THE GRAPE PHYLLOXERA PLAGUE AS A NATURAL EXPERIMENT: THE UPKEEP OF VINEYARDS IN CATALONIA (SPAIN), 1858–1935

Abstract

This paper analyses the impact in Catalonia of the grape Phylloxera plague in Europe (1865–90). A statistical model is used to analyse the economic resilience of 35 districts in Catalonia to this external ecological and economic shock, and to explain why districts in the provinces of Barcelona and Tarragona resumed growing wine grapes after the plague, in contrast to districts in Girona and Lleida provinces. The opportunity cost of labour, the demand pull of Barcelona's commercial growth, and the agro-climatic suitability of land for growing grapes are used to explain the differing capacities of districts to endure the Phylloxera plague in Catalonia.

INTRODUCTION

The grape Phylloxera plague was simultaneously an ecological external shock and a deep economic crisis in the European vine production, which led to a new start.² For vine growers, both the ecological and economic impacts were closely related to the globalisation experienced before the First World War. The insect that started killing the French vines in 1863 had arrived from America as one of the bioinvasions channelled through the ‘Columbian biological exchange’.³ By the end of the nineteenth century, the plague had ravaged every old European grapevine. The recovery of European wine production and exports was only possible through another ‘Columbian exchange’ in the form of American varieties of vines, which had coevolved with the Phylloxera insect for three centuries. These were grafted onto the rootstocks of old European ones in order to replant new vineyards resistant to the plague, which might retain the taste of traditional wine. This large-scale replant had to be undertaken in a newly integrated and highly competitive global agrarian market.

For an economic and environmental historian, the grape Phylloxera plague can be seen as a natural experiment that enables us to test the economic impacts and reactions of a sudden ecological shock by using a comparative approach.⁴Figure 1 shows the advance of the plague from the South of France in the 1860s to the rest of Europe in the 1890s, where it ravaged parts of the regions previously specialised in wine production. This created a succession of wine frenzies in different areas, where new vineyards were planted to substitute for French wines until the plague reached them. The rise and fall of the relative price of wine in terms of wheat shown in Figure 2 reveals a boom during the 1870s–80s and crash during the 1880s–1900s. This economic environment of high price volatility, a trend in rising unit costs, and an atmosphere of social unrest, were to mark out the viticulture path into the global agrarian crisis at the turn of the century.⁵

Figure 1. The spread of the grape Phylloxera plague in Europe, 1868–1920. Source: Adapted from Piqueras, Filoxera en España, p. 106.

Figure 2. Wine produced in France and Algeria and the wine price in Barcelona, 1870–1914. Notes: Wine production in million hectolitres, left-hand axis. Wine price in pesetas per hectolitre, right-hand axis. Source: Garrabou et al., Explaining agrarian specialization; Garrier, Philoxéra, p. 175.

Only some European regions growing wine grapes were able to survive the economic impacts of the Phylloxera plague. In order to recover from the ecological shock, they had to adapt wine production and exports to the price volatility and rising unit costs experienced during the first agrarian world crisis. Understanding why some of them succeeded while others failed may provide answers to the question how an economic activity can react to a sudden external ecological shock. We focus our analysis on Catalonia (Northeast Spain), contrasting the ability to endure and recover from the plague shown by the main grape growing districts in the provinces of Barcelona and Tarragona, against the failures experienced in the districts of Lleida and Girona.

CATALAN VITICULTURE BEFORE AND AFTER PHYLLOXERA

What happened in Catalonia during the plague and afterwards? Figure 3 shows that the four Catalan provinces responded in different ways to the wine frenzy between the 1860s and the mid-1880s, and the subsequent ruin of all vineyards. The provinces of Barcelona and Tarragona, where vineyard specialisation had taken root as early as the seventeenth century, did not experience a dramatic increase in new plantations when the French vines became ravaged. Land under grapevines rose only 16 and 15 per cent, respectively, from 1860 to 1885. After the death of the old vines, vine growers were able to replant nearly as many hectares of new vineyards as before the plague. By 1935, there were six per cent more hectares planted with vines in Barcelona than in 1860, and only one per cent less in Tarragona.

