When I say a young truffle tree, I really mean the Quercus Ilex inoculated with the Perigord Truffle at 1-4 years.
When we travel around the Perigord region, we always have our eyes open to surrounding truffieres. There are many to chose from. And they all have their differences. Second only to the species of tree, pruning methods have the biggest visual impact on a truffiere. Below is a photograph of a small section of our valley. The first thing to note is the number of truffiere in this region - there are a further two in this photograph that I have not highlighted, I wonder if you can spot them?
While the aesthetics of the truffiere is important to us, the driving force behind the truffiere is of course, the truffles. Good pruning methods and general care practices will impact significantly on the truffle yeilds.
Notoriously fussy fungi, the tuber melanosporum has only been farmed since the 1800s. Before this time, they were hunted (as the alba truffle still is) in the wild. So we take a very gentle approach in our truffiere. We tread carefully around the orchids, interfering as little as possible with a small nip here and there.
There are truffieres around us that are more 'wild'. They are planted in a haphazard way and are typically dominated by the common oak. They are beautiful in their way and they strike back to traditions held here generations ago, before the wars that saw an end to many of the local truffieres. They are more difficult to spot, the only giveaway being the cloths the truffle hunters tie in the branches to mark cracked soil in the late summer to signify something large, knobbly and black growing in the soil beneath.
The most common sight around here are the truffieres of holm oaks that are planted in rows that have not had the tops pruned. The trees can become quite large. While an ancient, unpruned holm oak can be something to behold, these truffieres, for me do not hold much beauty; the canopy above can close leaving a shadowy no place below them.
This particular truffiere is reported to still be producing truffles, although nowhere close to the number produced by trees in the adjacent field who are maintained in the same manner, but are still young and therefore not enormous. The best thing about this style of truffiere is that there is often wild life here. It is the place in the valley that I pass regularly and see the most action. Many deer, boar (not a truffle growers best friend), squirrels (black ones) and just today I saw two huge hares hanging out. In a world of ever expanding monocrop farming, this is a benefit that should not be sniffed at.
The modern truffieres tend to have a more manicured look. They are holm oaks with a smattering of other varieties, planted in neat rows. They have the tops pruned out and form balls not dissimilar from a regal topiary garden. From a distance, it is as though the field is strewn with green pom poms lazing in the French sun. This is what we are aiming to create. It is an example of humans working with nature to create something beautiful and deliciously productive.
Pruning the trees regularly encourages the light and water to penetrate the soil below. The truffles love this. They want to be bathed in sun all summer long. And when the rains come, they want to fully benefit from the deluge, allowing them to swell and engorge. This shape allows the low sun to hit the soil around the base of the tree throughout the year. The wide top on the tree also means that the midday summer sun with its simmering intensity will cast a shadow, preventing the base of the tree overheating and damaging the roots and developing truffles.
Keeping the trees healthy and well maintained will in turn keep the roots healthy. Vigorous roots support truffle activity. So by nurturing the tree, we are in turn supporting and encouraging truffle growth.
As we head out in to the field in late winter/early spring, armed with clean, sharp secateurs, we always keep in our minds the image of the truffiere are are aiming for. Our purpose remains clear so that we are not distracted.
Each tree in turn receives the same attention. We remove the protective casing and ensure that around the base of the tree is weed free. Take a moment to evaluate the tree. What is happening with it? Follow the leader stem with your eyes. Assuming the tree looks healthy, there are two key things to look out for:
The heights of the leader. We want our trees to be pruned small, so we encourage the plant to branch into a bush shape at around 1m. We cut off any growth above this point to stimulate side shoots and later bushy growth.
Has the leader stem split. Holm oaks like to split into many leaders, and they like to do this low down to the ground. We have seen this on many older trees and it does not appear to have an adverse effect. However, there are arguments that the plant can be more susceptible to wind damage. So, any secondary leaders are pruned off completely in favour of one solid, strong trunk.
Once these two factors are considered, you must remember the the 1/3 rule. Do not prune more than 1/3 of your tree or you are in danger of weakening it. As soon as you reach this amount. Stop. You can remove more next year. If, however, you have not yet reached your 1/3 allocation, you can now check to see how the plant is at ground level. Are there other shoots coming from the soil? If so, they can go. Finally, you can begin to remove any growth from the trunk. Starting from the bottom, you will slowly work your way up over the coming years to leave a smooth trunk.
Once finished, the protective cover is replaced over the plant. And slowly, we watch the farm grow.