That single point catches more Hornsby property owners than anything else, because it is the reverse of what most people assume and the reverse of what several tree companies publish.
Is there a size limit for tree removal in Hornsby?
Not in the way it is usually described.
You will find summaries stating that Hornsby requires a permit for trees five metres or taller, or with a trunk diameter of fifteen centimetres or more. That threshold does not appear in the current Hornsby Development Control Plan section on tree and vegetation preservation.
What the DCP does contain is a definition and one height-based exemption. A tree is defined as a long-lived woody perennial plant with one or relatively few main stems, with the potential to grow to a height greater than three metres. Separately, removal of a tree less than three metres in height is exempt, provided it is not located within native vegetation.
So height does appear, but at three metres and as a narrow exemption, not as a five-metre general trigger. You will also see older material describing Hornsby’s controls as applying only to species indigenous to the Shire. That reflects an earlier tree preservation order. The current DCP protects all trees except the listed exempt species, whether indigenous or not.
Which trees are protected in Hornsby Shire?
Under the DCP, prescribed trees protected by the Biodiversity and Conservation SEPP, Clause 5.10 of the Hornsby Local Environmental Plan and this section of the DCP are:
- All trees except the exempt species listed in the DCP’s exempt species table, or those subject to the Biodiversity Offset Scheme
- All trees on land within a heritage conservation area described in the HLEP
- All trees on land comprising heritage items listed in the HLEP
Damaging or removing any protected tree without Council’s written consent is prohibited, except in accordance with the exemptions.
The DCP defines the terms tightly. “Damage” means to impair the value or usefulness, or weaken the health or the normal function of a tree or vegetation. “Remove” means to cut down, knock down, kill, lop or destroy. “Prune” means to selectively remove branches. Note that lopping sits inside the definition of removal.
The exempt species list
Hornsby publishes a table of exempt tree species. It currently includes cootamundra wattle, golden wreath wattle, box elder, tree of heaven, evergreen alder, cocos palm, hackberry, camphor laurel, cotoneaster, loquat, coral tree, rubber tree, honey locust, Norfolk Island hibiscus, privet, poplar, firethorn, golden robinia, willow, umbrella tree, peppercorn tree and rhus.
The table also covers all edible fruit and nut trees, with an important exception: native species such as lilly pilly, blueberry ash and macadamia are not exempt even though they bear edible fruit or nuts.
Camphor laurel appearing on this list is worth knowing, because it is one of the most common large trees in older Hornsby gardens and is frequently assumed to be protected.
Two cautions. Species identification errors are the most common reason an exemption turns out not to apply, and several of these have look-alikes. And Council publishes further information on exempt species on its website, so check the current list rather than working from an article.
What work is exempt in Hornsby Shire?
The DCP sets out these exemptions:
- Dead trees. Removal of a tree deemed by Council in writing, and shown by recorded photographic evidence, to be dead and not required as habitat for native fauna.
- Biosecurity species. Removal of species listed under the NSW Biosecurity Act 2015.
- Light pruning. Pruning of a tree by less than ten per cent of the foliage area, in accordance with AS 4373 Pruning of Amenity Trees, not more than once annually.
- Trees close to an approved building. Removal or pruning of a tree where the base of the trunk at ground level is within three metres of the foundation of an approved building. Detached garages, carports and other buildings ancillary to a dwelling house are excluded.
- Small trees. Removal of a tree less than three metres in height, not located within native vegetation.
- Imminent risk. Trees deemed by Council in writing, and shown by recorded photographic evidence or written evidence provided by a qualified arborist at AQF Level 5, to be an imminent risk to human life or likely to cause substantial damage to property in the near future.
- Council land. Work on Council-owned or managed land, undertaken by Council or Council’s authorised agents.
Two of these deserve emphasis, because they are the ones people get wrong.
The dead tree exemption and the imminent risk exemption both require Council to have deemed it, in writing, before the work. Photographic evidence is part of the requirement, and for the risk exemption Council may accept written evidence from an AQF Level 5 arborist. This is not an exemption you can rely on retrospectively. Take the photographs, get the assessment, and get Council’s position in writing first.