Figure 3. Land under vineyards in the four provinces of Catalonia, 1860–1935 (hectares). Note: 1880–84 data are only available for the provinces of Barcelona and Tarragona. Sources: Moreno Ramírez, Estadística Territorial; Martínez Quintanilla, Provincia de Gerona, pp. 295–97; Llovet Mont-Ros, Contribución; Roig Armengol, Memòria; García de los Salmones, Invasión Filoxérica, p. 193; Junta Consultiva Agronómica, Estadística, pp. 265–300; Garrabou and Pujol, Canvi agrari, pp. 80–1; GEHR, Estadísticas históricas; Heras and Mas, Viticultura i Filloxera; Piqueras, Filoxera en España, p. 135; Valls, Dinàmica.

Vineyards evolved differently in the other two provinces, which in 1860 accounted for less than one third of the Catalan acreage. The frontier province of Girona was the first to be hit by the plague coming from France in 1878, allowing almost no time for a sudden big boom before the grapevines started to die.⁶ Grape growers were only able to replant one-third of the acreage of vineyards that existed in 1860. The province of Lleida experienced the highest increase of new plantations that tried to substitute for the shortfall of French production and exports, nearly doubling the area planted with pre-Phylloxera vines before the plague destroyed them. Afterwards, growers were only able to replant with resistant varieties less than half the hectares of vineyards that existed in Lleida in 1860, as Figure 3 shows.

Thanks to technical improvements made by grape growers mainly in the province of Barcelona, through the increase in manuring and the use of chemical fertilisers, the hectolitres of grape juice produced increased even more than the acreage of new vineyards planted after the grape Phylloxera plague. Table 1 shows the mean yearly wine production was 33 per cent higher in 1930–34 than in 1890–94, while the hectares planted with grapevines had increased by 28 per cent. The recovery of vineyard specialisation from the Phylloxera plague went beyond a simple restoration of an earlier regime, especially in the province of Barcelona. From 1890 onwards, Catalan grape growers and wine industry succeeded in increasing wine production to supply the new emerging export market for Mediterranean agricultural goods in North Europe and North America.⁷

Table 1. Five year mean wine production in the four provinces in Catalonia, 1890–1934 (hectolitres of grape juice)

	Barcelona	Girona	Lleida	Tarragona	Catalonia
Note: Regular yearly statistics of agricultural production in every Spanish province only began in 1890. Source: Calculated from GEHR, Estadísticas históricas.
1890–94	10,330,557	321,856	8,499,954	8,623,763	27,776,129
1895–99	4,451,321	460,822	3,924,483	6,082,960	14,919,586
1900–04	9,407,277	811,231	3,127,252	6,574,141	19,919,901
1905–09	9,128,789	831,906	1,140,292	7,080,729	18,181,716
1910–14	12,150,214	850,807	1,373,239	8,175,214	22,549,474
1915–19	18,067,230	1,957,778	1,365,749	9,320,052	30,710,809
1920–24	21,474,627	2,268,922	1,712,615	12,122,787	37,578,951
1925–29	18,468,333	1,647,409	1,048,112	9,369,795	30,533,649
1930–34	13,773,209	1.207.384	1,120,856	7,768,326	23,869,775
Δ 1890–94 to 1930–34	3,442,652	885,529	−7,379,098	−855,437	−3,906,354
%Δ 1890–94 to 1930–34	33.3	275.1	−86.8	−9.9	−14.1
Δ 1890–94 to 1920–24	11,144,070	1,947,067	−6,787,339	3.499.025	9.802.823
%Δ 1890–94 to 1920–24	107.9	605.0	−79.9	40.6	35.3

However, Catalan vine growers in the provinces of Lleida and Girona were unable to endure the Phylloxera plague and restart grape growing. The vineyard acreage peaked in 1885, with 367,445 ha planted in Catalonia (58,961 more than in 1860, despite the 33,670 ha ravaged by the plague in Girona). From 1885 to 1935, nearly 90,000 ha were lost in the province of Lleida alone from the 109,317 ha previously planted with vines that had disappeared in Catalonia in the meantime. Why were so many vine growers throughout counties located in the provinces of Barcelona and Tarragona able to overcome the plague and keep most of their vineyards, while the majority of them in the provinces of Lleida and Girona failed and gave up this activity?

A simple comparative analysis reject the answer that entrepreneurial innovations developed as institutional responses to the general agrarian crisis at the end of the nineteenth century, such as the spread of cooperatives. Cooperatives had appeared in all four Catalan provinces. They organised commercial channels to sell outputs or buy new inputs for olive oil and cereal production, as well as grape growing.⁸ We can also discard an answer based on differences in natural endowments, although we consider that agro-ecological features did play a role that has to be taken into account in combination with other economic factors. For example, all the rural districts in the province of Girona, and also those in the eastern part of Barcelona province, had higher rainfall than the rest of Catalonia. This might have allowed them to overcome the agrarian crisis at the end of the nineteenth century with a wider range of agrological options, instead of having to resume grape growing.

