Friday 31 August 2012

The Gurnard's Head, Zennor


 

Among the more elaborate theories of the Hungarian psychoanalyst Sandor Ferenczi, is the idea of Thalassal Trend, the desire to return to a sea-state, manifested through dreams of becoming a fish. I invariably forget my dreams, but as a Pisces I’m jealous of anybody who nightly shoals and spawns with a thousand like-minded neurotics while I snore and dribble my way into the void.

If Ferenczi was still with us, I am sure he could convince me in a completely plausible way that I, too, harbour a fantasy of returning to a sea-state. Who knows, he might even get me into the water. As a child the best journeys always ended in the sea, where now they finish at the beach or, better still, a cliff. I want the scent of tide; the percussive smash and clawing of waves; the luminosity - but I also want to be dry. Dry and warm. Nowadays, the sea must seduce me from a distance.

A love of the ocean is an affair of the heart and mind, and nowhere is this desire better fulfilled than at the Gurnard’s Head Hotel. The Cornish roads whittle down to single tracks the moment you cross the county-line, and past St Ives, these meandering lanes, like Swinburne’s weariest river, eventually “wind somewhere safe to sea”.  A mile west of Zennor and you come to the Hotel, and beyond that, to the north, the Gurnard’s Head proper, an obstinate lava promontory, humped leviathan-like within the swell.

Painted across the Hotel’s roof in big letters is THE GURNARD’S HEAD; - a sign would blow over, or be ripped away by gales. The weather forecast for Zennor is The Shipping Forecast. Few trees grow here, and there’s a year-round khaki scorch to the grass. The first time I stayed it hailed on me in the car park, but when I visited this June the platinum sun rolled uninterrupted through the blue space of day.

Head Chef, Bruce Rennie, trained with Martin Wishart in Edinburgh, but his food is altogether more primal. There is no rendering of the familiar into novel, unrecognisable forms; instead, Bruce has perfected the more important skills of seasoning and cooking à point. Calves liver and lamb shank were nourishing and full of flavour, and if I hadn’t been worried about appearing greedy I would have immediately re-ordered Dover Sole served with capers and fennel.

The wine list is an affirmation of proprietor Charles Inkin’s taste. The worst wine lists are those that lamely offer you the world in the hope that you will see something you’ll recognise; the best scream “This is what we like, and you will like it too!”  I had my first taste of Fichet’s brilliant Hautes-Côtes de Beaune at the Gurnard’s, and was blind tasted on an interesting Slovenian wine that I couldn’t remember the name of the next morning.  The red wines are also strung together by Charles’ passion, rather than by region or country. Burgundy and Bordeaux seem to become deeper, darker versions of themselves when served on these Cornish cliff tops, and the Ridge Monte Bello I opened one night  appeared to add extra muscle mass to its already well-developed form.

In a few weeks I will get down to the Gurnard’s Head again, just in time for the equinoctial gales. If Cornwall is a kingdom, then Zennor is a fiefdom within it. I haven’t been anywhere else that makes this Island feel so much like an island. I will arrive for lunch, but lowering skies or a change in the tide has a habit of turning lunch into dinner there. I shall, as the Gurnard's Head brochure advises, “Eat, drink, sleep”, and maybe, just this once, dream briny, monocular, fishy thoughts.  

Tuesday 28 August 2012

Late August - but looks like mid-summer


An illusion of bounty as veraison begins at Tixover in 2012. This is Acolon which this year has put up a spirited fight against the weather. The soil is argilo-calcaireous-clay/limestone-but the mix sticks to gravelly French proportions.

The removal of the leaves adjacent to the 2nd cluster and the node immediately above creates a window for the slanting rays of the sun. We pull leaves at fruit set, when intrabunch shading is minimal. Shoots are topped at 15 nodes, so the removal of these two primaries should be compensated for by the remaining leaves and the growth of laterals.

