Hardy Irrigation Pty Ltd v Leeton Aerial Ag Pty Ltd - [2025] NSWDC 389

District Court

New South Wales

Medium Neutral Citation: Hardy Irrigation Pty Ltd v Leeton Aerial Ag Pty Ltd [2025] NSWDC 389
Hearing dates: 15 – 19 September 2025 (Albury)
Date of orders: 26 September 2026 (Sydney)
Decision date: 26 September 2025
Jurisdiction: Civil
Before: Newlinds SC DCJ
Decision:
(1) Judgment for the Plaintiff against both Defendants in the sum of $673,518.14, inclusive of interest up to 26 September 2025.
(2) The Defendants are to pay the Plaintiff’s costs of the proceedings.

Catchwords:
AVIATION — Crop dusting — Statutory liability — Damage caused by aircraft while in flight — Strict liability imposed by Damage By Aircraft Act applies to damage caused to crops by crop dusting using incorrect herbicide
BREACH OF CONTRACT — NEGLIGENCE — Crop dusting — Allegation that Defendants sprayed Plaintiff’s cotton with herbicide contaminated with 2,4-D, which is toxic to young cotton, causing the Plaintiff loss and damage — Finding of breach of contract and liability under the Damage by Aircraft Act based on inferences — No breach of duty of care established
DAMAGES — Proper measure of damages to be awarded for economic loss occasioned by damage to particular cotton fields

Legislation Cited:
Damage by Aircraft Act 1999 (Cth) s 10; s 11

Cases Cited:
Blatch v Archer (1774) 1 Cowp 63
Bootle v Barclay [2013] NSWCA 142
Bradshaw v McEwans Pty Ltd (1951) 217 ALR 1
Briginshaw v Briginshaw (1938) 60 CLR 336
GIO (NSW) v Fredrichberg (1968) 118 CLR 403
Mummery v Irvings Pty Limited (1956) 96 CLR 99
N M Rural Enterprises Pty Ltd v Rimanui Farms Ltd [2013] NSWSC 309
Scott v London St Katherine Docks Co (1865) 159 ER 685

Category: Principal judgment
Parties: Hardy Irrigation Pty Ltd (Plaintiff)
Leeton Aerial Ag Pty Ltd (First Defendant)
JN Aviation Pty Ltd (Second Defendant)
Representation:
Counsel:
S Burt (Plaintiff)
J D Catlin / S Hinchliffe (Solicitor) (First and Second Defendants)
Solicitors:
Litton Legal (Plaintiff)
Princeton Legal (First and Second Defendants)

File Number(s): 2024/163058
Publication restriction: Nil

JUDGMENT

Introduction

The parties

The Plaintiff is a company owned and operated by the Hardy family. It operates a very large farming operation between Coleambally and Jerilderie in the Murrumbidgee region of New South Wales. It grows cotton as its main summer crop and a variety of other crops in the winter season. The overall farm is made up of various parcels which are not contiguous and are located in three separate areas. Those three areas are within about 15 kilometres of the other. Within each area are lots or paddocks identified by individual numbers which refer to areas known as “Farms” and areas within the Farms that are known as “fields.” For example, the area described as 520(2a) is Farm 520, field 2a.
Below is a map showing the three overall farming operations in white lines and indicating the number of each Farm and field.

Farming cotton and the other crops requires the use of large amounts of herbicides to, amongst other things, keep weeds which grow amongst the cotton down.
The Plaintiff carries out a lot of spraying of its crops itself by using a machine known as a Miller N2XP, which distributes chemicals by the use of long boom arms. The Plaintiff buys and stores herbicides of various types on its property. Those herbicides include 2,4-D, Weedmaster, various types of related products known as “Roundup,” and many others. The Plaintiff’s agronomist, Brett Hay of Nutrien Agriculture Pty Ltd, advises the Plaintiff of what he considers is necessary as far as spraying is concerned, and the Plaintiff generally accepts and implements that advice.
From time to time, the Plaintiff, when advised by Mr Hay that aerial spraying is required, retains the first Defendant to carry out crop-dusting on particular areas of its property, which services are provided by the second Defendant.
The first and second Defendants operate a crop-dusting business. The first Defendant enters into contracts to do crop-dusting. The second Defendant, which is a related company to the first, owns and operates the aircraft used to do the spraying. Jason Neutze controls those companies as he is the sole Director of both. He and his wife, Jacqueline, own all the shares in both companies. The two companies collectively carry on the business under the name “Mas AG.”

The Plaintiff’s case

In November 2022, the Plaintiff retained the first Defendant to carry out crop-dusting on a number of specific fields within its property, then growing young cotton. The cotton was to be sprayed with “Weedmaster.” Its active ingredient is glyphosate. Weedmaster is a tradename for a particular chemical compound marketed by a particular supplier. A very similar, but not identical compound is also distributed under the trade name “Roundup.”
There is another chemical compound known as “2,4-D” which is used to spray some weeds and crops in certain circumstances but is highly toxic and destructive to cotton, especially young cotton. 2,4-D is not in either Weedmaster, or the standard types of Roundup.
As one of the many experts in this case, Mr Somervaille, explained:

“Cotton is extremely sensitive to 2,4-D with doses as low as 0.53 g active/ha having a disruptive effect on cotton growth. Effects and sensitivity will vary with cotton growth stage and growing conditions at the time of and following exposure.
2,4-D as a synthetic auxin affects cell division to produce abnormal growth. Symptoms including leaf distortion, production of unusual venation and abortion of reproductive tissue preventing setting of viable fruit.
…
Delays in development may not lead to losses in production in growing regions where compensatory growth may occur. However, in short-season areas such as Coleambally, developmental delays may have a much more serious impact compared to growing areas which have a longer growing season e.g. northern NSW, Qld.”

Whilst the many experts in this case do not agree about much, there is general agreement as to the above observations.
The Plaintiff's contends that, shortly after the crop-dusting was carried out, the cotton in the fields sprayed became severely damaged because, on the Plaintiff's case, at the time its fields were sprayed by the Defendants, mixed in with the Weedmaster, was 2,4-D, which is the direct cause of that damage. The symptoms exhibited on the affected crop were, on the Plaintiff’s case, consistent only with 2,4-D poisoning.
The Plaintiff claims economic loss, being the difference between what it assesses would have been the outcome of the affected cotton if not for the damage caused by the spraying and the actual outcome.
The herbicides sprayed by the Defendants were obtained direct from a supplier, Nufarm Australia Limited, and delivered directly to the Defendants’ hangar, in what is known as an Intermediate Bulk Container (“IBC”) but usually referred to as a “shuttle.” A shuttle is a 1000 litre plastic container with a lid on the top and a tap towards the bottom, via which the liquid inside can be extracted. The way this occurs in the Defendants’ hangar is that it is first put in a “hopper” or mixing trough. In this case, it was mixed with some water and then pumped into the plane. The Defendants’ hangar and chemical storage shed is filmed by CCTV cameras. I have viewed footage of the substance in the shuttles being mixed in a hopper and then the planes being filled with the herbicides for some, but not all, of the relevant trips conducted by the Defendants, the subject of the case. The balance of that footage covering all of the trips was not retained by the Defendants.
It is neither the Plaintiff’s, nor the Defendants’ case that the shuttle arrived at the Defendants’ premises from Nufarm already contaminated. I am satisfied that, at the time that the chemicals in the shuttle were delivered to the Defendants’ premises, they did not include any 2,4-D. They were Weedmaster and were not toxic to young cotton.
The spraying, which was carried out by the second Defendant, took place on the Plaintiff’s property at the various specific requested farms and fields between about 5 and 16 November 2022. Shortly thereafter, various people noticed damage to young cotton in all of those fields.
On the Plaintiff's case, by late December 2022 when chemical analysis was carried out on the residue of chemicals in the shuttle, there was a quantity of 2,4-D that had been somehow mixed in with Weedmaster. The result of that chemical analysis is consistent with observations made by the various members of the Hardy family and Mr Hay in December that the liquid inside the shuttle was a distinct yellow colour when, ordinarily, glyphosate is a blueish colour. There is agreed expert evidence to the effect that a yellow colour is indicative of 2,4-D. The result is also consistent with the observation that the relevant cotton was displaying symptoms consistent with 2,4-D poisoning.
The Plaintiff’s case boils down to the following:

Upon delivery of the shuttle to the Defendants, there was no 2,4-D in it;

Shortly after the spraying took place there was observable damage to the crops consistent with 2,4-D having been sprayed on the crops. That damage was uniform and specific to the area that had been sprayed by the Defendants; and

On 13 December 2022 when the shuttle was collected by the Plaintiff, there was 2,4-D in the residue in the shuttle in which the chemicals had been delivered. This is confirmed by CCTV footage. Thomas and Perry Hardy and Mr Hay observed the residue was yellow (which indicates the presence of 2,4-D), and a subsequent chemical analysis of a sample of the residue in the shuttle arranged by Mr Hay identified the Weedmaster as contaminated with 2,4-D.

