Wednesday, July 27, 2016

Book Review: Suzanne Hoffman's Labor of Love

I write this review of Suzanne Hoffman's Labor of Love from a unique perspective. You see, I know and love the author of this book. I know the story of the birthing pains of this book. I was a member of a small Facebook group that the author formed to share the daily highs and lows of the book's progress. We laughed with her. We cried with her. We died with her. And then we basked in the reflected glow of her accomplishment when the initial copy rolled off the press. I travelled to Piemonte, along with my wife, and members of Suzanne's family and friends, to stand with her at the official book launch. It was while I was in Piemonte that I truly understood why this book and why this author for this book.

While a lot of attention, as regards Piemontese winemaking, has revolved around the battle of the modernists versus traditionalists, or the Burgundization of Barolo, the region has also been undergoing an under-reported transformation: the rise of women into the wineries' leadership ranks. And it is this under-explored story that Suzanne Hoffmann captures, and tells effectively and empathetically, in her initial publication Labor of Love: Wine Family Women of Piemonte.

EnotecaMarcella attributed the historically patriarchal leadership profile of the Piemontese wine industry to the following:
Out in the hills of the Langa, Asti, and nearby regions, society is rooted in tradition. There are a lot of good reasons for this as these areas were fairly poor farming communities until just the last 30 - 40 years. The family unit was and is still valued and respected above most all else. Piemonte has a tumultuous political history as well and the family unit had to be maintained to develop a sense of identity when the outside world was in flux.
Suzanne, in her introductory chapter of the book, builds on the foregoing and shows its implication on the Piemontese landscape: "Though women were the glue that held so many families together through war, poverty, and political upheavals, there had existed a societal prohibition against their inheriting land and working it as wine producers."

But, according to Suzanne, as she became more familiar with the region (and its people), she noted that a seismic change in this system was underway, led 9in the 1980s) by a number of "strong, courageous women ... who took the helm of their wineries." And this trend will most likely be further solidified by the fact that a number of young women began studying winemaking at the Enological School in Alba in the 1990s and are working alongside their fathers and grandfathers today, poised to take over ownership reins when/if the occasions presents themselves.

It is these stories that Suzanne explores in the Labor of Love. A total of 22 wine families (shown in the chart below) with women in leadership positions are profiled therein. But this is not a cookie-cutter book.

The book begins with an introductory chapter which relays the story of Suzanne's introduction to the region and a fortuitous meeting with Jeffrey Chilcott, the Marchesi de Gresy Cellar Master (I have had difficulty finding that estate in the middle of the day) which opened the door to this entire venture. Beyond that introductory chapter, each estate is treated in a separate chapter.

Each chapter begins with a genealogical chart but that is where the similarity ends as the stories are all so different. If we examine the first five stories that bear on the subject at hand, four of the estates are currently women-owned while the fifth features a woman who works alongside her father in the cellar while her sister works in Germany distributing the estate's wines. Of the four owners, three own the estates outright while the fourth is owned by three sisters. Of the three that are solely owned, one was acquired through an inheritance, the second was an acquisition, while the third took ownership upon the sudden death of her husband.

There are a wealth of stories here and Suzanne captures the threads and weaves a rich tapestry which takes us behind the labels and into the inner workings of a female-led enterprise. We see the challenges they face, challenges which would be foreign to their male counterparts -- in some cases challenges created by their male counterparts --and the solutions that they bring to bear on the problem. We see young women working alongside their mothers and wrestling with the issue as to whether they should follow their parent into this industry. We see the conflicted mothers, staying above the fray as children wrestle with that decisionmaking process.

Suzanne has a deep passion for the region and its people. And it shows. In the events preceding the book launch I saw her easy familiarity with, and deep knowledge of, the family running the Il Centro Restaurant in Priocca. I saw the joy in that family's eyes when Suzanne formally presented them with a copy of the book and told them the inspirational role they played in the project.