Our hypothesis is that the answer lies in economic and socio-environmental history. We consider that the most apparent difference between the Barcelona and Tarragona provinces that survived the plague, and the Lleida and Girona provinces that did not, was the long history of vineyard specialisation. Grape growing had become a true culture in these specialised rural areas that was tightly rooted in agrarian societies and cultural landscapes.⁹ The factor endowment, know-how, and skills that had been accumulated in the provinces of Barcelona and Tarragona enhanced the economic resilience of vine growers, allowing them to persist after the plague.

Lleida and Girona provinces differed. Until the 1860s, Lleida not only had a lower acreage of grapevines, but the vines were often planted in sparse rows between strips of land alternatively sown with cereals or let fallow, surrounded by olive or almond trees growing on the margins. This traditional pattern of intercropping fitted well with an age-old agricultural feature of the Mediterranean landscapes. The small proportion of vines was part of an agrarian system devoted to growing the traditional Mediterranean trilogy: a little oil and wine for local consumption, with as much cereal as possible. In the provinces of Tarragona and Barcelona, however, something very different happened from the seventeenth century onwards: they specialised in wine, linked with increasing exports to the expanding Atlantic economy.

HOW A COMPARATIVE ADVANTAGE EMERGED

There is a consensus among economic historians that this commercial vineyard specialisation, developed in the littoral districts of Barcelona and Tarragona provinces, played a key role in the relatively early phase of industrialisation and modern economic growth in Catalonia. Since the publication of Pierre Vilar's La Catalogne dans l'Espagne moderne (1962), historians and economists have stressed the role played by the spread of vineyards from the seventeenth. Brandy and wine exports linked the Catalan economy to a large foreign market from which it could import cotton. The possibility of exports deepened regional specialisation and offered an increasing population a living, thus avoiding the Malthusian fate associated with fast population growth. It also increased the rural population's purchasing power and their consumption of industrial textiles, and enabled landowners or their inheritors to accumulate rural savings, which were increasingly invested in new trading or industrial enterprises and railways.¹⁰ This strong historical link between vines and the cotton industry in Catalonia is in sharp contrast to the trend of ‘vigne contre draperie’ (vines vs cloth), which characterised other contemporary regions, such as the Languedoc in France.¹¹

Many economic and environmental historians also regard commercial specialisation in woody crops such as vines, olive or almond trees as a key feature in the available capabilities for the agrarian development in the western Mediterranean basin during the eighteenth and nineteenth centuries, where agrarian specialisation became a characteristic vehicle for Smithian-type economic growth.¹² However, it has been stressed more recently that the Dutch-English mode of agrarian revolution in the European Atlantic area was impractical in the Mediterranean region due mainly to its low rainfall.¹³ Therefore, environmental constraints also played an important role in the vineyard specialisation developed in southern Europe during the last stage of pre-industrial ‘organic’ agriculture.

The concept of an ‘organic economy’ may help to highlight this relationship between the environmental constraints and the economic forces behind the viticultural focus of agrarian development in the western Mediterranean basin.¹⁴ From a historical standpoint, we consider ‘organic’ any agrarian system in which nearly all of the energy and material flows come, directly or indirectly, from the photosynthetic capture of solar radiation. In this area-based energy system, the entire economy is highly dependent on the biological net primary production that can be attained from the land.¹⁵ A key feature of this organic agriculture was the bioregional diversity of limiting factors that became bottlenecks for economic development. Consequently, technological and socioeconomic responses to these environmental constraints necessarily had to be different. The bioregional diversity of past organic agrarian developments stands in very sharp contrast to the uniform global tendencies that characterise the great transformation undertaken after the ‘green revolution’ of the twentieth century.

