Harvest Survey 2024

Many thanks to all the members who took part in the Harvest Survey 2024.

HGANZ undertakes a survey of members (about) every three years. It collects general information about orchards and yields, and feedback from members about how they spend their time on hazelnuts, and what they think needs attention from the Association. This information is used to determine research priorities, and inform grant applications.

Last year we had 19 responses to the survey, and the data is presented here. All names have been removed, and the orchards are identified by region. Where members chose anonymity, the data was removed from individual tables, and only used in aggregate data so that their information couldn’t be identified.

Orchard, tree and yield data is presented in tables and graphs, while wordier responses have been summarised.

Any errors, corrections or comments, please email Christine at cinorobinson7@gmail.com.

Survey ResultsLocation, Size and Age of Orchards

Figure 1 shows the orchard location of survey respondants. Orchards are listed clockwise from north to south, beginning at twelve o’clock.  Nearly three quarters of the orchards are in the lower South Island, from Hurunui District south.


The number of trees in each orchard is shown in Figures 2 and 3, the same information but presented in a different way.  The majority of growers (10/18) farm 1000 trees or fewer.  Four growers were in the mid-range with around 2600 trees. The largest orchard had 7000 trees.

Figure 2

Figure 3

Eleven Whiteheart growers specified which pollinisers they use, and all had two or more cultivars planted.  One grower paired Whiteheart with Tonda Romana and Jefferson, while the other ten used Alexander, and at least one other polliniser (usually Merveille de Bollwiller) but also a smattering of less common cultivars (see Table 1). 

Table 1 Polliniser Cultivars used by 10 Growers of Whiteheart

CultivarAlexanderMerveille de BollwillerButlerJefferson Tonda RomanaLansingWaiauUnspecified
No. of Growers109111131

Growers of Barcelona use more pollinator cultivars, one reported using Ennis, Alexandra, Tonda Romana and Merveille de Bollwiller, while another uses many pollinators and increased the number after observing that pollination was poor when less than 10% of the orchard.

Figure 4 shows the year(s) the orchards were established. Interestingly, most of the North Island orchards were planted after 2010, while most of the South Island orchards were established much earlier.

Figure 4 Year(s) Orchard Established

Survey Results – Yield Data

Overall, it was quite difficult to summarise the data and I would be careful quoting these numbers.  Some people estimated (~), one used <10kg, at least one included the polliniser nuts, while others are precise about the total weight.  One orchard has been progressively pruning the last three years and knew their harvest was lower than usual.  Yield information does not consider the age of the orchard, although I excluded those with young trees.

What do you consider a good yield per tree? (total dry weight in kg)

Two did not know or were unsure, and one was not producing nuts yet.  

Barcelona owners expect between 3-5kg/tree (3 responses).  Whiteheart owners expect between 1 and 4 kg/tree (10 responses, excluded the young orchards).  One said 10kg/tree.

What was the size of your harvest in 2022? (total dry weight in kg).

The total was 25,591kg from 13 responses, which includes Whiteheart, Barcelona and Ennis cultivars.

Whiteheart = 0.8kg/tree (25,168 trees, 20,977kg nuts)

Barcelona = 2.7kg/tree (not reporting because of anonymity)

What was the size of your harvest in 2023? (total dry weight in kg)

The total was 24,032kg from 15 responses, which includes Whiteheart, Barcelona and Ennis cultivars.

Whiteheart = 0.8kg/tree (27668 trees, 21,737kg nuts)

Barcelona = 2kg/trees (not reporting because of anonymity)

What was the size of your harvest in 2024? (total dry weight in kg)

The total was 34,773kg from 15 responses, which includes Whiteheart, Barcelona and Ennis cultivars.

Whiteheart = 0.9kk/tree (17,668 trees, 25,482kg nuts)

Barcelona = 2.6kg/tree (not reporting because of anonymity)

The cultivar Ennis out-performed Whiteheart and Barcelona by a large margin.  Grower requested anonymity so no data presented here.

Survey Results – Losses at Harvest

Do you measure yield loss from field harvest to shipped product? (i.e. blanks, rotten nuts etc.)  If you do, what is the approximate percentage?  

Variable answers as expected and the loss varies from year to year according to the weather.  As a generalised summary, dry summers lead to more shriveled kernels, and wet summers lead to more mould and higher losses.  The Barcelona tip is prone to black mould which is tricky to detect without cracking.  From those who hazarded an estimate, anywhere from 5-20% loss.  Also losses from wind, the previous season cling-ons mixed in with current season, and late nut fall which was not collected.

One member with a scientific mind and young trees, calculated losses of 44% for Whiteheart, 33% for Jefferson and 37% for Tonda Romana.

