Testing The Trees
Of major concern to all in the industry is ensuring that trees with sufficient levels of infection of the target truffles species, AND those containing NO detrimental contaminant fungal species, leave the nursery. Note that your trees’ root system will almost certainly contain other non-detrimental fungal species. Fungal spores are everywhere, including all over your planting site.
To this end, the trees are being microscopically tested prior to dispatch by Kings Truffles. Trees are only dispatched where they are considered fit for purpose.
The level of infection deemed suitable is fixed by the nursery at or above the industry-accepted standard. As there is still significant dispute within the industry as to what this is and how it is measured, Kings Truffles has adopted the conservative approach.
Cost prevents us from testing every tree as well as it being disruptive to the tree, so a representative and statistically significant sample is taken from each batch. If all of these samples have positive results, then the whole batch is considered positive. Subsequently, you buy Kings Truffles trees under the understanding that there is a very small risk that some of your trees may not be quite to standard, even though they will be infected. On the flip side, there will be many trees that surpass the standard.
For 10 years in a row, Kings Truffles has been successfully infecting and selling truffle tree seedlings (previously under the name of Southern Cross Truffles). Many of these seedlings have then produced truffles four years after planting, given appropriate husbandries.
The initial tuber melanosporum seed stock was purchased in France and then imported into NZ. Under New Zealand bio security regulations each truffle had to be inspected and then DNA tested. All of these truffles were confirmed as being tuber melanosporum before they were released for our use. This stock was used until we started harvesting truffles from our own trees, which were infected by this imported stock. We now use all our own harvested truffles for infecting trees. Prior to using them each one is inspected and verified visually as tuber melanosporum. We also do a microscopic inspection to assess the mature spore density. We only use those truffles which have a high spore count. Those with a low spore count are spread around our trees.
Because we have a closed system whereby all of our infected trees have come from our imported and tested truffles or trees infected by these, we are confident that we have no contamination of tuber brumale (which is often mistaken as tuber melanosporum). On top of this, we also carefully inspect each truffle we harvest and then use in our nursery.
Proof of our confidence in this whole process is that we have planted 2500 of our own trees in 2014 and have planted another 2000 over 2017/18. In other words, we are putting our own money where our mouth is.
Not withstanding the above, we are quite prepared if you wish to get an independent expert to test the trees, but it would be on the condition that we would engage the expert ourselves and you would bear all the testing costs.