One of the main goals of our research project is to conduct a historical analysis of the links between energy efficiency, land-use efficiency, and healthy landscape ecology from the perspective of ecological economics.¹⁶ Specifically, we intend to assess and explain the role played by market specialisation in driving the diverse agrarian systems in the western Mediterranean basin towards a more advanced organic economy prior to the second industrial revolution and the start of the cheap oil era. Ecological economics often sees trade as a two-edged sword; while trade has often been a powerful factor in environmental degradation, it can also foster a better allocation of resources, which might be useful for reducing human impact on natural systems. The first outcome may arise, for example, by unlocking nutrient flows that were extracted by crops in exporting regions and excreted in wastes accumulated by consumer ones without any possible return to soils.¹⁷ The second outcome may actually arise through a backward shift of the limiting factors known in ecology or agronomy as ‘von Liebig's minimum’, either indirectly with a product specialisation for which each bioregion has a relative ecological optimum, or directly by transferring limiting goods from one bioregion to another.¹⁸ Economic and environmental historians can contribute to a clearer assessment of this complex and often ambiguous relationship between trade, economy, and ecology through the comparative analysis of different historical paths of commercial specialisation and globalisation.

We contribute to this research by analysing the scope of trade in Catalonia in the production and consumption of staple agrarian products during the second half of the nineteenth century. Having reconstructed the energy balances of the agrarian system prior to 1860 in a series of local case studies so as to compare them with current values, and having assessed the changes in land use and its impact on landscape ecology, we now aim to identify the turning points that transformed a specialised Catalan agricultural sector into a globalised one before and after the agrarian crisis at the turn of the twentieth century.¹⁹ The agrarian specialisation in brandies, wines, and sparkling cava in the Catalan provinces of Barcelona and Tarragona has three main features. First, it advanced slowly but steadily from the seventeenth century until the sudden Phylloxera boom and crash. Second, grape growing was not a monoculture but always combined with cereals and other crops in several types of complex agrarian landscapes. Third, vineyard specialisation never became a monoculture but coexisted with other crops. The percentage of cropland devoted to grape vines remained locally diverse and sometimes changed location throughout the history of grape growing.

Following many past Catalan historians, who comparative analysis based on case studies and descriptive statistics, we began by identifying the variables to build a model to explain agrarian vineyard specialisation in the province of Barcelona and Catalonia more generally in the mid-nineteenth century. We assembled available data on vineyard acreage in the 35 districts of the four Catalan provinces in 1858–60, 1885–89, and 1922, shown in Figure 4, and incorporated statistics on population densities, shown in Figure 5. Next, we compiled district level estimates of the heliothermal indices of Huglin and Winkler to assess the agro-climatic local suitability for growing grapes, together with the weighted average in the slope of lands.²⁰ The indices are shown in Figure 6 for Catalonia.

Figure 4. Percentage of cropland devoted to vineyards in the districts of Catalonia. Source: Calculated on the basis of data and sources referred to in Figure 3.

Figure 5. Population densities in the districts of Catalonia, 1860, 1887, 1920. Source: Own calculations based on data available at the Centre d'Estudis Demogràfics. [Accessed 27 May 2009.] Available from URL: http://www.ced.uab.es/index.php?newlang=eng

Figure 6. Agro-climatic aptitude for growing vines in Catalonia. Notes: Growing vines requires a Huglin index of at least 1,500 and a Winkler–Amerine index of at least 2,000. The Huglin index of helio-thermal aptitude is obtained by the expression: IH = Σ[(T_a – 10°) + (T_m – 10°)]K / 2, where T_a is the daily average temperature, T_m is the maximum daily temperature during the active period of vegetation, and K is the length ratio of days varying from 1.02 to 1.06 between 40 and 50 degrees of latitude. The Active Thermal Integral (ATI), is calculated by adding the daily mean temperatures above or equal to 10°C during the active period of vegetation between March and October: ATI = ΣT_a, where T_a is the active temperature. The Effective Thermal Integral (ETI) of Winkler and Amerine is the sum of effective daily mean temperatures, calculated from the monthly average temperatures multiplied by days of each month during the growing season from April to October: ETI = ΣT_e, where the effective temperature (T_e) is the active temperature (T_a) minus 10°C. Source: Own calculations, based on GIS data, by J. Marull, M. J. Cordobilla, and F. Rodrígez-Valle for the research project SEJ2006-15108-C02-01/GEOG. A Geographic Information System (GIS) spatial interpolation of a resolution of 180 m has been done based on the data of air temperature taken from 160 weather stations (one station per 200 km²) for the period 1961–90.

We started building and applying this econometric approach to explain the local differences in vineyard or cereal specialisation around 1860 in the nearly 300 municipalities of the province of Barcelona. In a first set of statistical tests, we used a model that combines the ‘Boserupian’ push of population increase (measured with the previous population growth from 1718 to 1860), the demand pull of a ‘Smithian-type’ of growth (measured using the terrestrial distances to the nearest seaport), and the agrological suitability of land for sowing grain or growing wine grapes (as measured by mean rainfall, slopes and frost risk).²¹ This historical model did not aim to explain all types of vineyard specialisation in all time periods and geographic locations, but the role played by this specific set of factors throughout the long-lasting spread of vines in the municipalities of the province of Barcelona that led to a particular organic agrarian economy during the second half of the nineteenth century.