Survey Results – Pruning, Processing and Orchard Workers

Do you follow a particular pruning style? (e.g. vase, height-restricted, mainstem)

The majority prune to vase.  One member prunes to limit height and two prune to a mainstem. 

Do you sell to a processor, or sell them yourself? 

Ten members sell to a processor.  Two sell some to a processor and sell some themselves, and  three sell all their harvest themselves. 

Do you employ others in your orchard?

The majority (13 members) do not employ anyone in their orchard.  Two employ family and/or friends and two employ seasonal agricultural workers or students.

Survey Results – The Big Issues

What is the biggest orchard issue that you face? And what is the biggest orchard issue that you would like more information about? (orchard management, harvesting equipment, pruning, etc..)

Issues around harvesting were the main problem.  Members found the time required to harvest and sort nuts was difficult to manage alongside other commitments.  One had difficulty completing the harvest within the weather window and another had trouble sourcing spare parts for harvest equipment.  

Low economic returns were a problem, with low yields per tree (especially of Whiteheart). This made it uneconomic to mechanise nut-sorting for at least one member.  

Three members mentioned pruning, one of whom also wanted more information about how pruning affected nut flower initiation.  

Two members found it difficult to source young trees.

Only two members mentioned control of suckers as an issue (surprisingly!).  However, a third would like more emphasis on finding and promoting the use of non-pesticide alternatives to agrichemicals.  

Tree health and management was mentioned by one member, and another would like a soil test but the cost was too high.  Bureaucratic costs were another issue.

One member is interested in converting from diesel-powered harvest machinery to electric.

 And finally – how to detect a bad nut.

What are the 5 most important areas for research for the industry? 

Growers’ Ranked Responses of Research Priorities for the Industry

New cultivars11
Pruning and light interception10
Canopy management for mature trees9
Plant nutrition (soil health and/or fertiliser applications)9
Pollination efficiency/compatibility8
Nut bud initiation6
Sucker control6
Training systems for young trees4
Phenology2

Other areas of research were suggested by members.  

A best-practice guideline for collecting, cleaning and storing hazels would be an advantage.  Ensuring that the orchard floor is clear before harvesting would reduce the number of bad-tasting and unusable nuts.  Also whether washing the nuts is changing the flavour (for the worse, in one member’s experience).  And finally, the correct temperature for drying nuts, one member recommends drying at low temperatures.  

Members would also like to see more promotion and marketing of hazels, and that returns on in-shell nuts have not reflected inflation costs.

Research into the ability of hazels to stabilise soils and survive climate change issues.

Are there any other comments you would like to make?

The big theme is around the low yield per tree, coupled with the low return when selling and lack of NZ-grown hazels in the shops.  Difficult to compete with cheap imports, when consumers do not know and value the taste of a fresh nut.  On the topic of yield, the orchard yield is far below that of individual trees in the back garden, so what needs to change in the orchard to bring yield up?

And the final point took the opposite tack, about where to source large quantities of seedlings if the industry were to explode.

The Puriri Moth Loves Hazels Too

Alison’s property and field trial near Rotorua. Left: evidence of a larval activity, frass is pushed out of the tunnel as the insect larva tunnels into the trunk. Right: Alison cleaned away the frass to reveal the entrance and the damage done to the outer bark. (Photos courtesy of Alison Bentley.)

Turns out, New Zealand’s native puriri moth (Aenetus virescens) loves hazelnut trunks too. Originally thought to be lemon borer, seven of the 62 hazels in Alison Bentley’s trial developed these signs of incursion.

Alison works to organic principles and didn’t use pesticide to kill them. On one tree where the burrow was low on the main trunk, she amputated below the burrow, the tree re-sprouted and she chose three leaders to form the new growth. On others, no action was taken, and the larva didn’t kill the tree, but slowed it down.

Murray Redpath, who lives in the Bay of Plenty, has a lot of experience with puriri moths in his orchard. His property is surrounded by native bush, and at night the puriri moths invade, apparently loving all the exotic trees.

Puriri moths are endemic to the North Island, so they were a novelty for the South Island members. Normally they complete their life cycle in native plants like puriri trees, putaputaweta and kohekohe, but clearly they have taken to the introduced plants like moths to a candle.

Below is the link to the Landcare website which has photos of the larvae inside the trunk of trees (not hazels). The extent of the burrows demonstrates why it is so difficult to kill the larvae, PLUS the larva creates a cap to seal the tunnel while it pupates. [Ed: the photos are copyrighted so I couldn’t copy them over for easy viewing.]

https://interestinginsects.landcareresearch.co.nz/taxa/99ebf990-871a-4515-90e5-a9a93ada8637

Another annoying fact, from the human perspective, is that the caterpillar spends between 5-7 years in the trunk before emerging as New Zealand’s largest moth.

https://www.doc.govt.nz/Documents/getting-involved/students-and-teachers/invertebrate-factsheets/puriri-moth-factsheet.pdf

AGM 2025

The 2025 AGM took place on the 18 June 2025, via Zoom. 

