Just landed back from the States. I really had a great time at the NATGA annual conference and I would like from this Blog to thank the organizers to bring me there. I got amazed how many of you followed these posts. So thanks again!
I had the chance to travel in both coasts and to visit 8 farms, and again like in most of my truffle trips overseas I notice that Quercus robur is one of the most used host trees for black truffle and I still wonder why. We have never used it in any of our truffle tree nurseries in any country, at least for black truffle. This oak grows pretty fast, too fast! and probably this is one of the main reasons why it gets contaminated so easily with other ectomycorrhizal fungi. Besides it, unless you are in a really hot area and you may need a closed canopy, to prune this oak and keep it “controlled” is a hard task. Moreover I have seen it in quite high tree densities, so even harder to keep enough sunlight for black truffle.
North Carolina is 2 degrees celsius over the higher natural temperatures where Tuber melanosporum grows naturally, this is 23,5ºC in the warmest month , so black truffle may enjoy a little more shade over there than usual. Brûles, as they´ll develop to the south looking for sun or north of the tree trunk looking for shade, will probably indicate us what truffle do prefer…
You may know there are several varieties or cultivars of Quercus robur, maybe the best that fits for a black truffle orchard due to its natural shape could be the one on the right of the top picture: Quercus robur ‘Fastigiata’ or “Cypress Oak”, on the left of the pic a”normal” robur shape.
Nevertheless, english oak could be a great host tree for the burgundy truffle, as we search for a close canopy asap, combined with other trees like beeches.
One of the main problems I saw on North Carolina and Virginia were soils with high tendency to compact in areas with too much rain in summer months. To rip and improve drainage is a must in some of them to avoid rotten truffles.
I enjoy propane burning to control weeds, if you are careful enough to avoid burning the irrigation pipes 🙂
a big hug!
Marcos S. Morcillo