by Roy Hart

I didn't realise until lately, that Perigord black truffles make a good combination with olive oil. This could be the thing to make the small olive grower profitable.
So far it appears the small scale olive grower will never make enough profit to do more than give a little extra pocket money. All this depends on how you run your operation of course. However, half a hectare of truffles in New Zealand has produced 9 to 20 kg of truffles, and that would be a much more profitable proposition.

Where does olive oil come into this? Well you can infuse olive oil with pieces of truffle and have a much more valuable product. This could lift the profitability of the olives.
Growing truffles is not a five-minute wonder job. It needs thorough planning, and then patience for the crop to begin 9 to 10 years after planting. This is not pie in the sky stuff though, there are truffles being produced already in New Zealand.

State of the Industry with historical perspective

In 1892 France produced 1800/2000 tonnes of truffles per year. This has steadily declined over the years, and was down to 130 tonnes in 1958, 70 tonnes in 1961, and 48 tonnes in 1965. This production was virtually all from traditional areas that were deteriorating through neglect, ignorance and war. Now in a good year 50 tonnes is produced, and in a poor one only 10 tonne.
Because of this situation, the French put a lot of effort into a modern system of cultivation to improve the production of truffles. This has developed to the stage that artificially inoculated trees can now be planted out to establish truffiere in France, and also of cause New Zealand. Truffles are now being harvested in New Zealand.

Although there are several other truffle species that are harvested and marketed, the Perigord Black Truffle is considered the best one, and returns the best prices in the market. The Italians have a white truffle that is good, but is second best to the black one.
Although returns vary widely, they are usually very good. But like everything else quality has a strong influence on returns. From the historical figures there is a large shortfall in production, so there should be no trouble selling them.

Early ideas about truffles

Early ideas about truffles describes their mystery. Pliny described them as "callus's of the soil". Plutarch explained their existence as the result of the combined action of Thunder, Rain, and Warmth of the Sun on the soil. In the sixteenth century they were believed to be the product of semen of rutting deer. By the early nineteenth century, biologists thought they were galls produced by oak roots. Later on there was a famous theory (not of evolution) that the truffle fly stung the roots of the oak trees, causing the galls. This was due to the clouds of flies hovering over truffle beds.

Someone eventually realised that the flies , as well as animals (and humans) are attracted by their scent. This attraction is very strong, and lead to dogs and pigs being used, when trained, to find truffles. This can be hazardous as it then turns into a rush of who gets the truffle first. Truffle growers who use pigs can be recognised through having fingers missing.

The Perigord Black Truffle

Tuber melanosporum is a fungus that produces fruiting bodies under the surface of the soil. They grow in association with tree roots. These are usually oaks and hazels, but sweet chestnut, some pines and various other species can be involved. Oaks are the most important though.
Special conditions are needed for growing to be successful. Optimum requirements are for warm summers and cool winters. Soil should be free draining, well aerated with a well-defined structure. A very high pH is needed of between 7.5 and 7.9. However, this high pH can be achieved by large quantities of lime. You will need irrigation.
The proposed site should have no trees that may have competing fungi on their roots. A good maxim with truffles is moderation in everything.

Inoculated trees are available from Crop and Food, Invermay Research Centre. Unless you're lucky, allow 18 months after ordering to receive the trees. They cost about $50 plus.
This waiting time can be well spent preparing the site with cultivation, and getting the pH and fertiliser spot on. Growing truffles successfully needs a thorough approach to detail.
Dr Ian Hall at Invermay has a book that contains most of the information you need, 'The Black Truffle: its history, uses and cultivation'. I believe it is out of print now, but it is available on the website. *

What districts are most suitable is still an educated guess for New Zealand, but North Canterbury, Hawkes Bay, North Otago and Poverty Bay are likely areas to consider.

Should Tree Croppers have a go?

If genuinely interested you should join the NZ Truffle Association, PB 50034, Mosgiel.

A truly commercial enterprise should obviously consult Ian Hall at first. However, I think it would be nice for cottage industry people to have a go, as a retirement project, or sideline. There is obviously good money to be made from relatively small blocks. Small scale olive growers could turn their small returns into something worthwhile by infusing their oil with truffles. This should secure a good return for both products.

You could fill your weekends searching for black gold, and I could lend you my golden labrador to find them; she's certainly no good at keeping burglars away.

Roy Hart

Resources

* The Black Truffle information is now available on CDROM:

Try this link: The Black Truffle CDROM
Otherwise,
Crop & Food Research website; products, publications, books and CDROMS; quickfind "black truffle"to look for The Black Truffle CDROM "...introduces the general reader to the fascinating world of the black truffle and the delicate, mutually beneficial relationship that forms between this fungus and its host tree..."

Our NZTCA publication 'Basic Notes - Tree Crops in New Zealand' (the Green Guide - tree cropper's FAQ) includes a sheet on truffles.

Our Canterbury Branch plans a field day on Sunday 2nd March 2003 titled The Great Edible Fungi Hunt:

"We are very fortunate to have both Dr. Ian Hall and Dr. Wang from Crop & Food Research to talk to us about their work, show us slides and identify the fungi samples you bring in. In addition, Gareth Renowden will discuss his truffiere experiences, and gourmet aspects of mushrooms. Meadow Mushrooms are donating product to cook up for lunch." More details...

http://www.treecrops.org.nz/knowl/addgen/blacktruf.html
Created: 10/April/2002 - Updated: 2007 July 23