I saw it in the attendees at the launch event. The venue was packed, with almost total representation of the families included in the book. I saw their pride in the fact that their stories had been recognized, documented, and was being told to the outside world. And with the reputation that the region has for being insular, it was a testament to Suzanne's earnestness, tenacity, and reassuring persona, that they entrusted her, an outsider, with the material to tell the stories.

This is a beautifully presented book. Stunning front and back covers, high quality paper, and a multitude of high-grade photographs, many of the latter provided by the wine families themselves. This is a book befitting the subject and the region. And your bookshelf.

©Wine -- Mise en abyme

Sunday, July 24, 2016

The uber-natural style of Az Agr Frank Cornelissen (Mt Etna, Sicily)

The foundation of the Frank Cornelissen style is non-intervention and this philosophy permeates every aspect of the estate's grape-growing and winemaking activities. The figure below attempts to capture the Cornelissen viticultural environment in a single place and, in the areas of fertilization and pest management, we see that philosophy clearly demonstrated.

Frank is so committed to letting nature take its course that he has sworn off the broadly accepted Mt Etna practices of monoculture and high planting density to interplant local fruit trees with vines in pursuit of a more complex ecosystem.

The core objective of Frank's viticultural regime is the production of grapes that lead to profound wines. The practices to promote this goal include: crop management through pruning; tailoring of bunches to concentrate sugar; handpicking of defective grapes; late harvests; and multiple passes through the vineyards to ensure harvesting of fully ripened grapes.

In the cellar, Frank does not add sulfur either to combat oxidation or to combat micro-organisms. Wines are fermented by indigenous yeasts in small, food-grade plastic tubs. To ensure vintage integrity, all yeasts resident in the cellar are killed prior to the start of wine production. Fermentation is conducted with yeasts brought in from the vineyards on the grapes.

Both white and red wines are fermented with skin contact. Red grapes are lightly pressed and then placed in large fiber glass containers, if destined for early bottling, or into epoxy-lined, underground amphoras for longer-aged wines.

Underground amphoras
After our discussion and tour of the cellar we tasted four of the Cornelissen wines beginning with the Munjebel bianco 2014. This white wine is made from 60% Grecanico Dorato and 40% Carricante. Unlike the majority of Etna producers, Frank does not see Carricante as the best grape for the region's white wines. He feel that it is too acidic. The grapes for this wine are grown on 40+-year-old vines grown in the Calderara soprano and Borriglione vineyards. A total of 4000 bottles of this wine is produced annually. This wine is amber in color, a result of fermentation on the skins. Florality, spice, and a savoriness on the nose. Savoriness flows through to the palate. A textured wine with great acidity and a long finish.

Our next wine tasted was the estate'e entry-level red wine, the Contadino 2014. This wine is made from 85% Nerello Mascalese with contributions from Nerello Cappuccio, Alicante Bouchet, Minella nero, Uva Francesca, and Minella bianco. This 24,000 bottle production is sourced from 50+ year vines grown in the Piccolo, Malpasso, Campo Re, Crasa, Piano Daine, and Porcaria vineyards. This wine is red-fruit dominant but has some blueberry notes. Rich and earthy. Structured.

The Munjebel rosso 2014 is a pure Nerello Mascalese from 60+ year vines grown on the Chiusa Spagnolo, Monte Colla, Porcaria, Barbabecchi, Rampante, Piano Daine, and Crasa vineyards. Red berry fruit and drying tannins. Rich and balanced.

The final wine tasted was the 2014 Munjebel Feudo di Mezzo, in this case an en primeur sample. Savory with a preponderance of black olives. Long, bitter finish.

©Wine -- Mise en abyme

Thursday, July 21, 2016

Conversations with Frank Cornelissen of Azienda Agricola Frank Cornelissen (Mt Etna, Sicily)

Very few names are as tightly linked to the emergent Etna quality wine market as is Frank Cornelissen's and it is a testament to Brandon's relationships in the region that his winery was the first scheduled visit on our Sicily tour.

