We follow up with another blogletter 19 so soon because Valda Muller informs me that their operation is about to air on Country Calendar sometime in June, probably the 21st. And I know you don’t want to miss that. Her letter below…
This letter also includes snippets of conversations, edited for brevity, that I have not had room to include before.
Thank you again – it is always good to hear that things have gone well for one when for us it has been a very difficult season – there is still hope there at the end of the tunnel!
All the best to you Nick
We were frosted again this season – after a 4.6 degree average increase in July temperatures and warm spring the trees were all set for an early start to the season when hit by severe frosts during the last week of Oct/first week of Nov – diary notes from last year confirmed that the trees were at exactly the same stage of leaf burst and male tassel exposure as when we were hit in 2013 ….. With exactly the same results! Grrr! After 25 years of getting trees to this stage it would be nice to get the crop!
(To compound our woes our cash crops grown to support the nut habit also struggled – a virus into the garlic caused stunning bulbs to collapse 4 weeks after harvest and December and January were so cold that the hothouse was kept closed almost the entire month and at one stage I thought our heritage tomatoes MIGHT be ripe by Christmas 2014 and most plants still have significant crop yet to ripen (??!!) – all in all a season to forget.)
At least we learnt a little from last years experience and I was out with compost tea sprays each morning to the walnut trees post the frosts and we managed to maintain the trees in a much better state of health and have foliage return much earlier than the previous year – so hopefully …….
Recommendations out of all of this would be for our area to select cultivars which are very late leafing out – we have found that our G26 and Franquette cultivars were not affected this year and cropped well. We have also found that choosing a good cultivar for root stock and ensuring it is really vigorous is of utmost importance. Good cultivar trees on poor root stock will not “recover” and make up growth …….like us you could be pulling them out as hopeless 15-20 years later!!!!
A general comment re the use of compost teas – I have observed significant increase in foliage size and depth of colour following the use of the teas and we also had an increase in weight of nut yield/tree (2012) with a larger proportion of nuts being in the bigger size gradings ……. Of course it would have been nice to have verified this through crops in the last two years! There is always more than one variable in farm management so I cannot yet say it is the compost teas that has led to this change.
We still have a very low technology approach to nut drying – with a household log burner in a concrete bunker with fans and an expelair to remove moist air – the nuts are placed in a single layer suing stacks of bread crates. A bit of handling but it is all “woman’s sized” and manageable – and surprisingly efficient in terms of throughput and rotation. I will shift the nut grader into this area so that I have the larger nuts on their own trays and can leave them the extra couple of days to finish off the drying.
Otto’s harvester works well – but we planted with this form of mechanical harvesting in mind. (It really needs level ground, appropriate spacing and pruning). He is keen now to have a business develop the prototype and make it available commercially as this is beyond our current resources. Interested parties can contact Otto. The beauty of the harvester is that ripe nuts are collected direct to bins – so there is no washing required and not the daily collection of nuts from the ground is largely avoided.
I am hesitant to mention this (as I will probably be hiding over the Nevis on the day!) ….. But if any walnut growers out there are interested in our harvest and shelling processes the Country Calendar team visited at this stage. I have been told the programme will probably go to air on the 21st of June. They were a great team and I am sure they will make the most of it – had thought the focus was going to be more on Otto and his mechanical inventions ….. But the timing was not good as he went off to the Treecrops Conference and came back to the second day of filming pretty tired to two very cold days! There may be something there of interest to some growers.
Yields per hectare
I got your email from the report on the Walnut trial in The Tree Cropper journal. I am looking for yields of nut crops in NZ per hectare (and overseas yield data also) to compare nut cropping with other farming systems.
I am making a case for tree based land use as a sustainable shift in NZ agriculture.
I sent him the trial results in a bit more detail. The trees were planted at 10 metre spacings. At this age they would have yielded the same per tree if they had been planted at 5 metre spacings or closer. So for Shannon with 13.6 kg of nuts per tree in 2013 at age 15 would have equated to 1.36 t/ha at 10 metre spacing, and 5.4 t/ha at 5 metre spacing. Rex at 8.6 kg per tree would equate to 860 kg/ha at 10 metre spacings, and 3.4 t/ha at 5 metres.
