raise awareness of this rapidly emerging problem.

The NSW Office of Local Government is currently reviewing the Companion Animals Act 1998 (yes it is that old) and asking for feedback from the community on a discussion paper on possible amendments and the closing date is 4 May.

The key aim of the review is to ensure that the updated legislation improves responsible pet ownership, ensuring the well-being of pets and the safety of our communities.

It is not only the community that is affected by companion animals. This is an opportunity to act on the huge number of wildlife deaths caused by feral cats and domestic cats that are allowed to roam.

Every year about 66 million native mammals, frogs, reptiles and birds are killed by roaming pet cats just in Greater Sydney. We need a cultural change to stop this and that starts with empowering councils to bring in clear cat containment rules.

The current laws actually prevent local councils from mandating that cats are contained. Cat containment will make a huge difference to the protection of local wildlife. It will also be a win for cat owners. Wandering cats are at risk of injury. According to the Invasive Species Council there is evidence pet cats kept responsibly at home can live up to 10 years longer than if they are free roaming.

Outdated laws in NSW prevent councils from acting. This is a stark contrast to Victoria which has empowered councils to introduce containment rules, and over half have done so. The ACT has also mandated cat containment territory wide.

The changes to the Act that are needed include:

• allow councils to bring in and enforce cat containment rules that apply 24/7
• mandatory microchipping and desexing for all cats by 4 months or age with exceptions for licensed breeders
• assistance for pet cat owners that can’t afford desexing
• state-wide grant program to support councils in implementing these changes
• develop state-wide education programs

The Invasive Species Council is leading the campaign to amend the Act. Find out more about the problem of roaming cats and solutions.

They would like at least 20,000 submissions to convince the government that there is strong support for these changes.

Polling indicates that only a small proportion of people would like their cats to continue to roam. However there is a laissez-faire attitude as about 70% of owners allow their cats to roam although a smaller number allow them to roam at night.

Dog ownership

The review also covers management of pet dogs. Owners allowing their dogs to wander in bushland areas is a perennial problem. They are not allowed to be off-leash in the street. This also applies to other public areas like bushland. The smell of dogs deters animals like birds from entering areas where there may be a nest or is an important foraging area. They also attack native animals like water dragons and wallabies that are seen in our local bushland.

Councils fail to enforce dog regulations. There are simply not enough wardens to enforce them so that owners don’t perceive that there is a risk in allowing their dog to roam. The state government must provide more of a lead in this issue with funding for more council resources.

It is very concerning that Australia does not have a long term population strategy. The current housing crisis is a symptom of this situation. We are struggling to find ways to rapidly make up for the housing and infrastructure needs from past growth. But there is no letup in the policy of high immigration that has applied in the 21st century.

Governments claim that population growth is good for the country. The headline measure used is increases in GDP but, in fact on a per capita basis, GDP is actually falling. ABS figures of real GDP growth per capita are negative in calendar 2024 (−0.7%) and 2023 (−1.0%) while the headline figures are 1.3% and 1.5% respectively.

It appears that the housing situation is only going to get worse as government policies are to continue with no prospect of the population growth rate slowing let alone stabilising. How can this happen without continuing degradation of our unique natural world? We have a responsibility to preserve our biodiversity. Tough decisions are required to actually implement the government policies to be ‘nature positive’. The current population growth policies are making this impossible and, sadly, promised changes to our biodiversity laws are still being delayed.

Both of the major parties quote targets for permanent migration but these ignore temporary migration where there appears to be no means of limiting numbers.

Outline of recent experience

At 30 June 2024 Australia’s population was measured at 27.2 million. The table below summarises the changes over the 21st century. The fall in migration during COVID has been made up by a large increase over the past two years.

Net overseas migration (NOM) has been over 200,000 pa since 2004 compared with less than 80,000 pa during the decade to June 2000.

The measure of population is technical. The figures above of NOM only allow for people who have been resident in Australia for at least 12 months out of the past 16 months. In the case of departures, it subtracts residents who have been absent for at least 12 months over the past 16 months.

Many temporary residents are not counted

The actual number of people living in Australia is considerably greater because of temporary residents who have not been here long enough to be counted in NOM. It is not possible to separate out temporary residents that are counted in NOM and those that are not. Many of those counted as residents would be New Zealanders who have been here for many years. By a Trans-Tasman Agreement they can come and go and are not counted as permanent residents.

The total number of temporary residents at 30 June 2024 was 2.338 million. This number has increased from 1.755 million at 30 June 2017. The number of New Zealanders living in Australia is usually in the range of 600,000 to 700,000 so they have not made a significant contribution to the increase.