From those primary facts, the Plaintiff seeks a finding by inference that, when the crops were sprayed by the Defendants, the chemicals had become contaminated with 2,4-D, which has caused it loss and damage.
How that 2,4-D got into the planes is something the Plaintiff does not seek to prove. Nonetheless, the Plaintiff contends that the most likely explanation is that, somehow by mistake whilst under the control of the Defendants, it got into the shuttle at the Defendants’ premises.

The Defendants’ answer

The Defendants deny any liability and contend that the Plaintiff has failed to prove that any damage that may have been suffered to the crops was caused by 2,4-D being sprayed on those crops by the Defendants.
The Defendants contend that, for such a conclusion, there is required a reasoning process that involves an impermissible amount of speculation and guesswork, or that even if it is a possibility, it is but one of a number of competing explanations and that the Court ought not make a choice between what it contends are conflicting inferences of equal degrees of possibilities so that the choice between them is a mere matter of conjecture: see for example the observations in Bradshaw v McEwans Pty Ltd (1951) 217 ALR 1 at 5.
The Defendants also contend that fundamentally the Plaintiff's case has embedded in it allegations, which can only described as either gross negligence or something worse. Upon that analysis, the Defendants rely on cases such as Briginshaw v Briginshaw (1938) 60 CLR 336 (“Briginshaw”) and say that “"reasonable satisfaction" should not be produced by inexact proofs, indefinite testimony, or indirect inferences.”
The Defendants have called uncontested evidence as to their process and procedures for handling chemicals and to the fact that their records show no 2,4-D was in their possession in November 2022. The Defendants point to “spray drift” and/or subsequent spraying of the same areas by the Plaintiff as competing explanations as to what happened, which they say are at least equally open, if not more likely.

The various legal bases of the Plaintiff’s claim

The Plaintiff's legal case against the first Defendant is, firstly, based on contract. The proposition being the contract to spray the fields required a particular chemical herbicide to be sprayed, viz. Weedmaster, and that any departure from that particular herbicide is a breach of contract. If the underlying facts are proved, i.e. that, mixed in with the Weedmaster, was 2,4-D, I consider that breach of contract against the first Defendant would be made out. The contract required Weedmaster, not Weedmaster contaminated with 2,4-D.
The Plaintiff also claims damages against both the first and second Defendants for breach of duty of care, alleging that there was a duty imposed on both Defendants to the effect that reasonable care would be taken to not spray the Plaintiff’s cotton with toxic chemicals. It seems to me self-evident that such a duty exists. However, there is a question as to proof of breach in circumstances where the Plaintiff cannot demonstrate what went wrong in the Defendants’ operation. The Plaintiff relies on the reasoning sometimes referred to as “res ipsa loquitur” and says that, if the underlying facts are proved, the outcome bespeaks only a breach of duty.
The Plaintiff also relies on the provisions of the Damage by Aircraft Act 1999 (Cth) (“Damage by Aircraft Act”), which impose a strict liability on both the owner or operators of aircraft in relation to any damage caused by any “thing that dropped or fell from an aircraft in flight” (s 10(1)(c) of the Act) and relies on what the Court of Appeal said in Bootle v Barclay [2013] NSWCA 142 (“Bootle”) to the effect that, properly construed, the Act applies to chemicals deliberately sprayed from an aircraft onto someone’s property.
If the underlying facts contended for by the Plaintiff are proved and assuming the Damage by Aircraft Act applies to crop-dusting (which is disputed), strict liability for economic loss consequent on damage caused to the Plaintiff’s cotton would attach to both Defendants, regardless of any fault on their part.

Liability

I will return to the various legal ways the Plaintiff puts its case, but first I will decide the factual issues. Ultimately, the factual case on liability boils down to the question of whether the Defendants sprayed 2,4-D on the Plaintiff's property.

Consideration

What happened?

The Plaintiff's case is attractively simple, although that apparent simplicity masks some complexity. The Plaintiff calls direct evidence to the effect that significant damage consistent with 2,4-D poisoning was observed in cotton in paddocks that had been the subject of aerial spraying by the Defendants.
The symptoms of 2,4-D poisoning on cotton are very distinctive. The leaves become shrivelled up, brittle, and display a distinctive style of what is known as “witches hands." I am satisfied that those symptoms were observable on the cotton that was sprayed by the Defendants. Those symptoms were uniform in the way I will describe. For reasons I will explain, I come to this conclusion notwithstanding some contemporaneous observations and opinions to the contrary by Mr Hay.

Observations as to symptoms/changing opinions as to cause/uniformity of damage

The evidence of Mr Perry Hardy and his two sons, Thomas and Stephen, is to the effect that they observed just those symptoms in the cotton in the affected paddocks. There are a number of photographs taken at the time which confirm their observations. I consider them to be honest and reliable witnesses.
Mr Brett Hay, the Plaintiff’s agronomist who had recommended the spraying, made observations in the weeks following the spraying to the effect that some of the paddocks were affected and some not affected and that the observable damage may, in his opinion, have been caused by “spray drift” from adjoining fields and/or “sandblasting” and/or the pest known as “thrip.” However, by mid-December he had become convinced that the problem was 2,4-D poisoning and that the 2,4-D had been sprayed on the cotton by the Defendants.
It is submitted by Mr Catlin on behalf of the Defendants that what he describes as inconsistency between the Plaintiff’s various witnesses on this topic is significant. He also emphasises that all of those witnesses originally thought spray drift was responsible and then changed their minds. I do not consider such inconsistencies that there may be have the significance attributed to them by Mr Catlin. The observations made by Mr Hay were not necessarily made at the same time as those made by various members of the Hardy family. Mr Hay was not conducting his observations for a forensic purpose to be used in a court case. His observations may well have not been as careful or complete as they might otherwise have been. Moreover, the time it takes for the damage to become apparent is not necessarily uniform. Mr Catlin also emphasis what he characterises as a sudden change of opinion by the Hardys and Mr Hay. Mr Hay and the Hardys for a time all believed the damage was caused by poisoning from spray drift from adjoining properties. Over time as more information became available, they came to believe it was from the Defendants’ spray. I do not find that sort of change of opinion, in the context of emerging facts, to be as unusual or sinister as the Defendants would have it.
Mr Hay was cross-examined as to what was described as his “sudden change of opinion". He had, in his Affidavit, already explained how and why his opinion changed and I found his explanation to be, not just plausible, but understandable. I certainly found it to be honest. Despite it being floated in final submissions that perhaps he was not being honest, he was never confronted with such a proposition in cross examination, nor was that submission made, rather the submission was that he ought be found to be an unreliable witness.
What happened from Mr Hay’s perspective is that, shortly after the spraying, he noticed damage to the crops which he identified as herbicide damage. He initially considered this to be the product of what is known as “spray drift” from spray operations which may have taken place on adjoining properties with toxic spray having drifted onto the Plaintiff’s crops. Spray drift is a common problem in this and other regions. He thought it the most likely explanation, which I consider was reasonable. Additionally, he initially did not notice that the damage coincided with the areas that had been sprayed by the Defendants and indeed considered some of the damage not to be the product of herbicide poisoning at all, but rather the product of sandblasting and/or possible thrip infestation.
In relation to Farm 502 (3) and Farm 524 (2), being the areas which he attributed to sandblasting at the time, he said at paragraph [11] of his Affidavit, “I attributed to sandblast and thrip damage but in hindsight was likely herbicide damage.”
In relation to Farms 502 (3) and Farm 524 (2,3 and 5), he said that, on 1 December 2022:

“I came in at the top of Farm 502 (3) and was shocked by the damage that, at that time, I assumed was spray drift and noted in my observation that damage appeared to have come diagonal across the paddock. It looked as though the damage was more concentrated from one side of the paddock to the other which could have been from the neighbouring paddock

As to Farm 520, he said:

[In relation to] Farm 520 fields (2a), 2(b), (2c), (2d), (3a), (3b) and (3c). I didn't notice any damage to these farms at this time.”