You are right to concentrate on yields per hectare. It is the single most important factor holding back walnut cropping in NZ. Our mature stand of unselected seedlings is only giving 1200kg/ha, while our best crop has been 2.5 t/ha for 16 year old ‘Roadside 12’ trees.
Australian research (can be viewed on rirdc.infoservices.com.au/items/00-100 ) in an article titled “High yields and early bearing for WALNUTS” starts with the sentence, “The aims of the project were to raise the yield of quality walnuts from 1.5 to 4t/ha…”
Figures from the Sun Diamond Grower News ( no longer available online without a password.) for Summer 2008 talked about average crops for newer plantings of 5, 000lb per acre. (5.6 tonne/ha) Older orchards were said to be yielding 1,500lbs /acre. (1.68t/ha). The summer 2010 Grower News quotes per-acre yields for China of 500 pounds.(0.56 t/ha) But I have heard of a Chinese research block claiming to get 6 tons/acre (14.5t/ha). [I think that must have been 6t/ha actually.]
How do you fare on this scale? Email me with your successes and frustrations……
Spotted; this advert in Papers Past: Waikato Times, 23 July 1892, p. 3
Large French Variety.
A limited number of Well-grown Three-year-old Walnut Trees of the above variety for sale. Apply to C. H., c/- Waikato Times Office, Hamilton.
Wonder if they were Franquette?
Cheers Kathryn M
Many thanks for latest blogletter (16). So interesting to hear about walnut growing in China and Jeffreys account of his visit there.
Let’s hope that some of the disease problems that they face don’t find their way here too quickly!
On a personal note, we have about a dozen trees ( mostly grafted varieties) ,planted over the last 30 years, and for home nut consumption. However, as furniture maker, I’m keen to know a bit more about pruning for timber. If there is anyone who can offer advice ( about when best, painting cuts, avoiding bleeding etc. )I would be very grateful. Also I’ve used walnut timber from a number of different walnut trees in our locality (Wairarapa), and the colour of the wood varies
Following on about the variety of timber colours in locally grown trees, I was wondering about the cause. The heartwood in them seems to vary from very dark, almost black, grain through to really pale. Different soil with the different locations? They all looked like Regia, but different varieties? I’ve had a Black walnut tree too ( Nigra) and that had the usual purpley / brown heartwood, similar to the imported stuff from the USA.
Many thanks, Jeremy B
As you may know, my whole project is about growing J.regia for timber (+the nuts). You are asking the same questions I am.
Firstly, about the heartwood. I wish I knew what caused the colour. We thin to waste regularly, and I have yet to find a tree with any coloured heartwood. I am hoping that that is just an age thing. A couple of months ago we cut 2 trees up for sawntimber. I wasn’t surprised that there was no dark heartwood, though the trees were 35 years old with a dbh of about 35cms. If you are using walnut timber from different sources, maybe you are in quite a good position to take note of the environment of the tree and compare it to the colour?
Pruning is quite simple. Trees bleed from early June to mid December here (BOP). It will not be that different down your way. The bleeding looks terrible, but I don’t think it does too much damage to the tree. U.S. reports on pruning black walnuts say you must make sure no branches reach 2 inches diameter. With European walnut grown in NZ that is impossible. I have come to the conclusion after many years of trial and error that it is better to cut off a big branch than leave it because a big branch deforms the whole stem, and the most important consideration for a sawmiller is a straight stem. My current approach is prune twice a year. I do a whip around in early January to nip any problems in the bud; – branch getting too big, leader lost its way, that sort of thing. Then I do a more aggressive prune after harvest in May. Diana Loader’s rule of thumb is quite useful, “Take at least one branch off every tree.”
The other problem with pruning walnut trees is that they tear badly. So I do a 2-cut approach if the branch is more than a couple of centimetres thick.
