Significant Tree Regulations in SA: What You Can and Cannot Remove

South Australia has some of the strongest tree protection laws in Australia, designed to preserve large, mature trees that contribute to the urban canopy, biodiversity, and character of Adelaide’s suburbs. If you have a large tree on your property—or are considering purchasing a property with one—understanding these regulations is essential before you pick up a chainsaw or engage a tree removal service.

For general tree care and pruning guidance that keeps you within the law, professional tree pruning services can advise on what is permitted for your specific trees.

What Is a Significant Tree?

Under South Australia’s Planning, Development and Infrastructure Act 2016, a tree is classified as significant if it meets the following criteria:

Trunk circumference: The tree has a trunk circumference of 2.0 metres or more, measured at a point 1.0 metre above natural ground level
Multiple trunks: If the tree has multiple trunks, the circumference is calculated from the aggregate of all trunks

Additionally, a tree can be classified as significant regardless of size if it is identified in a local council’s development plan as having particular heritage, environmental, or aesthetic significance.

What Is a Regulated Tree?

Below the significant threshold, trees with a trunk circumference of 2.0 metres or more measured at 1.0 metre above ground are regulated. However, the Planning and Design Code has consolidated these provisions and the specific thresholds and exemptions can vary by zone and overlay. Always check the current Planning and Design Code for your specific property.

What You Cannot Do Without Approval

For significant trees, the following activities require development approval from your local council:

Removal: Cutting down, destroying, or killing the tree
Significant pruning: Removing branches that represent more than 30% of the tree’s canopy
Damage to the root zone: Excavation, soil compaction, or construction within the tree’s root zone (typically defined as the area under the canopy drip line plus a margin)
Poisoning: Using chemicals to kill or damage the tree

This applies regardless of whether the tree is on your property. If a significant tree on your neighbour’s property has branches overhanging your land, you cannot prune them beyond the 30% threshold without approval.

When Can You Remove or Prune a Significant Tree?

Development approval for significant tree removal may be granted in the following circumstances:

Dead or dying: The tree is dead, or an arborist report confirms it is in irreversible decline
Dangerous: The tree poses an unacceptable risk to people or property, supported by an arborist assessment
Damaging infrastructure: The tree is causing or will cause significant damage to a building, structure, or essential infrastructure (evidence required)
Pest or disease: The tree has an incurable pest or disease that threatens other significant trees

Even when one of these grounds applies, approval is not guaranteed. The council will weigh the tree’s contribution to amenity, biodiversity, and character against the reasons for removal. For information on related regulatory requirements that may affect your property planning, see our regulations guide.

The Approval Process

If you need to apply for significant tree removal or major pruning:

Engage a qualified arborist: You will need an arborist report (AQF Level 5 minimum) assessing the tree’s health, structure, and risk. Cost: $300–$800
Submit a development application: Through your local council or via the PlanSA portal. Include the arborist report, site plan, and photographs
Public notification: Significant tree applications are generally subject to public notification, meaning neighbours can provide feedback
Assessment: The council assesses the application against the Planning and Design Code criteria
Decision: Approval, refusal, or approval with conditions (such as planting replacement trees)
Processing time: Typically 6–12 weeks for significant tree applications

Penalties for Unauthorised Removal

The penalties for removing or damaging a significant tree without approval are severe:

Fines of up to $120,000 for individuals
Additional requirements to plant replacement trees at the offender’s cost
Potential criminal prosecution for deliberate destruction

Councils actively investigate unauthorised tree removal and have been known to prosecute even when the tree was removed years earlier. Aerial photography and satellite imagery make it difficult to remove a significant tree without detection.

Exemptions from Significant Tree Controls

Some activities are exempt from development approval requirements:

Pruning less than 30% of the canopy in any 12-month period for maintenance purposes
Emergency removal where the tree poses an imminent threat to life or property (though you should document the emergency thoroughly)
Removal of declared pest plant species (check the SA list of declared pest plants)
Certain primary production activities in rural zones

For routine pruning that stays within the 30% canopy limit, our tree pruning guide covers best practices and timing for Adelaide’s common tree species. Understanding these limits is also relevant when planning other landscaping work near significant trees—even changes to the ground level or installation of hardscaping within the root zone may require approval. See our guide on council approval requirements for related development considerations.

Living with Significant Trees

While significant trees can sometimes feel like a burden—restricting what you can do with your property—they also add enormous value. Mature trees provide shade (reducing cooling costs by up to 25%), increase property values (by 5–15% according to various studies), support wildlife, and contribute to Adelaide’s identity as a green, liveable city.

Many Adelaide homeowners find that designing their landscape around significant trees rather than fighting against them produces the most satisfying results.

The Value of Significant Trees to Your Property

While significant tree regulations can feel restrictive, it is worth understanding the substantial value these trees add to your property and neighbourhood. Research consistently shows that mature trees increase residential property values by 5–15%, with large, healthy specimens in prominent positions commanding the highest premiums.

Beyond property value, significant trees provide practical benefits that would cost thousands to replicate through other means. A large eucalyptus with a 10-metre canopy provides shade equivalent to a 75-square-metre shade structure, reducing summer cooling costs by 15–25%. The same tree intercepts approximately 10,000 litres of stormwater annually, reducing runoff and drainage loads on your property.

Significant trees also support biodiversity. A single mature eucalyptus can host hundreds of insect species, provide nesting sites for birds, and produce nectar and pollen that supports pollinators. As Adelaide’s urban canopy faces pressure from development, each significant tree becomes increasingly valuable to the city’s environmental health.

Designing Around Significant Trees

Rather than viewing a significant tree as an obstacle, consider it the centrepiece of your landscape design. Some of Adelaide’s most stunning gardens are designed around mature trees, using them as focal points that provide instant scale, character, and shade that no amount of money can buy quickly.

Key design considerations when landscaping around significant trees include maintaining the tree’s root zone by avoiding excavation, compaction, or changes in soil level within the drip line. This area can be landscaped with lightweight elements: mulch, groundcovers, shade-tolerant plants, and permeable paths that do not disturb the root system.

Elevated decking or boardwalks can bridge over root zones without causing damage, creating usable outdoor living spaces beneath the tree’s canopy. Landscape lighting directed upward through the canopy creates dramatic night-time effects that are among the most visually stunning features in any garden.

If the tree casts heavy shade, embrace it by selecting shade-loving plants that thrive under canopy conditions: ferns, clivias, hellebores, native violets, and bromeliads all perform well in the filtered light beneath Adelaide’s significant trees. The cool, shaded microclimate beneath a large tree is a precious resource in Adelaide’s hot summers—design to enjoy it rather than resent it.

Get Professional Advice

If you have a significant tree on your Adelaide property and need guidance on what you can and cannot do, connect with qualified arborists and landscapers who understand SA’s tree regulations and can help you work within them—or navigate the approval process if removal or major pruning is genuinely necessary.