POPULATION GROWTH AND AGRARIAN CHANGE

As Ester Boserup pointed out, the relationship between population growth and agricultural innovation is complex and changeable. While in some range the increase of population density becomes an important driving force for the development of more intensive land uses, such as the Mediterranean viticulture, beyond a certain threshold, further increases in population density become related to industrialisation and urbanisation that may limit the opportunities for specialisation in grape growing because they increase the opportunity cost of labour. There is also a lower threshold of population density, below which the ‘Boserupian’ population pressure does not lead to agricultural intensification and favours more labour-extensive land uses, such as cereal crops.²² We know that between 1860 and 1920, Catalonia, and especially the province of Barcelona, saw the consolidation of its early industrialisation. Thus, we need to establish with some accuracy the margin of variation in population density from which we can still expect a positive relationship between population growth and vineyard specialisation, in order to differentiate them from an upper threshold of population densities beyond which the link between the two variables may become insignificant or even negative.

We take the amount of labour required to cultivate a hectare of vines compared with the labour needed to cultivate a hectare of cereals as the crucial data to estimate the range of land-labour ratios that could determine a factor endowment favourable to viticulture. We know from an earlier detailed study on the Land-Time Budget Analysis (LTBA) of a rural municipality in the province of Barcelona that around 1860, one hectare planted with vines required 73 man-equivalent working days a year, whereas in a rather intensive cropping of cereals and legumes without fallow in the same area, only 42 working days were needed at that time.²³ A detailed study on the economic accounting of a vineyard farm in the same province between the 1920s and 1930s tells us that technological innovations adopted after the Phylloxera plague had increased by 30 per cent the labour required by the new viticulture, up to 94 annual man-equivalent working days per year per hectare.²⁴ However, other contemporary sources tell us that the extensive cultivation of cereals with fallow practiced in inland Spain only required 25 working days per hectare a year.²⁵ This was also the case in the Catalan province of Lleida, were population densities matched those in Castilla during 1860–1920.

Assuming that the active agricultural population worked on average eight hours a day during 240 days a year, and that there was the same 0.37 ratio of active agricultural people over the total population that the LTBA study revealed for Barcelona around 1860, we can calculate from the labour required to grow a hectare of vines that the optimal population density ranged between 0.8 and 1 hectare of cropland per person. This would have meant between 82 and 105 people per km² if all the land had been covered with vineyards, which of course is not plausible except in very specific local cases. In order to calculate the mean optimal population density for growing grapes, a proportion of vineyards over the total extension of land must be applied, which varied greatly from one village to another. Taking as a reference the averages of cropland acreage that in Catalonia ranged between 30 and 40 per cent of the total provincial size during the 1860s to the 1880s, the optimal population density for viticulture would have been between 25 and 40 people per km².

This fits very well with the data we have from the available census, shown in Figure 6. Population densities remained around 25 inhabitants per km² in the province of Lleida, which was mainly devoted to cereal crops except during the short-lived wine frenzy following the Phylloxera infestation of French vines. But all the other Catalan provinces already had population densities above 40 inhabitants per km² during 1860–1920. Only in the province of Barcelona did they increase from 94 to 175 people per km², or from 1,978 to 5,662 in the Barcelona district, due to the advance of industrialisation and urbanisation. It is interesting to note that according to Ester Boserup, 65 per km², or 1.5 ha per person in most of rain-fed agricultural areas of the world is the maximum level of population density that can be sustained by a highly intensive agrarian system. Only an urban–industrial economy can maintain population densities higher than that.²⁶

Let us imagine for a moment what it would have meant to rely on only 1.5 ha per person to feed the local population, as well as provide them with fuel wood and pasture, with an organically based intensive agricultural system, and in a Mediterranean bioregion that is subject to low rainfall, and where the opportunity to keep livestock and obtain manure became increasingly limited. As in any type of organic agriculture, an innovative response had to deal with two difficult side-effects: the scarcity of fertilisers and firewood. The Mediterranean solution of planting vineyards helped to prevent firewood and manure becoming bottlenecks that might have halted the progression towards a more intensive land use pattern. Vines were planted mainly by poorer peasants on poor sloping land, and no manure was applied after planting. However, the specialisation in vine cultivation was only partially maintained, which enabled the polycultural landowners of the typical scattered Catalan farms to use most of what little manure was available on the better soils, which were used primarily for cereals and legumes, together with some fruit trees, vegetables, and hemp. After vintage time, even the green shoots of the vines were used as fodder for sheep, which in turn produced the much-needed manure to fertilise other crops. The pruning of vines could also be used to provide a valuable substitute for increasingly scarce firewood.²⁷