The article at the Walnut Symposium about growing walnuts for timber in Spain will be interesting. You should be able to read it on the net before long, as that is what happened to previous symposia.
Good to get your feedback
Thanks for your advice and comments. Much appreciated. I will try and take more note of tree environment in relation to it’s timber colour. However, I have to say, that from one avenue of walnut trees near here, that were quite old and decrepit, there was a big variety of colour difference, and yet the trees looked similar.
I agree you get very little heartwood showing in young trees. Even a 50 year old tree I had some years ago was only about 100mm heartwood.
I fear I’ve missed the boat with pruning this year, and will remember to do it in the autumn. There are one or two I’d like to try and train for a future timber tree . Most, I don’t mind branching out and producing nuts!
Will look forward to the report on the Spanish experience on timber production.
Walnuts Australia cracks the domestic market
Australia’s only large-scale commercial supplier of walnuts has ended nut processing in Vietnam.
All of the nuts grown by Walnuts Australia at Tabbita and Leeton in southern NSW and at Swansea on Tasmania’s East Coast are being shelled, graded and packaged in the Riverina.
Operations manager Derek Goullet say its new $11 million processing plant at Leeton is designed to mimic a hand-cracked product.
“A lot of our customers are accustomed to hand-cracked kernel from our Vietnam process that we utilised. We need to make sure that we’re meeting those customers expectations on what they see, so the kernel they get is unscuffed and as many large halves as we can, to make sure our margins are as high as we can make them.”
The company is now supplying walnuts to Woolworths for its Select brand and expects to pick up new export markets for its Australian processed product.
“There are a lot of export customers that do want kernel, that currently don’t buy our in-shell nuts. Asian markets, such as Japan, is one of those potential markets that we don’t currently supply that we’re looking more and more into.”
The new cracking plant is also expected to reduce the cost of production and limit exposure to foreign exchange rates.
Food Storage moths
Following on from the mention of codlin moth last time, it has been brought to my attention that some people may be confusing it with the food storage moth. They are quite different insects. The food storage moth, also called the pantry moth, is called the Indianmeal moth in America because it was a major problem for the American Indians’ corn storage.
It can be quite a problem for walnut growers, possibly worse than rats. Processors have to be vigilant, and growers who only sell nuts in shell can get caught out as well. And it is sometimes hard to tell if a nut has been infested until you open it.
Eggs: Eggs of the Indianmeal moth appear grayish white and range in length from 0.3 to 0.5 mm. Eggs are oviposited singly or in clusters, and are generally laid directly on the larval food source.
Larvae: There are five to seven larval instars. Their color is usually off-white, but has been observed to be pink, brown or almost greenish, depending on the food source. The mature larvae are about 1/2 inch in length. They have five pairs of well developed prolegs that help them move considerable distances to pupate.
Pupae: The larvae pupate either in a silken cocoon or unprotected. The pupae are 1/4 to 2/5 inch long (6 to 11 mm) and are pale brown in color. Pupation takes place away from the infested material. In fact, the late instar larvae can travel such distances that they are often mistaken for clothing pests. Within the pantry the small larvae often climb to other shelves before pupating. This misleads people trying to find the source of the infestation.
The above comments and pictures are off the ‘net from the University of Florida. But this is my approach to control…
I have found that good hygiene is paramount. The pupae shown in the picture seem to last quite a long time in unobtrusive places only to re-emerge and infect the new crop.
Our aim is to make sure there are no in-shell nuts in any buildings by the end of January. Our personal supplies, to last us over till the next crop, are all cracked and put in the deep freeze. We even do a complete clean out to make sure there are no nuts or broken pieces in corners or behind the driers. I read somewhere that all stages of this insect including the eggs are killed if deep frozen for 4 days. That was put to the test one day when they got out of control at my mum’s place. So we disposed of the obviously infested products, threw all her flour, seeds, spices and other dry goods into the deep freeze, and wiped down all the walls, shelves etc. to get rid of the pupae. It worked a treat.
There does seem to be difference between varieties as to how susceptible they are to infestation. Tight sealed nuts are moderately impervious. Wilson Wonder can have a weak spot at the stalk end, and the new variety Gaudion seems to have a problem too.