Cornelissen casts a long shadow. According to Roberto Camuto (Palmento: A Sicilian Wine Odyssey):
Frank ... had come to Etna because he believed it was the one spot in the world where you could make a wine entirely free of all chemicals, additives and modernity both in the vineyards and in the winery. ... Among fellow winemakers ... Frank is generally respected as a perfectionist. Among hard core enthusiasts in northern Europe and Japan, Frank has developed a fan base for a miniscule production ...
Nesto and di Savino (The World of Sicilian Wine) described Frank as having helped ignite interest in Etna wine. "Since 2008, when he first visited Etna, he has tantalized both locals and wine cognoscienti with his boldly intuitive artisanal wines." And intuition is the key here as he had no formal training or background in winemaking prior to embarking on this venture. His prior relationship to the industry had been as a wine broker.

Prior to heading over to Frank, we paid a walk-in visit to Cantine Russo, a visit which both started and ended later than we had anticipated. Our appointment with Frank was at 11:00 at the winery in Solicchiata so Brandon drove like a bat out of hell between the two locations because Frank does not like people being late for their appointments. We pulled up on the nose and Frank was outside to see that we had done so. Brandon heaved a sigh of relief and then went to look for parking.

The driveway slopes rather steeply from street level to the winery entrance and Frank was down at the bottom conversing with an employee. At the conclusion of that conversation introductions were made and we headed over to the cellar entrance. On the inside of the entrance there was low-walled container semi-filled with some type of liquid and we were asked to douse the soles of our footwear into that liquid in order to "decontaminate " them. This was the very first time I had ever encountered this practice. This guy was definitely different.

Frank and Brandon
Looking around the cellar, I was greeted by unfamiliar sights. In your typical cellar you see stainless steel tanks, or cement tanks, or concrete eggs, or wooden vats. Not so here. Instead I experienced a number of mud-colored, plastic-looking containers (turned out to be fiberglass) and a jarring absence of the expected.

Frank walked over to a large map on one of the cellar walls and embarked on a disquisition of site and grape growing in the Etna region. According to Frank, Etna can be divided into four sides:
  • Western
    • This side has never been planted to vines (too cold)
  • Northern
    • This area gets more sun than the southern slopes
    • In this zone it is all about the vineyard
    • He sees it as the future Côte de Nuit with Nerello Mascalese and vineyard diversity as the vehicles
  • Southern
    • Variety is key here
  • Eastern
    • Variety is key here.

Etna growing zones
The northern zone stretches between the towns of Linguaglossa in the east to Randazzo in the west and it is from within this area that Frank sources the grapes for his wines. He farms between 18.5 and 24 ha, 10 ha of which is owned and the balanced leased. The vines are distributed between 12 red and 6 white vineyard sites in Linguaglossa and one red and one white vineyard site in Randazzo. The location of the vineyard sites are shown in the figure below.

Linguaglossa as the right-hand map; Randazzo as the left
 Frank is looking to buy a new property each year up until he gets to 30 ha. His goal currently is to purchase Chiusa Spagnola, a site in Linguglossa that he currently leases. The characteristics that he looks for in a site include exposure and quality/type of subsoil. He sees high-altitude vineyards as "precious" due to their greater access to light.

As it relates to farming practices, Frank is not a big fan of biodynamic farming. He sees it as beneficial if used as a cure rather than as a practice. For example, if a site is "dead," biodynamic farming could be used to regenerate the soil. That was the basis for Steiner's introduction of the method: an attempt to combat beaten-up soils in Europe. Intensive agriculture has not been practiced on Etna so the soils are in good shape. There is no need for biodynamic farming here.

Biodynamic farming as a concept is fine but biodynamic wine does not exist by principle, according to Frank. Steiner had eliminated alcohol from his diet because, he said, it takes away lucidity and reasoning. You can say wine made from biodynamically grown grapes but not biodynamic wine.

As opposed to biodynamic farming, Frank sees benefits to organic farming with homeopathic applications. Cornelissen is certified organic (Frank observed that organic certification had higher standards in the US than it did in Europe.).