Thank you to everyone who attended, and also to those who volunteered to be on the Committee.  We would like to take this opportunity to thank our outgoing Committee members for their years of service to the Association. We would also like to welcome Les McCracken to our team.

Your new Committee is:

Chair Peter Barrowclough

Deputy Chair Paul Rollin

Treasurer Michael Petherick

Committee Alison Bentley

Kasia Henderson

Les McCracken

Murray Redpath

Deb Whiteside

The formal matters were completed with reports from the Chair (Peter), Treasurer (Michael) and Executive (Christine), and then the new Constitution was voted in. HGANZ is now compliant with the Incorporated Societies Act 2022. The highlight of the evening was Alison Bentley’s presentation of her 7 year Hazelnut Field Trial in the Rotorua Catchment area, funded by the District Council.

All the documents are below:

Link to the draft copy of the 2025 AGM Minutes,

Link to Reports from the Chair, Treasurer and Executive.

Link to new Constitution,

Link R&D document,

Link to Alison Bentley’s hazelnut trial, 

https://www.rotorualakes.co.nz/vdb/document/1978

A Trial of Spraying Nitrate Fertiliser on Hazelnut Suckers in Canterbury

Peter Barrowclough 31 March 2025

At a Hazelnut Growers Association Field Day on 22nd June last year, Assoc Prof Clive Kaiser from Lincoln University told us that he had recently seen overseas the use of nitrate fertiliser to “burn” suckers off, achieving good sucker control.

I decided to experiment with this option.  I have around 2500 whiteheart trees in Canterbury on good soils with irrigation.  They are 17 years old.

I purchased a 20kg bag of 27% Calcium Ammonium Nitrate (CAN) from Farmlands.  I made up a 17% solution in 120 litres of water and sprayed it on my suckers on the 11th of Nov.  It was not very soluble and gummed up my sprayer.  This took about an hour to clean out afterwards.  But I did manage to get the spray on half of my orchard or around 1250 trees. The remaining half of the orchard was sprayed with Buster at my normal rates.  The  CAN appeared to be quite fast in acting and the suckers showed wilting within a day.  I was encouraged.

Early wilting of suckers sprayed with CAN.

However the suckers sprayed with CAN recovered and required a second spray whereas the suckers sprayed with Buster did not.

I was wary of using CAN again because of its insolubleness so I purchased Sulphate of Ammonia.  I made up a 10% solution and sprayed it on the suckers for the same half of the orchard I had tried the CAN on the 30th of Nov.  It was much more soluble and the sprayer did not require cleaning out.

I also sprayed the remainder of the orchard again with Buster on the 7th of Dec to get a fair comparison.

We took an overseas trip during December and I was out of the country for a month.  It was a very wet period with frequent rain giving good conditions for strong sucker growth.

I came back to strong sucker growth on the trees sprayed with  sulphate of ammonia which were now reaching up into the canopy.  Control for the Buster sprayed suckers was better, but not complete.  

Strong regrowth after a month for suckers sprayed with Sulphate of ammonia
Better control for suckers sprayed with Buster during the same time period.

Conclusions.

For those of you that grow Whiteheart you will know that they are prolific suckering trees.  While it would be preferable to control them with a fertiliser rather than an agrichemical, this limited trial would indicate more frequent applications may be needed, or more research done.  Sucker control is a major issue and once they reach up into the canopy they can no longer be sprayed without impacting the tree.  Suckers can then grow up into the top of the canopy restricting light and thus nut formation.  I will be returning to my regular use of Buster for control. 

AGM 2025

The 2025 AGM of the HGANZ will take place via Zoom in June.

This year it is important for members to vote on the adoption of the new Constitution, brought about because of changes to the Incorporated Societies Act 2022. More information about these changes can be found here:

https://is-register.companiesoffice.govt.nz/help-centre/getting-started/new-legislation-for-incorporated-societies

As well as reading and voting on the Constitution changes, now is a great time to consider joining the HGANZ Committee. Small organisations need everybody to stay curious and participate. Apart from Officer positions (President, Secretary and Treasurer) Committee members rarely have a ‘job’, their contribution comes from their experience and different perspectives – and often who they know in different organisations.

Meetings are held on a Tuesday, at 7.30pm on Zoom, and there are six per year.