Now let us hear how you deal with this troublesome pest.
Enjoy the Muller’s Country Calendar programme,
nick nelson parker
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Walnut Blogletter 17 August 2013
Obviously people enjoyed Jeffrey Feint’s account of his trip to China. This was a sample response: [Read more…] about Walnut Blogletter 17 – August 2013
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by Otto Muller
The two major factors limiting the walnut industry are blight and frost. In Central Otago the area suitable for planting is limited to areas frost-free during the growing season of walnuts, while in Canterbury areas with lower rainfall are preferred because higher rainfall areas are more likely to have problems with blight. David McNeill is working on a rather ingenious project to find a solution to the problem of blight. If he is successful he will have earned the gratitude of walnut growers all over the world because blight is not just a New Zealand problem.
To the question as to who should look at walnut cultivation as a form of land-use, I would suggest that 3 groups would do well to do so.
- There are a large number of 10 acre blocks. In many cases the people have got what they are looking for. However in many cases the owners find that it is too demanding to look after the great variety of farm activities that they are involved. In many cases they are very much in the red financially. Once a walnut orchard is established it does not take too much time to look after it. There would be very few days that one could not possibly go to play golf or go fishing; seldom is there is something on the walnut orchard that has to be done today that could not wait until tomorrow. Where there is a concentration of smaller walnut orchards it will not be long before an enterprising kiwi gets himself the necessary machinery to go contract harvesting. And after the rather long period walnut trees take to come into full production the owners of such a walnut orchard will be pleasantly surprised about the very high returns such an orchard is able to bring in. Since winter is a quite period on a walnut orchard it would be quite feasible to organise an overseas holiday without neglecting what has to be done over the winter.
- A walnut orchard would be a good investment to get a retirement income. It would be necessary to get started about 15 years before retirement. But it would be quite feasible to establish a walnut orchard in the country while working in the city and doing the orchard work over weekend, which would generally involve irrigation and watering. Once the orchard is coming into commercial production it would be a very profitable enterprise that still leaves enough time to do all the things for which there was never enough time during the busy working live.
- There is scope for large plantations of walnuts. The operation can be completely mechanised and as such lends itself to large-scale production. A large Tasmanian company is establishing a 500 hectare block of intensive walnut orchard. They budget for a production of 4000 tons of whole nuts, which at present NZ prices and world prices would be worth some millions of dollars a year. The big problem to many people is the very long period required before the orchard achieves commercial production, which in our country would be some 10 years. This however is not as big a problem as appears at first. The young walnut trees occupy only a very small part of the orchard and there is no reason as to why the ground in between cannot be used (inter-planted) for other crops until the young walnut tree starts spreading out and bring a commercial return. If the proposed orchard is part of a livestock farm there is no need to reduce stock numbers. The area in walnut trees simply would be used to make hay or silage. We found that from year seven we could keep our merino sheep in the walnut orchard without any tree protection. We also found that horses did not do any damage even on very small trees. We only had one horse that did develop a liking for walnuts which turned out to be a rather expensive way to feed a horse.
We did sell a small piece of land for a flower grower who did grow Asian Lilies between the walnut trees. The walnut trees kept on producing nuts normally and the lilies did well. There is no reason one cannot grow a crop of corn, onions or squash and countless other crops until the walnut trees start covering a major part of the ground. Walnut trees are very deep-rooted and in suitable ground will have roots extending to 5 meters depth. As such they are not very much affected by shallow rooted crops, provided fertiliser is applied to cover the need for both crops and there is no shortage of irrigation water. Commercial walnut production is very profitable and there would be very few other crops that would provide a comparable return after costs. Above all among the horticultural crops there would be very few that involve the low level of hassles you have to contend with on a walnut orchard.
We planted our first walnut trees 17 years ago. They were seedlings and have now a trunk of 250mm diameter. The next planting was a trial orchard with 11 varieties of walnut trees.