Monday 27 August 2012

Vine Density


It can get pretty crowded in the vineyards of France. Within Champagne and Burgundy vine densities of around 10000 plants per hectare are normal, but more congested planting is not exceptional.   Head south, towards the Midi, and viticulture becomes more spacious: fewer vines, less leaves and shoots, and much more visible earth.  When I first consulted someone about planting densities for Tixover, the advice was “a tractor width plus a metre x 1.5 metre”; which worked out to 2000 plants per hectare for a 70hp machine. From somebody that had been in the UK business for a considerable time, this was sound practical advice; Nature is hard to dominate without mechanical assistance, and bare soil favours a rapid return to the full diversity of the indigenous flora rather than the unchallenged success of an invasive monoculture. Still, hoeing is hoeing, and the move from man to horses and tractors as the means of weed suppression, if anything, lowered vine densities within Burgundy and Champagne. For the monks of the Abbaye, the hoe must have been an instrument of self-flagellation.

There is an economic argument for high vine densities: more vines = more fruit, and a better return per hectare. In 2004, Champagne produced 140hl/ha. A small and early harvest in 2003 led to a proliferation in bud numbers and vine reserves, and this potential was fully realised in the near perfect flowering conditions of 2004. The subsequent harvest yielded both quality and quantity.

Another perspective on vine density is offered by Alain Carbonneau of Bordeaux University. In cool climates – Northern France, UK, Germany – Carbonneau suggests that shoot length needs to be a minimum of 80% of row width, in order that the vines are put under conditions that favour the induction of hydric stress. Carbonneau’s thesis is that the water capacity of a vineyard soil is depleted more rapidly if the total exposed leaf area of the overlying vineyard is maximised. This prescription works itself out into some interesting ratios. Burgundy’s 1m x 1m planting with a 20cm fruiting wire and shoot topping at 80cm perfectly satisfies Carbonneau’s conditions; whilst a row width of 1.6m demands a shoot length of 1.3m. Worryingly, the recommended tractor-friendly row dimension of 3m would require unworkable 2.4m long shoots to achieve similarly advantageous proportions.

What is common to Bordeaux, Burgundy and Champagne is that the peak in seasonal water deficits coincides with veraison. At some point between late July and early August, the vines divert their resources away from vegetative growth and towards fruit ripening. On the Cote de Nuits, crop evapotranspiration for the 4 week period that has veraison at its centre averages 130mm, with precipitation only replacing 60mm of this loss. Assuming that the vines' access to soil moisture is limited (arguably the defining characteristic of Burgundy’s finest appellations) then vine and berry growth will be constrained, and ripening accelerated. Just how these benefits are conferred on the bunches is still open for discussion. Richard Smart sees the advantages of water deficits deriving indirectly from reduced vigour and the concomitant improvement of the light environment in and around the clusters; whilst Mark Matthews and Stefano Poni posit a more direct link between advantageous gene expression and soil drying. Neither view precludes the other, but which side of the argument you favour has consequences as to how you spend your time in the vineyard. Those who follow Smart believe leaf removal, green pruning and vine architecture can substitute for terroir, whereas subscribers to the Matthews' dictum, “It’s the journey and not the destination that matters” will spend their time seeking out pedological conditions that optimise vine stress.

It may well be that in the UK's relatively damp, cool and sunless climate we have to embrace both strategies, and view the theories and prescriptions of Smart and Matthews as being in some sense simultaneous, rather than conflicting. On average, Burgundy picks Pinot Noir at 940GDD after budburst, and Champagne 870GDD. Nowadays, these summations are achieved in mid-September, but under the UKs maritime climatic regime these values are reached (if at all) in October, under lowering skies, downward spiralling temperatures and the constant threat of rain.  The skewed pattern in phenology between France’s northern appellations and the vineyards of Southern England is entrenched by flowering. Mid-floraison in Champagne and Burgundy occurs 2-3 weeks ahead of the most precocious English vineyards, which pushes veraison on this side of the Channel into late August and early September, when crop evapotranspiration and precipitation are often equivalent, and thus, free of hydric stress.

One anxiety voiced against close planting is that it increases the shading of one canopy by another. Logically, more distant rows will intercept more of the early morning and late evening sun than rows of the same height planted closer together. The idea has appeal, but as the illustration below shows (Courtesy of Cornell University) the gains from planting wider are marginal, and almost certainly counterproductive, as vigour and canopy shading will tend to increase at lower vine densities.  