If the number of other temporary residents who have been here for less than a year are added to the official figure the number of people currently living in the country is likely to be well over 28 million.

The main categories of temporary residents are students and workers (skilled and backpackers). Many of these people can eventually be granted permanent residency. The number of students at 30 June 2024 was 608,000 and workers under various visas numbered about 1 million. With pressure from universities and employers the government is reluctant to bring these numbers down.

In theory students are only in Australia for the length of their course but there are ways for them to extend their stay and may be granted permanent residency.

Growth projections out to 2035

The government does produce population projections. They are used for planning and budgetary purposes in the medium term. The most significant factor in these projections is NOM as our natural increase rate (births minus deaths) is reducing steadily over time. Given the lack of control of temporary migration these projections will be underestimates.

There is no contemplation of a reduction in NOM

The projection of NOM used for budgetary purposes over the next 2 years is 260,000, more than the average experience this century. But this estimate has already been exceeded in the current year by 60,000. The longer term assumption is 235,000 pa but the ability to control this figure is problematic.

The Centre for Population that comes under Federal Treasury projects that the population at 30 June 2035 will be 31.3 million. That’s another 4 million people to be accommodated in just 10 years.

Is this a responsible policy to expect to accommodate an extra 4 million people with their needs for schools, hospitals, transport, water etc? What will our cities be like?

We already are getting a picture of the changes that will need to be made to our cities with the NSW government policies for wholesale rezoning to higher density that will change the character of our suburbs and cities with great environmental impact such as loss of tree canopy.

The planning controls are much too weak to ensure that our streetscapes and building design will maintain a desirable quality of life. In our early days streets were wide enough to have room for shady trees. Just look at Darlinghurst or Kirribilli. Instead, the higher density plans being implemented by the NSW government will be creating heat islands.

We are still playing catch-up for inadequate housing construction over the past several years. The housing accord made by the Australian and state governments aims to build another 1.2 million homes over the next 5 years. Even if that can be achieved it will clearly be inadequate.

The demand for resources to cater for this increase is evident in the sad statistics about our biodiversity loss from land clearing. It seems this will only get worse as the paradigm of growth continues to dominate.

Control of numbers of temporary residents

One major problem is that we don’t have control over temporary migration. Governments over the years claim they are managing the migration numbers but this only applies to migrants granted permanent visas. This annual number was 190,000 for 2023-24 and will reduce to 185,000 for 2024-25 – big deal! The Coalition have indicated that they will reduce the permanent intake to 140,000 for the next two years and has provided very confusing messages about temporary migration. The only definite statement is a reduction in the number of permanent refugee visas from 20,000 to 13,750, a mean decision.

There is a large backlog of partner visa applications where approvals are counted in the permanent visa total. Under the Migration Act there is no scope to reduce the number of these permanent visa grants.

Students

In December 2023 the Labor government announced it intended to restrict the number of student visas in the interest of taking pressure off the housing crisis. But under the current legislation this is difficult. The response was a backlash from the overseas education industry. A reduction also depends on students returning home at completion of their course over which the government has little control. There are several means for students to stay on with, for example, a graduate visa. We are back to the previous expected cap of 270,000 student entries in 2025.

Conclusion

While the government is trying to reduce net migration, the demands for skilled workers and partner visas and universities are making this impossible. Even the projected numbers of 235,000 used in government forecasting seem to be optimistic. The Coalition ideas of reducing migration seem to be impractical.

Reducing growth is hard to do.

Having ramped up the level of immigration it will be hard to reduce it back to reasonable levels. The high level of immigration activity creates a vicious circle – more people > need more houses > need more workers, and so on.

If migration slows down the reduction in the number of new houses, schools etc to be built will be more manageable. A lot of workers will have to find alternative employment. Cutting back is hard to do but the longer we wait the harder it will be to make the change. But it has to be done. We cannot keep growing forever.

Does William the Conqueror has a lot to answer for? Well he quite possibly does – as author Guy Shrubsole points out early in this rich and complex book, the Norman invasion of Britain in 1066 was followed by newly crowned King William distributing vast land grants to his 200 or so supporting barons. Many of these land subdivisions have survived to this day through multiple descendants and land sales. The landowning and moneyed aristocracy further tightened their grip down the ages through the Scottish Highland Clearances of the 18th and 19th centuries and the enclosure or ‘inclosure’ of common land in England – each taking away the rights of ordinary folk to access and use it.

But what has this got to do with Australia? Well the colonial occupation of this continent could also be viewed as a Norman invasion wherein their gene-compromised descendants invaded and took over land with little regard for the native inhabitants. This was enhanced down the track by many measures and events such as the Robertson Land Acts of the 1860s that overturned the squattocracy in NSW: the squatters having already overridden rightful First Nations ownership.