He explained his change of opinion as follows:

“As of 1 December 2022, I was still of the view that the damage I was seeing could have been spray drift. It wasn't until 12 December 2022 that it became apparent that all the paddocks that had been sprayed with Weedmaster subject to my recommendations had herbicide damage.”

Finally, he said:

“Following my observations on 12 December 2022 and into on or around 13 December 2022, I continued to piece together what was happening and realised that it was evident that something was wrong with what had been sprayed on the paddocks by Mas AG.

…
all the cotton that was showing damage was subject to those recommendations [for aerial spraying by the Defendants] except for the strip at 208 (2) which was resprayed.”

I accept all of the above evidence and, in general, found Mr Hay to be a reliable and honest witness.
Until about the middle of December, various members of the Hardy family, in particular Perry and Stephen, were firmly of the view that spray drift was the problem as they sent out group texts to neighbours and made Facebook posts to that effect, warning people of the risks associated with spray drift.
They were also cross-examined on what was said to be a sudden change of heart, but again, I think their change of opinion is explicable by more and more information becoming available to them. Moreover, at the time, they were in large part relying on Mr Hay’s opinion, which, as I have explained, evolved over time.
Again, I reject any suggestion that any of the Hardys or Mr Hay deliberately lied and/or manipulated evidence so as to sheet home liability for the damage they felt they had suffered to the Defendants because it was not possible to identify who they knew to be the real culprit, that is an anonymous neighbour guilty of spray drift. Such a suggestion, which is contained in Mr Bell’s expert Report, was never put to the Hardys or Mr Hay, who I consider were all honest witnesses. In any event, the submission was not made, rather they were said to be unreliable witnesses. I reject that submission. Their memory is not perfect, but I would not expect it to be. However, I am satisfied that, in general terms, they were both honest and reliable witnesses.
As to the observed damage, there is not only the observations of the Hardys and Mr Hay, there is also direct evidence from Mr McGuinness, a highly credentialled expert. Mr McGuinness gave evidence that the damage he saw some time later in March or May 2023 before the cotton was harvested was consistent with 2,4-D damage occurring in or around a very early stage of their development. He gave direct evidence that he actually inspected the crops and was confident that what he was seeing was the result of 2,4-D poisoning at an early stage of the cotton's development.
Mr McGuinness considered the damage he observed to be uniform across the areas sprayed by the Defendants. The exception to this was what was described as a “shadow” area around a haystack in Farm 520 which he considered was consistent with the aeroplane having avoided the haystack and a particular strip in field 208(2), where there was a “strip” of damage to cotton in the middle of an otherwise undamaged field. Mr Somervaille, another expert, considered this observation about the haystack and strip to be significant and only consistent with aerial spraying.
The observations by Mr McGuiness about the haystack “shadow” and the strip were consistent with observations made by the Hardys and Mr Hay in November and December 2022.
As far as the strip is concerned, it is in a field that was not sprayed by the Defendants pursuant to the relevant contract, but had been sprayed earlier successfully by them, other than a strip which had been noticed by Mr Hay as having been missed on the earlier occasion. As part of the contract the subject of this claim, the Defendants were requested to spray just that strip. This they did and thereafter it was only that strip that exhibited the damage observed by, not just the Hardys and Mr Hay, but also by Mr McGuinness. Indeed, it can be seen specifically in some photographs.
The consistent evidence of Mr Hay, the Hardys, and Mr McGuinness is that the damage was coextensive with the precise areas sprayed by the Defendants, including the particular strip in field 208(2) and the shadow around the haystack on Farm 520. The Defendants take issue with this evidence, based on the contemporaneous observations of Mr Hay where he did not notice such consistency until sometime around the middle of December 2022. Mr Catlin’s point is that the agreed science is that symptoms would have been apparent at the latest about two weeks after spraying and therefore, by at least early December, Mr Hay should have not just noticed damage, but he should have noticed uniform damage in all of the fields sprayed by the Defendants, which, in the reports he made at the time, he did not.
It needs to be remembered that Mr Hay was assuming at the time that spray drift was the cause and he was not thinking in terms of the crop-dusting carried out by the Defendants having anything to do with what he was seeing. I do not consider the fact he did not notice damage in some fields on certain inspections is conclusive of there being no damage. It proves that he did not notice it at the time and is therefore relevant but is not determinative. As I have already recorded, he explains this by saying he did not notice the damage at the time.
There is another more nuanced aspect of this notion of uniformity as explained by Mr McGuinness. The way 2,4-D damages plants upon which it is sprayed is not to cause damage to the growth that already exists but rather it causes cellular damage by damaging the DNA of the plant, which means that any future growth from that point on will exhibit the symptoms. Mr McGuinness’ clear and uncontradicted evidence was that the damage he observed in 2023 was uniform, not just across the areas sprayed by the Defendants but was also uniform in the sense that the damage had been caused at around the same time, because the damage can be seen to start from similar points in the growth of cotton from field to field.
The Defendants’ answer to this observation is that it should not be given any weight because, again, it is not consistent with Mr Hay’s contemporaneous observations. That submission rather misses the point. Mr McGuinness' explanation as to the way the damage works on the cotton is consistent with the damage having occurred at the same time which is inconsistent with spray drift or subsequent spraying by the Plaintiff as potential explanations but is consistent with the damage being caused by the Defendants’ spraying. It is also consistent with there having been damage at the time and Mr Hay not noticing it.
For those reasons, I am satisfied that the damage to the cotton was uniform and consistent with aerial spraying by the Defendants in November 2022.

The colour of the residue

A substantial event in the minds of the Hardys and Mr Hay was observations they say they made as to the colour of the residual chemicals in the shuttle on 13 December 2022, when Perry Hardy and Stephen Hardy collected it from the Defendants’ premises.
They say, at the time, that they noticed it was a distinctive yellow colour which was not consistent with the normal dark bluish colour of Weedmaster as they understood it to be. It is common ground that, ordinarily, Weedmaster will be a dark blueish colour, but if mixed with 2,4-D will turn a yellow colour.
They both gave evidence that Stephen had a discussion with Jason Neutz, where the colour was raised as something that was considered to be unusual.
Mr Neutz denies any such conversation took place, which evidence is corroborated by the evidence of Dana Honour, an employee of the Defendants, who was present on 13 December 2022 and, on 24 May 2023, prepared a statement as to her recollection, which conformed with evidence she gave before me. She was also cross-examined. Her evidence is that there was a discussion between Mr Perry Hardy and Jason Neutz, where Perry Hardy expressed concern that there had been toxic damage to his cotton, which at the time he was attributing to the use of an herbicide, being Agixa (a rice herbicide), and that it had affected 300 ha of his cotton.
She does not remember there being any disagreement between the Hardys and Mr Neutz or any colour discrepancies of the chemicals being discussed.
Mr Neutz emphatically denies any significant discussion at the time about damage to cotton and denies any suggestion that there was a discussion that the residue chemicals looked yellow at the time. His evidence was that they looked the normal colour, that is a bluish colour.
When the shuttle was returned to the property of the Plaintiff's, the evidence of Stephen Hardy is that he became more and more concerned as to the colour of the residue and, on 16 December 2022, took two photos on his mobile phone, which he sent by text to Mr Neutz.
I set out below those photographs, which do tend to suggest a yellow colour in the residue in the shuttle.