 


 

The other multiple used to calculate vine density is within row spacing. As was the case with row width, the higher vineyards push into the eaves of the l’Hexagone, the tighter the spacing between the vines becomes. At Tixover, our widest spacing is 1.2 metres, and our narrowest 0.6 metres. The wider spacing reflects the advice we were given when we first planted the site, but we have since discovered that our vines are only comfortable pushing 5-6 shoots of even vigour.  To avoid shoot congestion and acrotony along the fruiting canes we decided to spur prune the vines. 

The above choices have given us two vine densities: the 0.6mx1.7m= 9700 vines per/ha; and the 1.2mx1.7m= 4800 vines per/ha. All vines have 1.3m, 15 node shoots, which gets us close to the ratio of shoot length to row width suggested by Carbonneau. The canopy density has been excellent in both vineyards, though we do remove two leaves on every shoot at fruit set - those immediately adjacent to and above the second cluster – to improve light exposure during the pre-veraison period when intra-bunch shading is minimal.

As with any field-based trial, the confounding variable is often the weather. Somewhere between May and July of this year, we lost nearly a month’s worth of an already short growing season, and I am doubtful that the crop will ever reach maturity. Interestingly, vigour this year has shown no increase despite the rainfall, and berry size at lag-phase is small. This can be interpreted in several ways, but I suspect root growth was suppressed by soil saturation through the spring, and the subsequent dry and warm weather we have experienced since fruit set has inducted some stress into the vines. Unfortunately, the two AG moisture probes we have in the ground have also become victims of the weather, so we will have to wait until next year to get good data on fluctuations in soil moisture availability and capacity.

Friday 17 August 2012

Angleterroir?


 
Superficially, our soil looks like some of the better bits of the Côte de Nuits. The soil is composed of clay (25%), limestone gravel (25%), silt (30%), and sand (20%). In the shallower parts of Grand Cru Romanée St Vivant you hit Bajocian bedrock at a depth of 30cm, and it’s the same for Tixover. Shuffling around on your haunches you might imagine yourself to be in Vosne. The first time I tested our soil, I also submitted samples gathered from across the Côte de Nuits. The results for Romanée-Conti confirmed it as “a good agricultural soil”, with macronutrients falling within the 2-3 range of standard farming indices; endorsing its potential as a wheat field should the wine business ever go to pot. The ratio of K:Mg in Le Chambertin and Clos de la Roche was skewed towards potassium, and the pH for all three sites was between 7.8 and 8.3. The results for the Tixover sample closely resembled those of the Grands Crus. All four had excessive calcium levels.

The second soil test was analysed in France. It introduced me to new concepts like cation exchange capacity (CEC), and base-saturation. Our soil was high in nitrogen and calcium, but weak in iron and magnesium. The ratio between calcium and magnesium influences soil structure, and soils that are base-saturated with calcium tend to be more porous than soils dominated by magnesium. A high Ca/Mg ratio generally facilitates water movements within the soil - up, down and sideways.

The most recent test, conducted by Albrecht Agriculture, was also the most thorough, and the results showed worrying discrepancies from the previous two analyses. Iron was recorded at a critically low level, and the CEC was measured at 30meq, which is high for a soil that is only 25% clay. The “clay and colloidal matter” bound calcium and magnesium ions in the ratio of 40:1. Our soil, Albrecht warned us, was like a sieve. We needed to add magnesium, lots of magnesium. But at least we were in good company: the three Grands Crus soils were similarly biased in favour of calcium base-saturation.

Confusingly, iron levels were only measured at 1ppm by the Albrecht people, but at 15ppm by the lab in Montpellier. We haven’t seen signs of chlorosis in the vines, so experience suggests the French analysis is the more accurate of the two. Moreover, despite identifying the chronically deficient iron levels, the Albrecht analysis didn’t propose any amendments other than the magnesium. Critics of scientific methodology warn about theory laden data, and the Albrecht obsession with the calcium:magnesium ratio may explain why in this instance they missed the low iron count.