As regards the future, if Etna producers have the will to clean up the mess (define and adhere to growing-region constraints), they will become like Barolo; if not, they will become like Brunello di Montalcino. Today there are similarities between Brunello and Etna. In his view, Etna will be the next Barolo.

There has been rapid change in the last 15 years (unusual for an agricultural area and for Italy) but the region is suffereing from a lack of artisanal producers. There is no shortage of investors but what is really needed is more medium-sized wineries with hands-on winemakers.

Etna has great potential, says Frank. He sees very few wine areas with similar diversity from vineyard to vineyard. Did someone say Burgundy?

I will cover Cornilissen winemaking and the tasting of his wines in a follow-up post.

©Wine -- Mise en abyme

Wednesday, July 20, 2016

Barone di Villagrande (Milo, Sicily): slaking Mt Etna wine thirsts since 1727

On our return to Mt Etna (after a number of estate visits in the broader East Sicily), I spent the night at the Barone di Villagrande Resort -- co-located with the winery -- to facilitate an early morning cellar visit and tasting.

Pin indicates approximate location of estate in

Due to a very late arrival, I had not seen the property layout. I was floored when I went outside the following morning. The Resort provided a perfect vantage point from which to view the beauty of the multi-level amphitheater that was the vineyard.

Brandon was waiting in the courtyard so we stepped into the dining room for breakfast; and were immediately greeted by the warm, welcoming smiles of the office staff, a scene which was repeated every time I came into contact with a different member of the staff.

Marco Nicolosi (the owner and winemaker) was not in town so the visit was led by his wife, Barbara Liuzzo. She was ably assisted in this effort by Sebastiano Nolasco (Assistant Winemaker) and Giuseppe Rapisarda. We began the visit in the cellar but my initial line of questioning dictated a shift back outside to contextualize the source of the grapes.

The Barone di Villagrande estate has been growing grapes and making wine at the same location in Milo since 1727. The estate farms 14 ha there for its red, white, and Rosato wines and a smaller vineyard on the Island of Salina for the production of its Ripasso Malvasia (2400 bottles).

Because of its elevation -- 700 m on average -- maturation periods are lengthy with a relatively late harvest. The lengthy maturation period increases the complexity of the fermented wine. The altitude also contributes to a 30-degree differential in day-night temperatures in the spring and summer, aiding aroma and acidity retention. The area is subject to significant rainfall with an average of 1500 mm/yr. A steady wind aids in drying out the crop post rainfall events.

In describing the soils upon which the Villagrande vines are planted, the staff mentioned that they were the beneficiary of the formation of the valle del bove. According to their understanding, and supported largely by at least one scholarly reference, the valle del bove was formed by the collapse of a dormant volcano. The collapse of the dormant volcano resulted in landslides which carried debris as far as the coat. The Villagrande location benefited from deposits of some of this complex soil as it worked its way towards the sea. The Villagrande soil is rich in iron and copper and has adequate amounts of potassium, phosphorous and magnesium. It is poor in nitrogen and calcium-free.

Varieties planted in Milo are the white indigenous grape Carricante as well as Nerello Mascalese, Nerello Capuccio, and Nerello Mantellato. The international varieties Merlot and Chardonnay are planted to support what Barbara calls family wines: Sciara (80% Merlot and 20% Nerello Mascalese) and Fiora (90% Carricante and 10% Chardonnay). The average vine age is 40 years with the vines trained, for the most part, Guyot, cordon-spurred, and the scion resting on 1103 Paulson rootstock.

The estate was certified biologic in 1989 and uses nature to combat vineyard pests and diseases. Strategically positioned bushes on the margins and at transition points in the vineyard provide a natural habitat for flora and fauna. Forests to the southeast and east provide protection from offshore winds. Trees from these forests are used as sources for chestnut barrels with the wood dried for 4 to 5 years at Villagrande before being sent off to Trapani in Marsala to be finished. Some sulfur is used from time to time to combat mildew.