There then followed some email correspondence where Mr Neutz emphatically denied any issue with the spraying conducted by his companies and emphasised that, regardless of what the photograph sent on 16 December depicted, as far as he was concerned, the liquid was not that colour when it left his property. He suggested that it had been in some way interfered with after that time so as to cause the change in colour and was very suspicious that the Plaintiff was seeking to manipulate the photographs to hold his companies liable for conduct that he did not feel they were responsible for.
As I have said, there is CCTV footage of the collection of the shuttle on 13 December 2022.
Whilst it does not show any discussion between either of the Hardys and Mr Neutz, ultimately Mr Neutz accepted that there was a discussion. The question becomes, what was said?
It is possible to see the residue liquid in the shuttle as it is collected in the footage. To my eye, the residual chemical contents in the shuttle in the footage has a bluish colour and is consistent with other shuttles containing presumably the same chemicals nearby. It does not look yellow to me.
There was, however, expert evidence called by both parties as to the ability of people to assess colours by reference to CCTV footage of the type taken of the events on 13 December and, for that matter, in the various other videos I have before me of the loading of the plane with the chemicals in November, all of which, as I have said, to my observation do suggest that the liquid inside the shuttle was a bluish colour.
The evidence of Mr Khoury, expert for the Plaintiff and Mr Le Roux, expert for the Defendants, who had both analysed the digital footage from the CCTV cameras, was that it would not be safe to make an assessment of the colour of the liquid by reference to the video footage. This is because the way digital images are stored and transported is that they are digitalised into pixels and then significantly compressed which has an impact on, amongst other things, the veracity of the colours depicted. This is especially so in CCTV footage taken in poor light.
Having heard them give evidence concurrently, I am satisfied that, whilst my own uneducated observations of the CCTV footage on 13 December would lead me to conclude that the residual liquid was probably blue, the expert evidence is such that I consider that I ought not make a finding as to colour based on the footage at all. Rather, I should proceed upon the basis that the video evidence is inconclusive and that the residual liquid may well be yellow or blue or for that matter some other colour. I will take the same approach to the apparent yellow that I can see in the photographs sent on 16 December. They are also digital, having been taken on a mobile phone camera.
That then leaves a conflict in the evidence given by Stephen and Perry Hardy and Mr Hay on the one hand, and Mr Neutz and Ms Honour on the other.
I found them all to be credible witnesses. None of them evinced any of the characteristics of a witness lacking in credibility. I felt they were all careful not to overstate their positions, even though the Hardys and Mr Neutz obviously have significant interest in the outcome of these proceedings.
I accept that each of the Plaintiff’s witnesses have an honest recollection and belief that they saw the liquid was yellow at the time they collected it and that Mr Neutz and Ms Honour have the equally honest belief that it was blue.
As to whether there was a specific discussion about the colour of the liquid on 13 December 2022, I think it is more likely than not that there was. However, it was not in the context of an accusatory statement. Rather, it was more along the lines of a question, which may well not have been understood as significant, and I think it plausible that Mr Neutze and Ms Honour do not remember it.
Objectively, I am satisfied that, come 16 December 2022, the Hardys believed that the liquid was yellow, which is why Stephen sent the photographs to Mr Neutz by text message.
Perry Hardy also rang Mr Neutz around then, and they had a conversation where, effectively, the allegation was made, to which Mr Neutz took issue, which provoked some aggressive emails. Nonetheless, objectively, I am satisfied that the Hardys did believe the liquid was yellow as at 16 December 2022.
Mr Hay also saw the liquid after it had been collected and thought that it was yellow, which he considered was inconsistent with Weedmaster. When he thought about it in the context of the observations he had made as to damage, he considered this was significant, which provoked him to organise for a sample of the residue to be sent to a lab to be tested to see if it was contaminated.
The fact that the Hardys sent the photographs by text and Mr Hay took steps to get a sample tested is reliable, objective, and contemporaneous material which supports their evidence as to the colour they observed at the time.
I am satisfied that it is likely that the residual chemicals in the shuttle at the time it was collected by the Defendants on 13 December appeared yellow, which is indicative of it being having been contaminated with 2,4-D by the time of those observations. On its own, I would not be prepared to act on that finding so as to conclude that 2,4-D was present, but I consider the likelihood to be sufficient so as to take it into account as part of the overall package of available evidence.

The chemical testing/chain of custody

That then leads to the chemical analysis carried out by ACS Laboratories. There is a report, dated 22 December 2022, which confirms that what had been tested contained Weedmaster contaminated with 2,4-D.
The certificate of analysis describes as "product name," “Hardy Irrigation Roundup sample."
Of course, the proper description, if the sample came from Hardy Irrigation, was “Weedmaster sample.” However, as I have said, the two tradenames are sometimes, but erroneously, used interchangeably.
There is a real question here as to the chain of custody of the sample.
The evidence is as follows:

Mr Hay was going to collect a sample from the Plaintiff's farm himself.

He became busy on the day and rang a staff member, Lachlan Vogan. Mr Vogan went to the Plaintiff’s farm, which was unattended, and identified a shuttle with residual chemicals in it, amongst two possible shuttles. He satisfied himself that it was the correct shuttle by reference to the label, which had on it a sticker that it was to be delivered directly to the Defendants’ hangar (this is consistent with what is on the shuttle in the various videos), then took a sample from the residue by getting an empty “Powerade" bottle out of his car and using the tap on the shuttle to get some chemicals into the Powerade bottle.

Mr Vogan then returned to the office of Mr Hay, which was unattended and left the sample somewhere in the office.

Mr Hay then gave evidence that he “sent” the sample to the lab, although there is no detail or information as to how he identified the sample, how it was sent, or what paperwork, if any, went with it.

Finally, there is the certificate of analysis and the evidence of Mr Famulari of ACS Laboratories, to the effect that the usual practice of the laboratory would be to record the product name by reference to either what was written on the container containing the sample or, alternatively, on some paperwork that went with it.

There is clearly a series of large gaps between the taking of the sample, putting it into the Powerade bottle, delivering it to an empty office, it being sent of testing, and the testing, the subject of the Report. The question is, on the evidence available, is it more likely than not that the chemicals that were tested and are the subject of the Certificate were chemicals from the residue in the shuttle that had originally been delivered to the Defendants’ hangar.
Taking it step-by-step, I am satisfied on the balance of probabilities that Mr Vogan took the sample from the correct shuttle. It follows that, unless the residue in the shuttle had been deliberately interfered with in some way, which I consider very unlikely, what was sampled was the residue that was in the shuttle when it was collected from the Defendants’ premises on 13 December 2022.
I also accept that Mr Vogan delivered the Powerade bottle with the sample in it back to Mr Hay’s office, and that shortly thereafter Mr Hay sent what he believed to be the sample taken by Mr Vogan to the lab for testing. There is clearly room for him to have made a mistake here. By inference, he must have sent some paperwork, even if it was an email identifying that it was on its way and the testing that was required. The statement on the Certificate itself is a business record, probably made by someone with knowledge of the fact, the fact being that, either on the sample or with paperwork that arrived with the sample, there was a statement to the effect that this was “Hardy Irrigation Roundup." To describe Weedmaster as Roundup and vice versa is understandable but is an unlikely mistake for someone like Mr Hay to make.
When I take those various facts and put them together, whilst obviously enough I have doubt, I consider that there is a real possibility, short of a probability, that what was tested was the residue from the shuttle. I would not be prepared to act on that finding if it was the only fact relied on by the Plaintiff. However, like my finding as to the colour of that residue, I think the likelihood is such that it is appropriate to take it into account along with the other evidence.