CEC is a measure of the nutrient holding capacity of the soil, and relates principally to the number of internal and external bonding sites within the sample’s clay and colloidal fraction. The meq measurement was elevated in our sample by the mix of clays. Smectite, a volcanic mineral, was incorporated into our clay as it sedimented out, and its inclusion has significantly changed the soils properties. For Agronomist, Claude Bourguignon, smectite/montmorillonite clays, with their large internal surface areas, are particularly advantageous for red wine production. Just why these clays are so interesting to M. Bourguignon is worth consideration.

According to Bourguignon, the soils of Petrus together with most of Vosne’s Grands Crus (Romanée-Conti may be the exception) are luxuriously endowed with smectite. By contrast, the illite-kalolinite clays of the white Grands Crus have much smaller surface areas, and therefore their capacity to hold and exchange nutrients is considerably lower. Montmorillonite clays are also distinguishable from other clays by the extent to which they expand when wetted. Modest water deficits are seen as advantageous in wine production as they accelerate ripening and generally improve the quality and quantity of extractable solids from the skins, so a clay that absorbs and holds onto copious amounts of water would seem anomalous to the requirements of premium grape production. Montmorillonite clays do have a trick, however. Strong root growth and function require a good level of root oxygenation. The expansion of montmorillonite clays can be so dramatic that root growth and function become impaired. Moreover, the permeability of the clays can decrease due to sealing at their surfaces after wetting. Thus soils may look wet, puddled even, but this moisture is not necessarily available to the roots; a case of water, water everywhere and not a drop to drink. And just as they expand when wetted, so montmorillonite clays shrink when dried. A sustained period of drought will open up capillaries within the soil which then become exploited by the vines’ constantly regenerating mesh of short-lived rootlets. Taking into account the close connection between vacillations in clay particle size and Bordeaux’s changeable seasons, it is possible to model a shallow, smectite-rich soil in which the availability of moisture to the vine roots is almost continually held at deficit levels;- a terroir very much like that of Petrus, in fact.

Beneath the thin clay loams of Vosne’s Grands Crus is limestone. The ability of vine roots to populate hard rock is limited, but this fact hasn’t stopped commentators from positing this hidden union as the very foundation of terroir. However, a more probable explanation of limestone’s advantage to viticulture is revealed by a consideration of its physical properties. Limestone can hold large volumes of water, but, as was discussed in the context of clays, we must be careful not to confuse capacity with availability.  Movement of water through soils is multidirectional, and limestone can irrigate the clays resting upon it through capillary action. The extent to which the capillaries are opened will in turn depend upon the relative expansion of the clays and the degree to which calcium base-saturation has flocculated these, the most minuscule of soil particles, into larger agglomerations. In other words, the limestone’s ability to function as an aquifer is itself dependent upon the structure of the overlying soil. As was the case with Petrus above, we can imagine a possible balance between local effects whose equilibrium point sustains the vines at a slight and ultimately advantageous level of water deficit.      

On the Côte de Nuits the mercurial temperament of Pinot Noir brings colour and texture to the bland realms of geology and pedology. In her excellent articles on “Calcium in Viticulture”, Valerie Saxton talks of “terroir ridden France”, and Burgundy can seem like yet another scion of the Republic’s obsession with taxonomy and hierarchy. So completely pixelated has the map of Cote d’Or’s vineyards become, that it’s now virtually impossible for outsiders to see the whole picture. Twenty years ago, many New World growers censured the Côte d’Or. It just didn’t make sense: Grands Crus a stone’s throw from modest village vineyards; and Clos Vougeot, the oversized Circus Maximus at the centre of this antiquated world, just seemed to lump together everything that the rest of the classification had painstakingly tried to keep apart.