Villagrande plants 3 ha of Malvasia delle Ripari on Salina Island for the production of a passito style wine from sun-dried grapes.

The cellar was built in 1858 to help realize a vision of dual production lines. Prior to its construction, everyone made a Rosato by blending red and white wines. Barone di Villagrande knew that it made a great white wine so decided to build this cellar to allow two production lines. The vats were built in place and the cellar built around it. The vats are made of chestnut and are either 22,000L, 18,000L, or 500L.

Vats built in the 1850s
Harvesting is done by hand and the appropriate date is set based on sugar:acid ratios (the estate seeks a 2:1 ratio). Selection is done in the field. The wines produced by the estate is shown in the table below.

Training System
Etna Bianco Superiore

Guyot, spurred cordon

50 hl/ha
Etna Rosso
Nerello Mascalese (80%), Nerello Mantellato/Nerello Cappuccio (20%)

On skins 6 - 10 days
12 mos barrel; 24 mos bottle
Etna Rosato

Nerello Mascalese 90%, Carricante 10%
On skins 12-18 hours

Merlot (80%), Nerello Mascalese (20%)
Guyot, spurred cordon

On skin 20 days
18 - 24 mos 
in barrel; 6 mos in bottle
Carricante (90%), Chardonnay (10%)

In wood
8 - 9 months in wood
Malvasia delle Lipari (95%), Corinto Nero (5%)
In sun on racks 8 - 10 days pre-fermentation

Bottled 18 months after harvest
Legno di Conzo
Etna Bianco Superiore DOC
In oak barrels
1 year in wood; 1 year in bottle

At the completion of our cellar tour, we repaired to the courtyard where a table had been set up -- overlooking the vineyard -- for us to taste through the wines. Each wine was paired with a suitable accompaniment.

Barbara Liuzzo preparing to lead us in a tasting
Idyllic setting for a tasting
Wine tasting accompaniments
Lineup of the wines tasted
The first wine tasted was the 2011 Malvasia. It was paired with an aged, honeyed sheep's milk cheese and a potato concoction with olive oil and Sicilian onions. The Malvasia had been sun-dried for 20 days in order to reduce the water content while retaining the natural sugar levels. It was a light golden color and had a slight matchstick nose. Dried herbs, dried figs, and sweet white fruit are recalled. The honey on the cheese complements, while its saltiness contrasts, the Malvasia.Twenty four hundred bottles of this wine are made annually.

The 2015 Etna Bianco Superiore was paired with green olives (grown on the property), olive oil, and bread. The wine exhibited white peach, white pear, white pear skin, and a vegetality. Savoriness and dried herbs also evident. On the palate, clean, lean, and austere with a slight green note. An average of 300,000 bottles of this wine are produced annually.

The Etna Rosato 2015 (3000 bottles) was paired with dried tomatoes plus a cold soup with a crunchy ham topping. Strawberries on the nose of the Rosato. Beautiful texture and taste. Strawberry richness. Lemony-lime acidity, a spiciness, and late-arriving, rear-deposited tannins. The acidity bursts on the palate. A mineral, clayey, chalky finish.

The Salina Bianco is made from a blend of Malvasia delle Lipari (40%), Ruxignola, Cattaratto, and Insolia. Aromatic with rosemary and green herbs evident. Thick and rich on the palate but dry. A grapefruit tanginess.

The Etna Bianco 2014 has sweet white fruits on the nose along with white fruit skins and golden apples. Layered. Citrus reigns on the palate. Good acidity. Juicy.

The 2012 Etna Rosso was unctuous with faded sweet strawberries, red plum, nutmeg, dried herbs, dried bark, and mahogany on the nose. Great weight on the palate along with strawberry, raspberry, and spice notes. Great acidity. Long, dried herb, spicy finish. The tannins and acidity tell of a long life to come.