The significance of the symptoms and the possibility of spray drift: the expert evidence

Returning to the evidence as to the damage. There was expert evidence called by the Plaintiff from Mr Somervaille and Mr McGuiness. The Defendants called competing expert evidence from Mr Bell.
All of them prepared reports and they gave evidence before me concurrently in a way that I found extremely professional, productive, and helpful, which is a credit to all of them.
The Reports of Mr Somervaille and Mr McGuinness were also written and presented in a very considered, professional, and what I thought was an objective manner appropriate for independent experts seeking to assist the Court as opposed to advocating a case theory. I reject the submissions made by Mr Catlin on behalf of the Defendants to the effect that, because they were retained by the Plaintiff to prove a case against the Defendants, that they had become “bloodhounds" looking only for evidence in support of the Plaintiff's case theory.
That submission was made in circumstances where this criticism had not been put to either Mr Somervaille or Mr McGuinness in cross examination. I do not consider it to be a fair submission, and it is inconsistent with how they both presented as witnesses both in writing and in the witness box.
Unfortunately, the same observations of objectivity and balance cannot be said for Mr Bell's written evidence. A reading of Mr Bell's various Reports leads me to a conclusion that he considers himself to have expertise in fields way beyond his actual field of expertise, but more critically, was conducting himself very much as an advocate for the Defendants’ cause. The Report needs to be read in full to understand why I have taken that view, the following examples from his Report are I think instructive:

“7.14 It is my professional opinion that Hay clearly changes his mind once he is informed of the potential for herbicide contamination to have occurred. He now makes reference as per section 31 of his Affidavit that the damage was consistent with herbicide application and from my experience, phenoxy application would have caused that damage.
…
7.26 As shown in Figure 1 below, I would expect a diligent expert [referring to Mr McGuiness] to have walked each paddock in a diagonal cross section across each paddock to assess the potential damage to the cotton.
…
7.34 I would expect that diligent professional agricultural consultant [referring to Mr McGuiness] would make all enquiries necessary and gather all of the facts before providing an opinion.
…
8.2 It is my opinion that it is highly possible that the Plaintiff deliberately added 2,4-D to the remaining glyphosate in a given shuttle.
8.3 I have reached this conclusion for the following reasons:
a. In order for a Plaintiff to seek financial compensation as a result of herbicide damage to a given crop either from direct spray application or from spray drift the Plaintiff must have a “culprit”, a Defendant.
b. With spray drift it is often very difficult to determine where the drift has actually come from, thus there is no “culprit” and no potential financial compensation.
c. If the herbicide came from direct aerial application, then the damage would be relatively even up and down a given spray swath and across a paddock. This was not the case as Hay often referred to herbicide drift being from phenoxy or Agixa. Hay also refers to multiple drift events.
d. I would expect a good prudent agronomist to investigate as to the possible source of this drift or drift events. Hay did not do this.
e. The Hardy cotton paddocks are surrounded by mixed farming paddocks which in November/December 2022 could have been rice, maize, winter cereals, grain legumes, canola, fallow paddocks and pasture. Any one of these farms could have been spraying with a Group 4 herbicide. Ie. As per Hay’s email on the 12th of December “Agixa looks the culprit on 208 and 502”. Agixa is a rice herbicide.
f. I would expect a good prudent agronomist to take plant samples and have these analysed to potentially determine the herbicides present. This was not done.
…
h. The ACS Certificate of Analysis (23/1/23) on page 4 refers to Hardy Irrigation Roundup sample. This sample does not appear to be Weedmaster.
i. There is no chain of custody for the sample, no IBC batch number and if the sample was taken there is no reference to good Standard Operating Practice.
j. In the video taken on the 9/12/22 the grower states “so this is what our cotton looks like and this is what it looks like at the other end of the paddock where it did not get drift on it. If people could stop drifting there spray onto out cotton that would be fantastic”. So one end of the paddock had no damage yet it was sprayed by air. The only conclusion from this video is that the grower is correct the damage has been caused by spray drift.
…
l. A text (page 36 of Binder 1) shows a text message from Perry stating, “we now have 300 ha cotton across 5 farms effected by overspray probably Phenoxy or Agixa”. The area of 300 ha is considerably larger than the area that MAS Agwork sprayed. Thus the damage could not have come from MAS aerial application. The text also refers to phenoxy or Agixa. There are many Group 4 herbicides. I would have expected the Plaintiff to fully investigate the source of the overspray.
m. Extensive personal experience regarding spray drift shows that spray drift occurs ad-hoc in a given crop and is very variable across a given crop. Spray drift would rarely occur throughout the entirety of a crop. This is highlighted in Hay’s cotton inspection on the 12th December 2022 for field 208/2 where it is stated “crop has phenoxy damage from Nth, channel bank has stopped it going into Pdk 4”.
n. No independent agronomist or consultant inspected the herbicide once observed in early December 2022 until McGuiness inspected the crops on May 1, 2023. I would have expected that the Plaintiff would have engaged an independent expert to assess the herbicide damage throughout the season.
o. If 2,4-D is applied or drifts onto cotton I would expect that damage would be observable within 3 to 5 days. Hay refers to herbicide damage in his report on the 1/12/2022 to fields 502-3 “as damage appears to have come from diagonal across paddocks”. This is 27 days after the field was aerially sprayed. It is my opinion that this observed damage was from spray drift and not from direct spray application.
p. Based on page 37 of Binder 1 the remaining glyphosate in the shuttle was blue as per video and observations of two staff members. Based on the simple trial undertaken by Somervaille the addition of 2,4-D to Weedmaster has turned the Weedmaster yellow in colour in 12 days during September. It is my opinion that this chemical reaction would be temperature dependant and would occur considerably faster in December when temperatures are hot. Even the 50 Lts left in the shuttle would be warm on a hot day.
q. MAS Agwork do not apply or store any 2,4-D for the period 1st October to 30^th April in a given season. So I can see no reason as to why they would contaminate any farmers agricultural chemicals.”

Whilst I hesitate to say this, because as I have already observed that Mr Bell's attitude and approach when in the witness box in the presence of his colleagues was very different, I do think that by the time he had completed his Report, Mr Bell had lost objectivity to the extent that he felt it appropriate to form an opinion and put it in his Report that he felt it was highly possible that the Plaintiff deliberately added 2,4-D to the residue in the shuttle because the Plaintiff was looking for a “culprit" so that it could recover damages.
That is an extremely serious allegation which involves suggestions of fraud, perjury, and some sort of conspiracy to pervert the course of justice, none of which was put to any of the Hardys or Mr Hay, and no submission to that effect made by counsel for the Defendants, all of which was entirely appropriate. I consider Mr Bell's Report to have been the product of an attempt to advocate strongly against the Plaintiff's case in favour of the Defendants by making serious allegations based on nothing more than speculation. Having satisfied himself that it was highly probable that the Plaintiff deliberately added 2,4-D to the residue in the shuttle, there is a real risk that his judgement and objectivity as to other matters about which he is an expert became clouded.
As a consequence, on the few areas where Mr Bell, Mr Somervaille, and Mr McGuinness disagreed, I tend to prefer the evidence of Mr Somervaille and Mr McGuinness.
The general topics and issues raised by their evidence and my findings about those issues were as follows.
Firstly, there was agreement that 2,4-D is extremely toxic to young cotton and does cause significant and ongoing damage because it damages the DNA of the plant itself, which means that all new growth after contact is deformed.
Second, there was dispute between the experts as to whether the symptoms observed and described and seen in the photographs are demonstrative only of 2,4-D poisoning.
Both Mr McGuinness and Mr Somervaille consider that it is and explained why 2,4-D damage is extremely distinctive. Mr Bell does not agree. Whilst he accepts that the damage observed to the crops is consistent with poisoning by 2,4-D, he says it is also consistent with poisoning by chemicals other than 2,4-D, including what is contained in Agixa and others, which he said could be explicable by use of those herbicides on adjoining paddocks, either within the Plaintiff's operation or from adjoining landowners.
The evidence given was detailed and complicated but, on balance, I am persuaded that the observations made as to the damage caused to the plants is consistent only with 2,4-D poisoning. I accept the evidence of Mr McGuiness and Mr Somervaille to the effect that the symptoms are very distinctive.
Third, Mr Bell concludes that, whatever poisoning occurred to the Plaintiff's crops, it is more likely to have been the result of “spray drift" from spraying operations conducted either by the Plaintiff or others and not by the aerial spraying conducted by the Defendants.
His reasoning for this is that, fundamentally, he assumes as a fact that the damage was not uniform at the time it was first observed. For this assumption, he relies on contemporaneous documents prepared by Mr Hay during his weekly inspections where Mr Hay did not record that the damage was uniform and expressed his own view at the time that spray drift may well be the cause.
I have concluded based on the direct evidence from the Hardys and Mr McGuinness that the damage was uniform in the sense that it is only to be found in the specific areas the subject of the Defendants’ spraying, with the exception of the shadow around the haystack area. It is also uniform in that the damage occurred at the same time to all the affected cotton. I accept the evidence of Mr Somervaille and Mr McGuiness that, as a matter of science, the timing for symptoms to become apparent is variable and, because of that, it is plausible that uniformity would not necessarily be noticed immediately by someone like Mr Hay.
As Mr McGuiness, Mr Somervaille, and Mr Bell all explained, lack of uniformity is often demonstrative of spray drift, because it is possible to work out from the spread of damage from which direction the spray drift came. Mr McGuiness and Mr Somervaille both said that none of that indicia was observable here, to which Mr Bell could not disagree because he is relying only on Mr Hay’s contemporaneous notes.
There is also the evidence of Mr McGuinness, which I accept and indeed I think this was accepted by both Mr Bell and Mr Somervaille, that the uniformity of the damage is also consistent with all of the damage, the subject of the claim, having been occasioned at the same time. This is inconsistent with spray drift. In any event, as a matter of common sense, the various damaged areas are spread out over a large geographical area, being 15 km away from each other, and there is no suggestion that the adjoining landowners were the same people, or that they were spraying at the same time. Accordingly, I think I can comfortably rule out spray drift from adjoining landowners. At the risk of being repetitive, I am satisfied that the damage to the crops was uniform and occurred co-extensively with the areas sprayed by the Defendants.
Mr Bell also points out that it is possible that later spraying by the Hardys themselves over those same fields could have caused the damage and is very critical of the Plaintiff's recordkeeping, in that it is not possible from those records to work out precisely where and when they sprayed. Mr McGuiness and Mr Somervaille are both of the view that the damage is observable in such a way that it is possible to tell when it occurred, which they consider to have been in November, which is when the Defendants did the spraying.
There is no doubt that the Plaintiff regularly carried out a lot of spraying all over their property. I also do not doubt that it conducted spray operations on the fields, the subject of this claim, after the Defendants’ aerial spraying.
In light of my findings as to uniformity both as to shape and timing of damage, I think it is highly unlikely, to the point of close to fanciful, that the Plaintiff sprayed exactly the same areas which were sprayed by the Defendants, including by not spraying the shadow area around the haystack (which would not be something required to do if the spraying was taking place from the land) and only spraying the strip that I have described in field 208(2).
It was not put to any of the Hardys, nor Mr Hay, that this occurred, nor can I imagine any particular reason why it might occur. It is, of course, a possibility, but I think it very unlikely, especially as to the timing of the damage to have commenced, that spraying from the ground would have had to have occurred very shortly after the aerial spraying, which I consider entirely unlikely as, apart from anything else, it does not make any financial sense.
I conclude that I am satisfied on the balance of probabilities that the damage was uniform, was consistent with 2,4-D damage, and was co-extensive with the areas sprayed by the Defendants. Whilst it is possible that the Plaintiff’s subsequently sprayed precisely the same fields with contaminated herbicide, I consider that possibility to be unlikely to the point of implausible. I also do not consider spray drift from neighbouring properties or by the Plaintiff itself spraying adjacent fields or the fields themselves, to be a plausible explanation.