There are historical precedents for Burgundy’s sub-divisions, but the acute sensitivity of Pinot Noir coupled to the equally acute sensibilities of those that tend to it is the more remarkable story of this segregation. One way of classifying grape varieties is through their differing responses to water deficits. Anisohydric vines are said to be drought tolerant, whilst isohydric varieties are drought avoiding. The divide is not clear-cut, and relates to the strength of response different varieties show towards hormonal signalling (abscisic acid) from the drying roots. The stomata of isohydric varieties progressively close, rationing water uptake and loss, whilst anisohydric varieties maintain stomatal turgor, such that gas exchange, water uptake and carbon gain are unimpeded. Isohydric vines are “pessimistic” and anisohydric vines “optimistic”, inasmuch as the latter carry on as if they expect it to rain again tomorrow.

Some varieties seem capable of both responses, but in extremis, Pinot Noir is anisohydric, and Grenache Noir isohydric.  Lavish water use, as exemplified by Pinot Noir, brings with it a vulnerability to sustained drought. Pinot Noir, by rapidly depleting soil moisture can accelerate itself towards conditions under which its own metabolic processes become compromised, just like the man who saws-furiously at the branch he’s resting on. Without the self-buffering responses of isohydric varieties, Pinot Noir’s own water status is so immediately bound to the vicissitudes of soil moisture that it takes, in unirrigated Burgundy, a very special mix of extraneous pedological factors to consistently produce high quality grapes, i.e. those that are the result of sustained, but not impairing water deficits. Vosne’s Grands Crus are, indeed, exceptional.

Claude Bourguignon caused me to depart from thoughts of my own soil analyses and on-going struggle to get consistent data.  There have been reasons for optimism in most of the results, and I don’t doubt the fact that if Tixover’s three blocks of brashy soil were panelled into Morey or Chambolle you wouldn’t see the joins, but it’s ridiculous to start talking about terroir, particularly when we seem to have spent the last few years acquainting ourselves with a whole load of Nature’s disadvantages. I remember with incredulity, a vineyard owner in Long Island exploiting the argument that Bordeaux’s Crus were the finest in the World, and that Bordeaux’s vineyard were flat, and as his vineyards were flat, too, it followed that his wines were rivals to the Médoc.

As said, there was a time when the majority of New World growers rejected terroir, portraying it as either a perspicacious piece of marketing, or homey make-believe. But somewhere along the track these protagonists either gave-up on this line of attack or lost the argument, because producers in Chile, New Zealand and Mendoza nowadays reel-off neat invocations about the contingency of their own vineyard work that wouldn’t sound out of place in Vosne. Wine now seems so exclusively “made in the vineyard”, it’s hard to know if there is anything left for winemakers to do. In the New World, terroir has gone from being nowhere to being everywhere.

The ubiquity of terroir is problematic.   I take from the late Peter Sichel’s remark that only a fraction of Bordeaux’s vineyards genuinely exhibit terroir-characteristics, that terroir is a title bestowed like an honour or a peerage, rather than a democratic entitlement to which anyone with a vine growing up a wall has an equal claim. Accordingly, Richebourg and Petrus are the exemplars of terroir, the foundations and acmes of a system in which exceptionality and scarcity are paradigmatic.  In this context, the work of Claude Bourguignon, Gerard Seguin and Cornelius van Leeuwen is so pertinent because they are trying, in different ways, to cleave some scientific traction into our understanding of a much abused term. For those who crave more metaphysical accounts of grape quality, who will never be moved by terms like “vine water status” or “point quadrant analysis”, there is always Nicolas Joly. But this is to miss the point. When physicists revealed diamonds’ atomic structure they didn’t stop them from being a girl’s best friend.

I do share Peter Sichel’s instinct for parsimony, not least because the over-extension of any term, terroir included, eventually runs the risk of draining all significance from it. The meaning of words changes over time, and despite van Leeuwen’s attempts to give terroir intellectual rigour, I feel sure that the term’s appropriators will win out. “Sense of place” will read like a postcode.

More optimistically, the weakening of terroir is not going to stop some very clever people from giving us ever more concise formulations of past viticultural accomplishments, those for whom “sense of place” and “terroir” prompt the question: “And how did we get here?” As for the appropriators, I suspect every nascent English sparkling wine venture will claim its unique terroir, as will every newly planted desert of irrigated Sauvignon. Bertrand Russell once observed, “The method of postulating what we want has many advantages; they are the same as the advantages of theft over honest toil.”