Brandon, Barbara and Giuseppe
This was an extremely pleasurable morning. Barbara and her staff were unequalled. The estate has a story to tell and the wines are telling it. Oh, by the way, Brandon had a great time.

©Wine -- Mise en abyme

Wednesday, July 13, 2016

Landscapes and soils of the Mt Etna grape-growing region

"All Etna soil rests on, or directly derives from, lava that flowed and hardened for thousands of years, along with ejected pumice, lapilli, and windblown volcanic ash" (Nesto and di Savino). I explore the origins, composition and deployment of the region's soils in this post.

Historically, eruptive events at Mt Etna have been of the Strombolian style but occasional Hawaiian-style eruptions generate considerable lapilli fall on the flanks (The Strombolian and Hawaiian styles are described in the table below.). Large active volcanoes with the Etna eruptive style present some of the most complex soil-forming environments on earth (James, et al.).

Factors such as diversity in age and characteristics of volcanic materials, land surface morphology, local climate, vegetation, and land-use history all contribute to complex soil spatial patterns. In the profile dimension, complex soils result from intermittent tephra deposition, anthropogenic disturbance (in the case of Mt Etna, over 70% of the vineyards are terraced), erosion and subsequent deposition. According to James, et al., "soil profiles may reflect the amount and frequency of tephra deposition as much as 'normal' profile-forming soil processes operating on stable surfaces."

Landscape Formation
Volcanism in the Etna region began during the middle Pleistocene, at around 600 ka. The peak today stands at 3350 m elevation and the base is 40 km across. At elevations below 1100 m, lava varies in age from the 2014/2015 flow to the 500,000-year-old tholeitic basalts of a small area on the lower part of the southern flank (James, et al.). The terrain of historical (12th century to today) flows, as well as some pre-historic flows, is dominated by aa lava (basaltic lava with a rough surface, pahoehoe (basaltic lava with a smooth or billowy surface), and toothpaste (transition between aa and pahoehoe) morphology (James, et al.).

On Etna, depositive explosive activity from the summit crater is frequent with less frequent eruptions, often with higher effusive rates, from the flank vents and Strombolian activity from vents high on the volcano. The tephra varies in deposition rate and particle size with distance and direction from the source and accumulates unevenly on rugged lava surfaces. As an example, areas on the western and northwestern slopes of Mt Etna are barren rockscapes due to insufficient topsoil for significant vineyard development.

Soil Formation
As described above, volcanic activity of Mt Etna is both effusive (lava flows) and explosive (airborne ejection of pyroclastics). According to Nesto and di Savino, the lava flows create a patchwork of terroirs that is pertinent to any discussion of Etna contradas. Initial flows are barren rock pasteurized by heat which, after cooling, require hundreds of years to erode into soil and develop hummus, and, in so doing, become suitable for vines. The erosion product is sand rich in potassium and other minerals. Organic matter, created initially by the growth of micro-organisms (and later by plants and animals), results in rich, fertile soil.

But, according to Marco Perciabobco (Department of Agriculture, Sicily Region), soil parent material in the Etna environment is primarily pyroclastic (My prior post on volcanic soils detail the weathering of these materials). Weathering of this coarse-textured parent material, according to Marco, produces soils with an "aerated hypogeal (underground) environment and the following characteristics:
  • Extremely well suited for the growth and development of vine roots
  • Soil water stagnations are rare
  • They warm easily (this generates stable conditions for the occurrence of the chemical reactions required for the weathering of the finest materials.

Soil Distribution
According to Perciabobco, the Department of Agriculture's soil survey dataset shows five different landscape systems in Etna: northern; northwestern; eastern; southeastern; and southern. The soils of these environments differ in the degree of weathering of the primary clay minerals. From north to south wetness decreases and so does weathering of the volcanic constituents. The soils of the northern landscape, when compared to the soils of the south, are finer textured, have a higher organic matter content, and a have a higher value of cation-exchange capability.