The Defendants’ answer

The Defendants seek the following findings of fact:

The damage observed was not uniform as alleged and is consistent with spray drift or spraying by the Plaintiff.

The Defendants kept very good records of their use of chemicals in accordance with the various regulatory requirements.

The Defendants ran and run a professional operation where all of its staff are properly trained in the use of chemicals.

The Defendants records demonstrate that no 2,4-D was on its premises at the time of the relevant flights.

Leaving aside foul play or deliberate sabotage, it is extremely difficult to understand how 2,4-D could possibly have got into the shuttle whilst in the custody of the Defendants by some sort of human error.

The CCTV footage of the various loadings of planes, the subject of the Defendants’ work, is demonstrative of care being taken and there is no suggestion of any other product being poured into the shuttle in those videos.

As to the first matter of uniformity, I have already determined that, contrary to the Defendants’ submission.
All of the other points are well-made points. Each proposition is consistent with the evidence, and they all cast doubt on the inference contended for by the Plaintiff.
I accept that, whilst the paperwork of the Defendants is not perfect, some apparent discrepancies were pointed out by counsel for the Plaintiff, that in large part it does appear that the Defendants were doing their very best to abide by what are obviously complicated regulatory requirements. I also accept that the staff of the Defendants were adequately trained in the use of chemicals and that, on the Defendants’ business records, it does seem unlikely that any 2,4-D was actually in the premises at the time. That does not mean that mistakes could never have been made. There is evidence of one similar mistake having been made by the Defendants in the past. I do not consider that reflects poorly on them but simply mention it as an example that mistakes sometimes do happen, even with the best systems in place.
I also find it extremely difficult to visualise or even imagine how a mistake by a person could have occurred so as to add 2,4-D to the shuttle.
All of those findings stand against the ultimate inference sought by the Plaintiff. However, if the damage was caused by 2,4-D and it is specific to the areas sprayed by the Defendants, it does become necessary to identify a plausible explanation, other than it coming from the Defendants’ plane.

Resolution

The matters that I am satisfied about are as follows:

On the balance of probabilities, 2,4-D did poison the cotton;

On the balance of probabilities, that poisoning occurred uniformly across an area co-extensive with the fields that were sprayed by the Defendants and is uniform in the sense of timing;

On the balance of probabilities, that uniformity is inconsistent with a competing explanation, being spray drift;

On the balance of probabilities, that uniformity is inconsistent with the Plaintiff themselves having sprayed the same area at a later date and unintentionally adding 2,4-D to the chemicals.

the liquid was likely to have been yellow at the time of collection, which is suggestive that it was contaminated before spraying and is demonstrative of 2,4-D contamination; and

that something that emanated from the sample taken from the shuttle at Hardy Irrigation found its way to the testing laboratory and was the subject of the positive test for 2,4-D.

The most significant of these findings are the ones concerning uniformity. A commonsense conclusion from those findings is that the toxin probably came out of the Defendants’ plane. On top of that, I have what I consider to be the real possibility, short of probability, that the liquid was yellow on 13 December and that the sample tested came from the residue. The question becomes does the combination of all of those matters become sufficient to justify the inference sought by the Plaintiff?
I have considered the competing theories or inferences suggested by the Defendants and am satisfied that, even though they are all possibilities, they are much less likely explanations than the one contended for by the Plaintiff. I include in those other theories spray drift from adjoining properties, spray drift from spraying by the Plaintiff of other fields, subsequent spraying by the Plaintiff of the same areas, accidental poisoning by the Plaintiff, or deliberate poisoning by someone else. I put to one side deliberate manipulation of, and giving deliberately false, evidence by the Plaintiff and Mr Hay. That theory was never put to them and is not supported by any evidence.
There are the matters of fact that I have found which do not support a finding that the Defendants sprayed 2,4-D on the Plaintiff’s cotton. The first is there is a lot of evidence, largely uncontested, that the Defendants at the time had in place what appear to be reasonably rigorous systems for preventing this very type of thing from happening. There is a lot of paperwork, involving checklists to be filled out by both the pilot and ground crew confirming that the correct chemical had been loaded onto the plane and that, before it was loaded on the plane, the tanks in the plane had been appropriately decontaminated or rinsed out.
I have also seen six examples on CCTV footage of the Defendants’ plane being loaded with chemicals, the subject of the relevant spraying. What can be observed on those videos does not suggest any lax approach by any member of the Defendants’ staff, nor is it possible to discern from that footage how such an error could have been made.
The second and related point which I think has real merit and weight is that this is a situation where the Plaintiff, not only cannot point to evidence as to how the Weedmaster became contaminated with 2,4-D, but also is unable to hypothesise as to a scenario where that could have happened.
At a practical level, for it to have happened someone must have unscrewed the lid on the top of the shuttle and then poured a reasonable quantity of 2,4-D from a different container into the Weedmaster. Absent malicious intent, which is a possibility but is not suggested here, it is very difficult to visualise or imagine how that could have happened.
Mr Catlin, on behalf of the Defendants, has emphasised that the Plaintiff, if it had taken a more detailed and forensic approach to its investigations, could have adduced better evidence. For example, the chain of custody evidence in relation to the taking of the sample would not have been so productive of doubt. Another example is the Plaintiff could have, but did not, take tissue samples from the plants and soil which may well have confirmed the presence of 2,4-D. Another example is the Plaintiff's apparent poor record-keeping as to its own spraying operations, which make it impossible to challenge the Plaintiff's evidence that they did not spray any herbicide with 2,4-D in it nearby. Finally, Mr Hay’s initial observations could have been much more precise, and he could have plotted on a computer program precisely where he made each observation and taken photographs from those spots, which photographs could have been identified by reference to a map.