The ten per cent pruning exemption is also narrower than it sounds. Ten per cent of foliage area is not much on an established tree, it must comply with AS 4373, and it can only be used once a year.
When do the exemptions not apply?
The DCP lists the circumstances where none of the above helps:
- All land mapped as Biodiversity on the HLEP Terrestrial Biodiversity Map
- Threatened species, or land containing native vegetation that is habitat for threatened species, populations or ecological communities listed in Schedules 1 and 2 of the Biodiversity Conservation Act 2016, and protected matters under the Commonwealth EPBC Act 1999
- Land within fifty metres of, and including, land containing native vegetation that is habitat or potential habitat for those listed species, populations or communities
- Work contrary to a development consent that requires trees to be retained
- Any work to a tree that is, or forms part of, a heritage item or heritage conservation area
Given that Hornsby Shire contains substantial bushland, the biodiversity and threatened species exclusions apply to a meaningful share of properties. Checking the mapping is part of the assessment, not an afterthought.
What about clearing shrubs and understorey rather than trees?
Hornsby’s DCP treats vegetation separately from trees, and the rules are different again.
Prescribed vegetation protected under the DCP is native vegetation, except where subject to the Biodiversity Offset Scheme, and all vegetation on heritage listed properties under the HLEP. Damaging or removing it without Council’s written consent is prohibited, except under the exemptions.
The main exemption allows clearing of vegetation, excluding trees, on a property once every five years, up to a maximum cumulative area. That area is ten square metres in prescribed urban zones, which covers R2, R3, R4, RU5, SP2, SP3, E1, E2, E3, E4 and MU1, and thirty square metres in prescribed rural zones RU1, RU2 and RU4.
Ten square metres is a small area, once every five years. This is not a general licence to clear an overgrown block.
There are also further exemptions for vegetation deemed by Council in writing, and shown by recorded photographic evidence, to be dead and not required as habitat for native fauna, or to be an imminent risk to human life or likely to cause substantial damage to property in the near future.
The exemptions do not apply to:
- Land with a gradient in excess of twenty per cent
- Land containing marine vegetation
- Land within twenty metres of, and including, a watercourse
- Land within fifty metres of, and including, land identified as Biodiversity on the HLEP Terrestrial Biodiversity Map
- Land within fifty metres of, and including, land containing native vegetation that is habitat or potential habitat for listed threatened species, populations or ecological communities
- Work contrary to a development consent requiring vegetation to be retained
- All vegetation on heritage listed properties, and native vegetation within heritage conservation areas
- Clearing that would fragment or isolate native vegetation
- Clearing that would reduce effective vegetation buffers to adjoining community or private open space
Where the exemption does apply, the DCP sets conditions on how the work is done: it should occur in areas ancillary to an approved existing dwelling or structure, be undertaken by hand rather than heavy machinery, and include replacement planting to stabilise the soil where necessary, using species indigenous to the adjoining vegetation community and excluding anything recognised as invasive.
On a bushland-backed Hornsby block, several of those exclusions are likely to apply at once. Checking the mapping before anything is cleared is the only safe approach.
What is the Biodiversity Offset Scheme, and does it affect me?
The Biodiversity Offset Scheme is established under the Biodiversity Conservation Act 2016 and the Biodiversity Conservation Regulation 2017. Where it applies, it triggers an alternative approval framework for clearing native vegetation rather than the ordinary council permit pathway.
Two things can trigger it: the Sensitive Biodiversity Values Map, and an area threshold based on lot size. The area thresholds set out in the regulation are a proposed clearing area of 0.25 hectares on lots under one hectare, 0.5 hectares on lots under two hectares and on lots of two to thirty-nine hectares, one hectare on lots of forty to 999 hectares, and two hectares on lots of 1,000 hectares or more.
For a standard suburban block, the area threshold is unlikely to be reached. The Sensitive Biodiversity Values Map is the more relevant trigger, and it is checked through the state mapping tool rather than assumed. On larger Hornsby properties, particularly those adjoining bushland, both are worth checking before any planning is done, because the approval pathway changes entirely.
Which application do you lodge?