Bill Nesto MW and Frances di Savino, The World of Sicilian Wine.
James, et al., Development and spatial distribution of soils on an active volcano: Mt Etna, Sicily.
Sonia Calvari and Harry Pinkerton, Lava Tube Morphology on Etna and evidence for lava flow emplacement mechanisms, J Volcanol Geotherm Res 90 (3-4) 1999.

©Wine -- Mise en abyme

Monday, July 11, 2016

Climate in the Mt. Etna grape-growing region

In a recent Mt. Etna wine masterclass held in London, Ian D'Agata pronounced that a combination of three factors contribute to the "special" nature of the region's wines: (i) an alpine climate in a Mediterranean land; (ii) volcanic soils: and (iii) the predominance of ungrafted, pre-phylloxera vines ( In this post I will explore the first of the mentioned factors.

At 3,350 m (10, 991 feet), Mt. Etna is the highest mountain in Sicily. Marco Perciabobco of the Department of Agriculture, Sicily Region, describes the region's climate as "mesotermic humid sub-tropical with dry summers." He sees it as a typical Mediterranean climate characterized by an average temperature (coldest month < 18℃, in warmest month > 22℃) and a rainy period mostly concentrated in the autumn and winter months. Rainfall in the region is distributed as follows: between 1.000 and 1.200 mm/yr on the northern, eastern, and southeastern slopes and 500 mm/yr on the southwest slopes.

According to Nesto and di Savino (The World of Sicilian Wine), at the highest elevations for viticulture, the climate is similar to North Italy's, becoming more Sicilian as you proceed downslope. As a result, growing environments differ depending on altitude and aspect.

Etna elevation map. Source:
The chart below shows the impact of altitude on the grape-growing environment. According to Nesto and di Savino, conditions at the highest elevations are particularly helpful for white and rosato wines and grapes used in their production can be found growing as high as 1300 m (4265 feet). These high-elevation climatic conditions also reduce the incidence of vine pests and diseases and naturally limits vine yield. Below 900 m, conditions become more suitable for red wine production.

As shown on the below chart, growing conditions are also significantly impacted by aspect.

Data from Nesto and di Savino

The Nebrodi Mountains offer some protection to the north slope of Mt Etna but some wind does make it over the top, bringing rain in the autumn and winter and moisture year-round. There are some benefits to this moisture though. The runoff, unlike the case for the runoff on the eastern and southeastern slopes, proceeds downhill at a moderate pace and is absorbed by the lava beneath the soil, This water store then becomes available to the vine roots during the growing season. The major beneficiary of this process is the area between the towns of Solicchiata and Randazzo. The wind from the northeast blows steam from the vents to the southeast creating a shadow which serves to reduce evaporation.

The southeast and eastern slopes are unprotected from the autumn and winter rains but the combination of rapid runoff and early morning sun contribute to their attractiveness as growing regions (especially for whites).

The west slopes are generally the worst for quality wine production because of the late arriving sun.

I will cover the Mt Etna soils in my next post.

©Wine -- Mise en abyme

Wednesday, July 6, 2016

Volcanic soils

During my recent visit to Sicily, I was able, thanks to the connectedness of my good friend Brandon Tokash, to spend three days in the Mt Etna region visiting producers and tasting a broad selection of wines. A key determinant of the character of those wines is the volcanic soil on which the vines are grown. I would, therefore, like to spend some time reviewing volcanic soils, in general, and Mt. Etna soils, specifically, prior to sharing my actual experiences in the region. I begin with the following mini review of volcanic soils.

According to V. E. Neall, volcanic soils cover only 1% of the earth's surface but supports approximately 10% of the world's population, the latter fact attributable to its high natural fertility. Volcanic soils are wholly derived from volcanic parent material and are distributed globally as shown in the map below.

Parent material escapes the volcano either as a result of lava flows or volcaniclastic events. According to Neall, only strong tropical weathering will reduce lavas to finer-grained volcanic soils and soils formed from this source are usually of low fertility. Further, of soils formed from lava, basaltic lavas (low viscosity, ability to flow large distances on low gradients) are the most significant source of parent material.