All of those observations are true. The Plaintiff could have marshalled and presented better and more cogent evidence. However, I think it is important to step back and appreciate that, during the early stages of the Plaintiff trying to work out what caused the damage, the Plaintiff did not and had every reason not to suspect the Defendants might be responsible and were naturally more inclined to suspect spray drift. Moreover, neither the Hardys nor Mr Hay are forensic detectives, and they did not understand at the time that what they were doing was putting together some sort of brief of evidence for use in a subsequent court case.
What all that means is that the Plaintiff could have marshalled better evidence to prove its case but did not carry out the relevant investigations at the time to allow it to do so.
That is a relevant factor to take into account when assessing the overall weight of the Plaintiff's evidence but if, at the end of the day on the evidence that has been deployed by the Plaintiff, which is the best evidence available to the Plaintiff, is sufficient, then the fact that the Plaintiff could have, if it had investigated the matter differently, proved the same matters by different and better means is no reason to not make a finding in favour of the Plaintiff. This is not the situation contemplated in Blatch v Archer (1774) 1 Cowp 63, which applies in circumstances where the Court knows a party seeking proof by way of inference has better and more direct evidence available, but instead seeks to rely on inferences. In this case, the Plaintiff has put before the Court the best evidence it has.
I have not overlooked the submission made by the Defendants, based on cases such as Briginshaw, that serious findings of misconduct ought not be lightly made or based on inexact proof. That submission rather overstates the Plaintiff’s case. There is no suggestion of misconduct or gross negligence. Rather, the high point of a finding in favour of the Plaintiff would be that a mistake has been made.
Taking all those matters into account, I am satisfied on the balance of probabilities that the Defendants, for reasons unknown, somehow mistakenly loaded Weedmaster contaminated with 2,4-D on to its plane, which was subsequently sprayed on the Plaintiff’s fields, causing it loss and damage, in that the yield of cotton from those fields was reduced.

The legal consequence of that finding

I think it self-evident that the consequence of that finding is that the first Defendant will be liable to the Plaintiff for breach of contract. The contract called for Weedmaster, not contaminated Weedmaster. Regardless of fault, to spray 2,4-D on the Plaintiff’s fields was a breach of contract.
There is then the question of the Damage by Aircraft Act.
For relevant purposes the second Defendant was the “operator” of “the aircraft” for the purpose of the Act at the time the contract was performed. The first Defendant was the “owner.”
Section 10 is in the following terms (my emphasis):

“10 Liability for injury, loss etc.
(1) This section applies if a person or property on, in or under land or water suffers personal injury, loss of life, material loss, damage or destruction caused by:
(a) an impact with an aircraft that is in flight, or that was in flight immediately before the impact happened; or
(b) an impact with part of an aircraft that was damaged or destroyed while in flight; or
(c) an impact with a person, animal or thing that dropped or fell from an aircraft in flight; or
(d) something that is a result of an impact of a kind mentioned in paragraph (a), (b) or (c).”

Section 11 is in the following terms:

“11 Recovery of damages without proof of intention, negligence etc.
Damages in respect of an injury, loss, damage or destruction of the kind to which section 10 applies are recoverable in an action in a court of competent jurisdiction in Australian territory against all or any of the persons who are jointly and severally liable under that section in respect of the injury, loss, damage or destruction without proof of intention, negligence or other cause of action, as if the injury, loss, damage or destruction had been caused by the wilful act, negligence or default of the defendant or defendants.”

Relevantly, the Act imposes a strict liability on owners and operators of aircraft for any damage caused to any person or property by “an impact” with a “thing” “dropping” or “falling” from an aircraft.
Section 11 picks up consequential economic loss from such damage if that loss is as a result of that impact.
Uninstructed by authority, I would doubt that the legislation was designed to capture a circumstance of crop-dusting where what is happening, as a result of a contractual arrangement, is that chemicals are being “dropped” or are “falling” from an aircraft, which chemicals are “impacting" on crops by landing on them, all of which is happening because the owner of the crops has asked the owner/operator of the aircraft to spray chemicals on his or her crops. The “accident” being the incorrect chemicals being sprayed. In other words, the “dropping” or “falling” was not accidental. Rather, what was “dropped” or “fell” was accidentally the wrong substance.
The person upon whom the chemical drops or falls in those circumstances seems to me to be at the very outer edges of the type of “third party” intended to be protected by the Act because such circumstances will be adequately dealt with by the combined effect of the law of contract and negligence. In the Second Reading Speech to Parliament (Second Reading Speech, Damage by Aircraft Act 1999 (Cth), The Minister, Mr Vaile, House of Representatives, Wednesday 24 March 1999, Hansard 4163), the Act was said by the Minister to be intended to protect innocent parties on the ground from damage caused by “air accidents” or “crashes.” In that context, a mistake made in the chemicals sprayed by an aircraft, as opposed to where they have been sprayed seems incongruous.
The Court of Appeal in Bootle, which was a crop-dusting case concerning spray drift onto adjoining properties, determined that s 10(c) and (d) did apply to circumstances of chemicals from crop-dusting aircraft.
The holding of the Court is at [58] in the judgment of Sackville AJA, with whom Meagher JA and Ball J agreed. The reasoning, which is to say the least sparse, is in the following terms:

“The primary Judge was correct to conclude that the DA Act applied. It follows that the challenge to the holding that MVAS was liable to the Barclays under the DA Act fails.”

His Honour’s (the primary Judge, Williams DCJ) findings are summarised by Sackville AJA at [19] of the Court of Appeal’s judgment, which do no more than set out in terms ss 10 and 11 of the Act. The result in Bootle is supported by the Court’s holdings as to negligence, and I am not sure that the statements as to the Damage by Aircraft Act strictly form part of the ratio decidendi of the decision. The proposition of law by the Court that I have set out above is clear but, on the facts of that case, are limited to applying to circumstances of spray drift from crop-dusting onto property not owned by the person who contracted for the crop-dusting.
A much more reasoned analysis is found in N M Rural Enterprises Pty Ltd v Rimanui Farms Ltd [2013] NSWSC 309, per Harrison J at [1080]-[1100]. Notwithstanding my doubts, I consider his Honour’s conclusions, albeit again in the context of spray drift onto neighbouring properties, to be clear, well-reasoned, and cast in broad terms. His Honour’s conclusion is at [1099]-[1100] in the following terms (my emphasis):

“1099
In my opinion there is nothing in the words of the relevant provisions that limits liability to things that cause damage as the result of having inadvertently fallen or dropped from an aircraft. The Act does not say so and it is not necessary to read the words of the Act in that way in order to give it effect. Indeed, the dictionary definition of the word "drop" upon which Lloyds relies includes "to let fall". Such a construction would appear clearly enough to include both intentional and inadvertent acts. It would in my opinion extend to the act of intentionally discharging herbicide from the spray nozzles of the Gwydir Air planes.
1100
Nor do I consider that Lloyds' position is improved or changed by arguing that the Act only applies to accidents and that the damage to the Telleraga crops was not caused by an accident if the glyphosate was discharged intentionally. The accident that putatively caused the damage was the impact or contact with the cotton growing on Telleraga. The glyphosate was deliberately discharged with the intention of causing damage to plants on Boonaldoon. It was not deliberately discharged with the intention of causing damage to cotton plants on Telleraga. Even assuming that it were Parliament's intention that s 10(1)(c) should not apply to an act of deliberate discharge with the intention to cause damage, the damage to the Telleraga cotton was accidental.