However it’s the British land ownership situation that sets the book's scene, dealing with the environmental consequences of land ownership and mismanagement in Britain by both big and smaller landowners, who are morally responsible for its stewardship. Shrubsole describes abundant and varied cases, ranging from long term damage to highland blanket bog cover, to East Anglian Fenland peat depletion, and then the deliberate destruction or logging of Atlantic Oakwood rainforest and the deliberate or accidental introduction of American grey squirrels, feral deer from various corners, and Asian pheasants. Many of the examples he features are familiar to me, my family and friends, from past experience growing up, travelling and hiking there and through many subsequent visits.

Take blanket bog terrains – which are Britain's most extensive and important long-term carbon sinks. They lie in highland moorland areas also favoured by grouse (a plump, ground-dwelling native bird and a magnet to moneyed grouse shooters). Grouse moor landowners – lairds, pseudo-lairds and the otherwise incredibly wealthy – are highlighted by this author as managing their land to protect the grouse to the detriment of most other species, illegally shooting and poisoning threatened raptor species and upsetting plant biodiversity with control burns and drainage trenches. Walking in the High Pennines you encounter many examples of this terrain: take Kinder Scout as an example.

An old friend from uni went to live in Little Hayfield, and the Kinder Scout plateau was virtually in his back yard. Kinder Scout is just over 600 metres above sea level and preserves a thick slab of Kinderscout Grit, a Carboniferous sandstone similar to local sandstones here. There are a number of good local NSW lookalikes in geology, terrain, elevation and annual rainfall, such as Maddens Plains, Barren Grounds, Budderoo and Little Forest Plateau. Kinder Scout is accessible and popular but has been almost loved to death. It falls within the Peak District National Park and is managed by National Trust. But the park authority owns only slightly over 4% of the extensive overall national park area in which Kinder Scout falls and apart from reliable owners and managers like National Trust it has NO legal control over land use in the park area's predominantly private land.

But let's jump to a visit – with friend and my son we climbed onto the Kinder plateau and walked along its west-facing rim. Trying to cross ‘inland’ so to speak however we came up against soil erosion gullies up to more than 2 metres deep. These make up the dendritic pattern you can see in the Google Earth image (which is around 1.5 km across). The gully walls were solid black peat, the vegetation above – thick heather. Looking down on the Kinder Reservoir we could see brown deltas of peat dumped from its erosion.

So what’s going on? Well, lots of bad things: acid rain from the Manchester industrial area, multiple hiker’s boots, historical control burning and grouse shoot management. Kinder Scout plateau it turns out is the most degraded blanket bog area in Britain. So what are the national parks authority doing about it? Well if they didn’t have a benevolent owner like National Trust they would be powerless and toothless! But wait – University of Manchester and environmental organisation volunteers are repairing the damage by replanting of sphagnum and blocking of gullies, but it’s a huge task. Let’s wish them good luck!

So let’s take another example: Blencathra, 868 metres, is the northernmost high peak of the English Lake District lying just north-east of Keswick. My wife Isolde was chasing up some history research for a novel and we ended up at the village of Threlkeld. Talking to locals we heard that the ‘landowner’ of Blencathra had put it on the market and Friends of Blencathra were raising money to buy – would we like to donate?

I think we gave them ten quid, I can’t remember? But this is Lake District National Park isn’t it? You surely can’t buy and sell land here? Well, the answer is, like the Peak District, the park authority owns only 4% of it. National Trust does own a substantial portion, which is great, but a big percentage is still privately owned.

National parks in Australia are all on crown land, ie public land, and managed by national park authorities in their native states. But Dartmoor National Park in Devon is surely also crown land at least in part? 57% of it is actually owned by the Duchy of Cornwall. The right to roam and camp throughout is legally established but a proposal to reintroduce beavers was rejected by King Charles, and who can argue with him? What does William, the current duke say? Who knows?

So let’s round this off by saying this is one of the most thoroughly researched books I’ve ever reviewed and I can recommend it wholeheartedly to anybody who has British connections and environmental love. But it’s also an insider’s look into a complex historical web where many competent and environmentally and legally qualified people are up against a solid wall of history-bound land tenure and vested interests: a country where 1% of the population owns more than half of the land area. Could it evolve to that here? Well in some ways and in part, it probably already has but at least we have free national parks (entry fees or no).

Reviewed by John Martyn
Author: Guy Shrubsole
Publisher: William Collins, 2024
Hardback, 309 pp