Soils from volcaniclastic parent material are, on the other hand, very productive. Volcaniclastics are usually classified as of pyroclastic (explosive) or epiclastic (erosional) origin. The figure directly below shows the origin and components of these two classes while the figure following shows the grain-size classification of volcanic fragments and rocks.

Formation of volcanic soils from parent material is effected through a combination of two processes: (i) the formation of non-crystalline materials (active Al and Fe compounds) and (ii) the accumulation of organic matter (Neall). This combination of processes is termed "andosolization" and its extent is affected by time, climate, the proportion of volcanic glass in the parent material, and grain size and vesicularity of the parent material (Neall; Ugolini and Dahlgren):
  • Andisols form rapidly in humid climates and alter to other soil orders as soil age and degree of weathering increases
  • Volcanic soils contain differing levels of volcanic glass
    • The lower-silica, higher mafic (high magnesium and iron) volcanics weather more rapidly than higher silica, lower mafic (high sodium and potassium) volcanics
  • A dense, high-silica, igneous volcanic rock will weather more slowly than a less dense and highly vesicular pumice (rocks containing holes made by gas escaping from cooling lava) of identical composition.
The first component of volcanic rocks to undergo weathering is volcanic glass and, as shown in the figure below, it weathers to a clay type called a short range order clay (SROC) which is characterized by a weak degree of crystallinity. The allophane and imogolite clays differ primarily in their shapes, with the allophane presenting as hollow spherules and the imogolite as a "tubular, thread-like material."

Selected characteristics of Andisols are presented in the figure below while the development of volcanic soils in varying climatic environments are presented in the figure following.

According to Neall, volcanic soils are usually the dominant soil in young volcanic landscapes. "Surrounding the volcano, and for large distances downwind, there may be a wide variety of landscapes upon which fine ash has accumulated over thousands of years by tephra accretion."On lowlands, that tephra could have accumulated to great thickness, providing deep, fertile volcanic soils. In hilly landscapes, erosional activity may have resulted in relatively thin soil profiles.

Shoji and Takahashi view the significance of volcanic ash soils thusly:
  • The periodic additions of volcanic ash generally improve the soil physical and chemical properties and renew the soil productivity
  • They accumulate a large amount of organic carbon and nitrogen as important components of soil organic matter that are the main source of nitrogen for plants and various nutrients and energy for soil organisms
  • The accumulation of carbon is important in the sequestration of atmospherreic carbon dioxode, one of the most important greenhouse gases
  • Soils with well-developed structure can hold a large amount of plant-available water.
Giovanni Ponchia, lead oenologist for the Soave Consorzio, identifies volcanic rocks as having a high level of macro-porosity in soils and "these pores allow the rocks to store water up to 100% of their weight and then release it very slowly thanks to their high water retention coefficient." This quality renders the rocks a very important source of water for vine root systems, "especially in years with little rainfall or even drought."

Fiorenzo C. Ugolini and Randy A. Dahlgren, Soil Development in Volcanic Ash.
Daniel Scheffer, Volcanic Soils produce unique wines, Style, South China Morning Post, March 2015.
McDaniel, P.A., Lowe, D.J., Arnalds, O., Ping, C.-L., 2012. Andisols. In: Huang, P.M., Li, Y,  Sumner, M.E. (editors) “Handbook of Soil Sciences. 2nd edition. Vol. 1: Properties and Processes”. CRC Press (Taylor & Francis), Boca Raton, FL, pp.33.29-33.48. 
Murcia et al., Volcaniclastic deposits: terminology and concepts for a classification in Spanish, Rev. Geol. Amér. Central n.48 San Pedro de Montes de Oca Jun. 2013.
Sadao Shoji and Tadashi Takahashi, Agricultural and Agricultural Significance of Volcanic Ash Soils
V. E. Neall,Volcanic Soils, Land Use, Land Cover, and Soil Sciences -- Vol III, Encyclopedia of Life Support Systems., Andisols.

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