Among the many varieties the Vina was outstanding from every point of view. I am aware, that Canterbury growers do not find Vina a good nut. This is probably due to the fact that in our microclimate in the Bannockburn area we have some 1250 Degree-days. They like the heat. I found that in the southern district of the San Joachim valley the average yield of the Vina was 7 tons per hectare and these were all young plantations since the variety is a relatively new one. Unfortunately we had a big fire and lost our entire trial block. We have now our new plantation along the lake, which is slowly coming into production. We have a nursery operation with a capacity to plant new blocks at the rate of some 800 grafted trees a year.
We are training our trees to have 2.5 meters clearwood. This does take a few years longer than allowing the lower branches to fruit. Our reasons are:
- Keeping the fruiting branches well clear of the ground keeps them away from any ground frost.
- Keeping the orchard clear of branches hanging down improves air circulation and avoids danger of blight.
- It is possible to provide frost protection in a nursery, while it is not practical to do so at a field level. So we grow trees to the 2.5 meters in the nursery and transplant them, so avoiding frost damage to our young trees.
- We can operate all our machinery under the trees without any danger of having our heads chopped off.
- During our market research we found that the highest price paid for walnut timber was for a tree trunk with a minimum diameter of 65cm at a height of 2.5 meters (standard plywood panels are 2.4m — 1.2m). Last year prices paid for this grade in Germany was $5-6000 per m3. One of my friends who has a large furniture factory in Europe has his own plantation. He grows the trees to 4.5 meters clearwood. He started the plantation because he could not depend on a regular supply of walnut timber. In this way at least his son will not have this problem. We had some visitors from part of the USA where they grow large areas of black walnuts. They told us that they had to keep armed guards on their plantation for 24 hours a day to guard this valuable timber. It is important to realise that if we want to play a part in this highly lucrative timber market, we have to be able to regularly supply substantial quantities of a high class of such timber. I feel that timber grown in the North Island would grow too fast to be acceptable by European furniture manufacturers.
It is quite possible that some varieties of walnuts growing in areas which are generally not considered to be suitable for commercial walnut production could very well have resistance against blight. Nick Nelson Parker at Opotiki has varieties doing well in the area, where our selected varieties would most likely be a failure. I believe that it is possible that this genetic plant material could be important to increase the areas where walnuts can be considered a commercial crop, since they are likely to be resistant to blight.
We have also been busy developing technology to deal with the processing of walnuts. We built a nutcracker to crack nuts with doing minimum damage to kernels and of very high capacity. It is based on a different principle to the ones used in the USA and Europe and we got the process patented.
Here in Central Otago I can see the main limitation to the walnut industry in the very high prices paid for land suitable for growing Pinot Noir grapes. They have the same climatic requirements as our walnuts.
Regarding the walnut industry, I believe that it is important to realise that it is possible to grow crops in between the walnut trees to utilise the ground until we get a commercial return from the trees. I believe the long wait for this return is putting many people off the idea to grow walnuts commercially. In countries in the Balkan it is a usual practice to grow peaches in between the walnut trees until they start producing commercial yields. They grow one row of peaches in between each row of walnuts and one peach tree in between each walnut tree in the rows, peaches start producing commercially after 3 years and it is not unusual in our country to plant peaches for a rotation of some 6 — 10 years. When the walnut trees are staring to cover the ground the peaches are removed. In economic terms a highly productive walnut orchard would be pretty hard to beat with regard to the net return per hectare. What impressed me above all was the ease with which such an orchard can be managed and the absence of most of the hassles that go with most other horticultural crops.
Since I had not heard about this conference I thought I would circulate this email via the blogletter mailing list
All the best
As you no doubt know there is the international conference on walnuts in S-E China this coming June, and I wondered if you had heard of any New Zealanders who are thinking of attending since so far I have not heard of any. I am vaguely thinking of attending since it would obviously be something different to our usual meetings, and might have a bit of tax deductibility.
Valda Muller sent me a note from the Australian walnut industry and they are looking at a tour group although I have not heard back from them whether they would allow any Kiwi travellers as well.
Jeffrey A Feint