Before the arrival of railways, the high transportation costs reinforced the role played by local and regional endowment of land and labour, both in ecological and economic terms.²⁸ In that sense, the location of every district must have had a deep impact on the economic accessibility of foreign markets. For the same reason, the arrival and extension of railways should have led to a significant reduction in transport costs, which can be taken as a measure of access to distant markets.²⁹ The dataset on time-distances that we assembled clearly shows this drastic reduction of the journey time to Barcelona experienced in Catalonia between 1856 and 1920, as shown in Figure 7. According to our data, in several districts of Lleida and Girona, the arrival of the railway reduced the time-distances to the city of Barcelona by a factor of 4 or 5. On average, the spread of the railway network reduced the time needed to travel from any Catalan district to Barcelona by a factor of almost 3. While in 1856 only 10 districts were less than 6 hours away form the harbour of Barcelona, in 1920, already 24 out of 35 were. After a change of this magnitude, we might expect that the distance to Barcelona ceased to be a critical factor for the location of vineyards. However, a comparison of Figures 4 and 7 reveals that vineyard location did not change so much in spite of the dramatic cuts in transport costs experienced during 1880–1920. This could mean that a path dependency kept alive the comparative advantage previously accumulated by those regions that already enjoyed a vineyard specialisation before 1860.

Figure 7. Changes in time-distances to Barcelona from the Catalan districts, 1856–20. Sources: Own calculations. Time-distances before the railway and until 1856 have been taken from these four references: Anonymous, Itinerario; Bertrán Soler, Itinerario; Frígola, Relación; and Estasen, Cataluña. For 1880 and 1889, terrestrial distances have been calculated with GIS by Marc Badia-Miró based on the existing railroads and roads at the time. They have been turned into time-distances by applying the average speed of 4 km/hour on horseback, 5 km/hour by cart and 20 km/hour by a ‘cheap’ railway, according to Sociedad Económica de Amigos del País de Barcelona, Crisis Agrícola y Pecuaria, p. 87. For 1920, the average railway speed has been increased to 30 km/hour.

HISTORY, MARKET ACCESS, AND AGRO-ECOLOGY MATTER TOGETHER

As noted above, the vineyard specialisation of the Catalan districts could be explained by three main sets of variables: agro-climatic endowment for growing wine grapes, population densities, and time-distances to the seaport of Barcelona as an indicator of market access. We will test the statistical significance of these factors in order to explain the degree in vineyard specialisation at district level during the whole period during 1858-1922. To do this we use panel data and estimate the parameters in Equation 1:

• (1)

The model in Equation 1 aims to explain the percentage of cropland devoted to vineyards (Y_i,t) in each district i during the whole period, taking into account: the agro-ecological variables (AGRECOL_i) such as the indices of Huglin (HUG_i) and Winckler (ETI_i) of climatic suitability for vines, or, alternatively, the weighted mean slope of land expressed as a percentage (SLOP_i) as a proxy of land suitable to cereal crops and vineyards, the market access (MKAC_i,t) indicator assessed by the time-distances in hours to the Barcelona market and harbour (BCNTIMDIS_i,t) following the existing roads and railroads, and population density (POPDEN_i,t) taken as a proxy for factor endowment in land–labour ratios.

First of all, in order to measure the impact of agro-ecological factors on vineyard specialisation in the Catalan districts, we estimate Equation 1 by ordinary least squares regression, incorporating as variables the Huglin (HUG) and Winkler (ETI) indices, together with market access and population densities, or, alternatively, the weighted average of land slopes. The results are shown in Table 2. Columns (a) and (b) show that only population density and the time-distance to Barcelona are significant, while the agro-climatic indices are not.