Hornsby’s DCP sets out the application type by situation.
| Situation | Application |
|---|---|
| Heritage item, work Council is satisfied is minor | Tree Permit |
| Heritage item, major work to any tree | Development Application |
| Heritage conservation area, work Council is satisfied is minor | Tree Permit |
| Heritage conservation area, major work to any tree | Development Application |
| Other land, removal or pruning not subject to the Biodiversity Offset Scheme | Tree Permit |
| Work within the tree protection zone of a protected tree, not subject to BOS | Tree Permit |
| Work contrary to a consent requiring trees to be retained | Section 4.55 application |
Where tree work forms part of other works requiring development consent, it is assessed inside that development application rather than separately.
The tree protection zone rule that catches builders
This is the provision most often missed on Hornsby properties, and it has nothing to do with cutting anything down.
A Tree Permit is required for work within the tree protection zone of a protected tree, including work on adjoining land. The DCP names the work: construction such as driveways, concrete slabs and retaining walls, and earthworks such as changes in soil levels, embankments and trenching.
Hornsby also defines the tree protection zone for this purpose with its own measurements, rather than by calculation:
- Nine metres from a tree with a diameter at breast height of 800mm or greater
- Seven metres from a tree with a diameter at breast height between 400mm and 800mm
- Four metres from a tree with a diameter at breast height of 400mm or less
A new driveway, a slab for a shed or a trench for a stormwater line within those distances of a protected tree needs a permit, even where the tree itself is untouched. On a typical Hornsby block with mature trees, a nine-metre radius covers a great deal of ground.
How are applications assessed?
Council assesses trees using arboricultural, ecological and industry-accepted safety evaluation methods to determine safe useful life expectancy.
The DCP is explicit about what an application for removal must demonstrate. It must show that removal is appropriate, based on an assessment of safe useful life and of risk to human life or property, using an industry-relevant risk assessment method. The DCP names two: Tree Risk Assessment Qualification, known as TRAQ, and Quantified Tree Risk Assessment, known as QTRA.
That is a higher evidentiary bar than many Sydney councils set in writing, and it is the reason a Hornsby application benefits from a proper assessment rather than a form and some photographs.
Where trees are to be retained, AS 4970 Protection of Trees on Development Sites applies. All pruning must be carried out in accordance with AS 4373 Pruning of Amenity Trees.
The DCP also defines who counts as a project or consulting arborist for its purposes: someone who has obtained, through training, AQF Level 5, the Diploma of Arboriculture.
Replacement planting
Any tree approved for removal should be replaced with a tree of like habit, indigenous to Hornsby Shire, planted as near as practicable to the location of the removed tree, grown to maturity, and replaced if the planting fails to survive and thrive, in accordance with Council’s Green Offsets Code.
That is a more specific obligation than a general “plant something” condition. Like habit, indigenous to the Shire, and as close as practicable to the original position are three separate constraints, and the replacement obligation continues if the first planting fails.
Council also runs native plant giveaway days through the year, which is worth knowing when you are costing a replacement.
What if your application is refused?
Section 2.12 of the Biodiversity and Conservation SEPP gives a permit applicant a right of appeal to the Land and Environment Court against a refusal by Council. The appeal must be made within three months of being notified of the decision, or within three months of Council being taken to have refused the application, whichever is later.
In practice, a refusal that turns on insufficient evidence is usually better addressed with a properly prepared arborist report than with an appeal.
What about the tree on the nature strip?
Residents cannot prune or remove a tree on Council-owned or managed land. Nature strips, parks and sportsgrounds are Council’s, and so is the tree work.
If a public tree is a concern, the pathway is a service request to Council, which will have one of its own arborists assess the tree against Council’s assessment principles using a recognised risk assessment method.
Get the tree assessed before you lodge anything
Because Hornsby protects all trees except a named list, the first useful question is not how big the tree is but what species it is and what the mapping says about the land. That is a site visit, not a phone call.
Sydney Tree Company works across Hornsby and the surrounding suburbs, providing tree removal, tree pruning, tree health inspection and evaluation, stump grinding and removal, palm pruning, arborist advice and assistance with council tree preservation paperwork.
Call 0431 732 265 to arrange a free quote and an on-site assessment.