Like Bootle, His Honour’s decision concerned a claim by a neighbour that it had suffered damage by spray drift from crop-dusting intended for adjoining land. That is an important distinguishing factor, but I think his Honour’s reasons are cast in such emphatic and broad terms so as to capture the facts here in a way that I should apply unless I considered the conclusion to be clearly wrong. Whilst I may not have come to the same conclusion myself, I do not consider his Honour’s observations to be obviously wrong. Apart from anything else, they have clear support from the language of the Act. They are well reasoned and by a highly respected and experienced Judge of the Supreme Court of New South Wales. I consider I must apply that reasoning to the facts as I have found them.
I conclude that both Defendants are strictly liable, regardless of fault, under the Damage by Aircraft Act.
Turning then to the alleged negligence of the Defendants.
The findings I have made of breach of contract and liability under the Damage by Aircraft Act are arrived at without any finding of any fault by the Defendants. Those legal routes to liability impose a strict liability. The same cannot be said for the alternative claim in negligence.
As I have said, I have no problem with the alleged duty being made out. The question is whether breach is established simply by demonstrating the end result.
The Plaintiff relies on the principle known as “res ipsa loquitur”, which really is an evidentiary presumption created in circumstances where an event happens that, absent some sensible explanation emanating from the person in control of the event at the time, can only be explained by a breach of duty of care by that person.
As explained in cases like Scott v London St Katherine Docks Co (1865) 159 ER 685; Mummery v Irvings Pty Limited (1956) 96 CLR 99 at [114]; and GIO (NSW) v Fredrichberg (1968) 118 CLR 403, the principle is to the effect that, if in the ordinary course an event could not happen if the person in control of the situation had exercised proper care, then an inference is available as an evidentiary matter that the person did not exercise proper care.
I have already said that I cannot envisage how what I think occurred happened. I consider the most likely explanation is something went wrong in the Defendants’ system when the Weedmaster was under its control in their premises. However, it is conceivable that may have occurred through no fault of the Defendants. It is possible that some person unknown interfered with the shuttle. If that is what occurred, then there would be no breach of duty by the Defendants, because, on the evidence, they are extremely careful in their handling of chemicals. I think that possibility is unlikely, but I cannot rule it out.
Accordingly, I do not think the “res ipsa loquitur” doctrine in this factual circumstance assists the Plaintiff. Whilst it is likely that the explanation is a breach of duty of care by the Defendants, that is not the only plausible explanation.
What that means is that, if I am wrong as to the application of the Damage by Aircraft Act, the claim against the first and second Defendants in negligence would fail.

Conclusion as to liability

For those reasons, I consider both Defendants to be liable for damage caused to the cotton crop by the Defendants. The first Defendant based on breach of contract and both Defendants based on the strict liability imposed on owners and operators of aircraft by the Damage by Aircraft Act.

Damages

The Plaintiff puts its damages case simply. It compares the yield of cotton measured by bales per hectare from the damaged fields by reference to field 192 (4) which was not sprayed but is obviously nearby and therefore was subject to the same weather and farming conditions. It was also planted at the same time as the affected areas.
Field 192 (4) yielded eight bales per hectare, whereas the subject fields yielded 4.95 bales per hectare.
The affected fields were farmed after the crop dusting took place in the way they would otherwise have been, were harvested in the usual way, and then sold to market.
The amount calculated by Mr McGuiness is $631,596.40, being the difference between the proceeds of the sale of the actual cotton against a hypothetical sale at eight bales per hectare.
Mr Bell criticises this approach, pointing out that there would have been some cost saving by the very fact that the yield was reduced. The only saving he could point to was the cost of transport to the mill, which he accepted would be small but would also be a saving. Mr McGuiness accepted that cost would have been saved, however, observed that more bales themselves reduce cost pro rata, which he has also not taken into account.
Mr Bell also criticises the approach because he says that the “comparable paddock” – i.e. comparable field (192(4)) – is not a safe comparator and that a better approach is to use as comparable yields the average yields for all cotton farms across the region.
On that approach, he quantifies damages at $299,896.19.
On behalf of the Defendants, Ms Hinchliffe, solicitor, made very careful and helpful submissions to the effect that perhaps both Mr McGuinness and Mr Bell have adopted the wrong methodology. In her submission, a better forensic method would be to take the history of the farm overall over a five-year period and use that as a comparator. She says there is a well-known formula used by forensic accountants being “Y x X x DPN”, where Y is the estimated crop yield for a whole farm, X is the actual yield, and DPN is the dollar per bale.
I have a feeling that methodology is probably a better one, but it was not used by either party’s expert. They both agree that it is appropriate to approach the matter by working out the best comparable and then to compare the actual yield from damage paddocks against that comparable. They agree as to the methodology and agree that damages can be properly assessed using that methodology. They disagree only as to what to use as a comparison against actual yield.
I accept the experts as to methodology, albeit I am sure that there are other, perhaps better, methodologies of proof. In my view, accepting that there are real limitations in picking one field in a particular farm, that field is adjacent to a number of the fields the subject of damage and I think it is probably a better comparable than the average overall for the region, especially in light of the clear evidence from both Mr Hay and Mr Somervaille that the season was a particularly bad season in the region because of weather events, which caused many farmers to not plant cotton on time. However, the Plaintiff did plant on time and therefore did not suffer from that disadvantage.
On balance, I consider that the comparable used by Mr McGuiness is the more appropriate of the two.
The experts agree that whatever reduction of costs there may have been because of reduced transport costs would be minimal. I am satisfied that whatever cost savings there might have been were probably counterbalanced by increased pro rata costs because of the same reduced yields. Nonetheless, to give the benefit of the doubt to the Defendants, I propose to reduce the damages award by 10%, being $63,159.64, thus reducing the damages to $568,436.76.
I am satisfied that the damage caused by the Defendants to the Plaintiff's cotton crop ought be quantified at $568,436.76.
The Defendants ought pay interest on that amount from the midpoint of 2023, being my estimate of when the Plaintiff would have received payment for the cotton crop. That is interest at the Court rates on $568,436.76 from 30 June 2023 to 26 September 2025, which I calculate at $105,081.38.

Orders

For those reasons, I make the following orders:

Judgment for the Plaintiff against both Defendants in the sum of $673,518.14, inclusive of interest up to 26 September 2025.

The Defendants are to pay the Plaintiff’s costs of the proceedings.

**********

Decision last updated: 26 September 2025

Medium Neutral Citation:	Hardy Irrigation Pty Ltd v Leeton Aerial Ag Pty Ltd [2025] NSWDC 389
Hearing dates:	15 – 19 September 2025 (Albury)
Date of orders:	26 September 2026 (Sydney)
Decision date:	26 September 2025
Jurisdiction:	Civil
Before:	Newlinds SC DCJ
Decision:	(1) Judgment for the Plaintiff against both Defendants in the sum of $673,518.14, inclusive of interest up to 26 September 2025. (2) The Defendants are to pay the Plaintiff’s costs of the proceedings.
Catchwords:	AVIATION — Crop dusting — Statutory liability — Damage caused by aircraft while in flight — Strict liability imposed by Damage By Aircraft Act applies to damage caused to crops by crop dusting using incorrect herbicide BREACH OF CONTRACT — NEGLIGENCE — Crop dusting — Allegation that Defendants sprayed Plaintiff’s cotton with herbicide contaminated with 2,4-D, which is toxic to young cotton, causing the Plaintiff loss and damage — Finding of breach of contract and liability under the Damage by Aircraft Act based on inferences — No breach of duty of care established DAMAGES — Proper measure of damages to be awarded for economic loss occasioned by damage to particular cotton fields
Legislation Cited:	Damage by Aircraft Act 1999 (Cth) s 10; s 11
Cases Cited:	Blatch v Archer (1774) 1 Cowp 63 Bootle v Barclay [2013] NSWCA 142 Bradshaw v McEwans Pty Ltd (1951) 217 ALR 1 Briginshaw v Briginshaw (1938) 60 CLR 336 GIO (NSW) v Fredrichberg (1968) 118 CLR 403 Mummery v Irvings Pty Limited (1956) 96 CLR 99 N M Rural Enterprises Pty Ltd v Rimanui Farms Ltd [2013] NSWSC 309 Scott v London St Katherine Docks Co (1865) 159 ER 685
Category:	Principal judgment
Parties:	Hardy Irrigation Pty Ltd (Plaintiff) Leeton Aerial Ag Pty Ltd (First Defendant) JN Aviation Pty Ltd (Second Defendant)
Representation:	Counsel: S Burt (Plaintiff) J D Catlin / S Hinchliffe (Solicitor) (First and Second Defendants) Solicitors: Litton Legal (Plaintiff) Princeton Legal (First and Second Defendants)
File Number(s):	2024/163058
Publication restriction:	Nil