Table 2. Regressions to explain the upkeep of vineyard specialisation in Catalonia before and after the grape Phylloxera plague

Dependent variable: percentage of cropland devoted to grow vines in the districts of Catalonia in 1858–64, 1885–89 and 1922
	(a) Combined OLS estimates (Barcelona included)	(b) Combined OLS estimates (Barcelona included)	(c) Combined panel data by fixed effects (Barcelona included)	(d) combined panel data by fixed effects (Barcelona excluded)
Note: t-ratios are in brackets; ***1, **5, or *10% statistical confidence interval. OLS, ordinary least squares. Source: Own estimates, using the database discussed in the text.
Constant (CT)	−0.043 (−0.12)	0.40 (5.00)***
Population density, inhab./km^2 (POPDENS)	0.002921 (5.13)***	0.002495 (4.95)***	0.0000663 (1.62)	0.001399 (2.07)**
time-distance to Barcelona, hours (BCNTIMDIS)	−0.00568 (−2.75)***	−0.00586 (−2.99)***	−0.00485 (−2.24)**	−0.00418 (−1.94)*
Huglin Index (HUG)	0.00029 (−0.71)
Winkler Index (ETI)	−0.00017 (−0.56)
Mean slope of land in % (SLOP)		−0.0049 (−2.18)**
Adjusted R^2	0.396	0.415	0.902	0.907
Durbin–Watson	—	—	2.10	2.18
Number of observations	105	105	102	105

It appears paradoxical that the agro-climatic indices are not significant in the tests shown in Table 2. The paradox may be explained after close study of Figures 4 and 6. The higher Huglin and Winkler scores are reached on the coastline, especially in the delta of the Ebro River, or in the inland plane of Lleida. However, most of the Catalan districts with a long-lasting vineyard specialisation were located in the pre-littoral corridor that lies in between these littoral and inland places. There are two important implications: (i) the climate zone well endowed for growing grapes was and still is broader than the area actually exploited; and (ii) although vineyard specialisation developed in districts agro-climatically suitable for viticulture, these were not always the most suitable ones.

The first areas where vineyards were established to make and export brandies during the seventeenth and eighteenth centuries were located along the coastline, near the towns of Mataró and Tarragona-Reus. But later on, most of these early specialised locations abandoned viticulture in favour of other more profitable crops or economic activities, except grape-growing areas that had developed a high-quality brand. Catalan vineyards moved location towards the pre-littoral corridor while table wines replaced brandy as the main export product during the nineteenth century.³⁰ Ironically, vines became more widespread again along the coastline, as well as in the inland plains of Lleida, during the short-lived wine frenzy when Phylloxera first infested vines in France. After the plague, the centre of gravity of vineyard specialisation returned again to the pre-littoral corridor in Southwest Barcelona and Northeast Tarragona provinces.

If we replace the climatic indices in the test shown in Table 2 with the weighted average of land slopes in each district, column (b) shows that the coefficient of this variable is significant but has a negative sign, meaning that vines were not planted in the most sloping districts. In a previous publication, we tested a model to explain vineyard specialisation towards 1860 in all municipalities of Barcelona province. We found that vines used to be planted mainly in poor sloping soils that were not suitable to wheat.³¹ Hence, vineyard location can be better explained at a municipal level by the fact that land is unsuitable for cereals rather than its suitability for vines. Nevertheless, looking at the aggregate data at district level, the result found here is the opposite: vines could not be planted in soils with slopes as high as those found in the Pyrenees and other mountain parts of Catalonia. Including squared slopes in the model changes the sign of both variables: slope becomes positive and square slope remains negative, confirming that moderate slopes favoured vineyard specialisation while very high slopes did not. However, the coefficient of square slope is not significant. We are faced again with a question of ranges and thresholds. A different result may be found if we use a weighted average of the slope for cultivated land only, rather than for the total area. Unfortunately, the available cadastral maps do not cover all the municipalities and districts in Spain before the 1950s. Therefore, the most relevant statistical result obtained here reminds us that in assessing agrological and ecological features, the administrative level of observation matters.

We conclude that natural endowment alone can explain neither the spatial pattern nor the historical trends of vineyard specialisation in Catalonia during the last three centuries, at least at district level. Socioeconomic factor endowment and market access are the main explanatory factors. Following on from this conclusion, we need to analyse changes in these two variables over time. Column (c) in Table 2 shows the results of a second estimation of Equation 1 by fixed effects for all districts. In this case, the constant varies for each district, thus capturing the characteristics of every spatial unit. The result shows that the variable of time-distances for access to markets is significant and has the expected negative sign. This means that commercial specialisation in grape growing continued to be correlated with better access to the city of Barcelona, despite significant improvements in transport facilities. Population density is not a statistically significant variable in column (c). As we discussed the meaning of different ranges and thresholds of population density as a proxy for land–labour ratios above, including squared densities, changes the sign of the variable. Although the coefficient is not significant, this reinforces the suspicion that up to a point, higher densities disfavoured vineyard specialisation. We know that the very high densities in the district of Barcelona were related to other types of urban–industrial economic dynamics since 1860. Therefore, we repeated the exercise by excluding the district of Barcelona. Column (d) shows that population density is statistically significant and has the expected positive sign, which means that up to a point, vineyard specialisation was positively related with higher population density.

ECONOMIC AND ECOLOGICAL RESILIENCE: ANY LESSONS?

We have accounted for the variability in the specialisation in vine cultivation across the districts of Catalonia before and after the Phylloxera plague. Our conclusions stress the path dependency experienced by a comparative advantage that had been previously created through a long-lasting historical process. Viticulture became rooted in the cultural landscape and social fabric of these specialised Catalan districts, and this characteristic reinforced their economic resilience to a sudden external shock like the grape Phylloxera plague. Our conclusions stress the importance of accounting for comparative advantages that are deeply rooted in the differentiated natural, social, and cultural fabric of every landscape. Although no commercial specialisation will last for ever, this kind of socio-environmental base can enhance the resilience of an economic system against exogenous shocks.

The significant statistical results we have obtained can also be seen as an indirect confirmation of the Heckscher–Ohlin explanation of commercial specialisation, which emphasises the relative factor endowment of land and labour. However, our main aim as historians is to understand how these different land–labour ratios arose, and why they were kept in the western Mediterranean bioregion over a long historical period. While the agro-ecological endowments were less mutable, the available labour supply was a result of the relative presence or absence of landless peasants. These poor peasants sought to earn a living working as tenants of a rabassa morta lease on the thin and sloping soils offered to them by landowners.³² This peculiar Catalan sharecropping contract lasted until the death of the vines planted by the tenant. The fact that this leasing system became so widespread might be understood as a collective achievement of a complicated agreement between wealthy landowners and landless peasants. The social conflict over land entitlement between the rabassa tenants and landowners lasted from the eighteenth century until the Spanish Civil War in 1936–39. Nevertheless, the contractual agreements reached between them in the meantime helped to reduce the prevailing agrarian inequality, and channelled the social unrest triggered by this conflict towards creating a more productive rural society.³³ This may also help to explain why the ‘Boserupian’ push of population growth, combined with the growing inequality in land ownership, seems to have played such an important role that deserves to be better analysed in future improvements of the model. Further research is also needed on how to deal with the possible problem of endogeneity that working with these sociodemographic variables may entail.

Footnotes

• 1

  This work is part of the research project on the Hidden Sides of Economic Development. Energy, Land-Use and Global Change in the Western Mediterranean Region (SEJ2006-15108-C02-01/GEOG), directed by Enric Tello at the University of Barcelona, and financed by the Spanish Ministry of Science and Innovation with European Regional Development Fund (ERDF) funds. We thank James Foreman-Peck, Jean-Pascal Bassino, and other participants in the Session Responses of Economic Systems to Environmental Change: Past Experiences at the 25th World Economic History Congress in Utrecht in August 2009, and the pre-conference in Aix-en-Provence in January 2009, for their useful comments and suggestions. We also thank Alfonso Herranz-Loncán for his econometric advice, and Pierre van der Eng for his careful improvements of our English text. None of them are responsible for our own mistakes.

• 2

  Garrier, Philoxéra; Pan-Montojo, Bodega; Paul, Science.

• 3

  Crosby, Columbian Exchange; McNeill, Plagues; Diamond, Guns.

• 4

  Diamond, Collapse, p. 17: ‘i.e., to compare natural situations with respect to the variable of interest’.

• 5

  Garrabou, Crisis Agraria; Van Zanden, First green revolution; Campbell and Overton, Land; Koning, Failure of Agrarian Capitalism; Simpson, Spanish Agriculture; Simpson, Agrarian Crisis; Persson, Grain Markets.

• 6

  Piqueras, Filoxera en España.

• 7

  These technical and commercial improvements were among the pool of innovations that also enabled other European farmers to overcome the agrarian crisis at the end of the nineteenth century. Carmona et al., Viñas; Pinilla and Ayuda, International wine market; Pamuk and Williamson, Mediterranean Response.

• 8

  Planas, Cooperativismo.

• 9

  Agnoletti, Conservation; Tello et al. Energy balance; Cussóet al. Social metabolism.

• 10

  Sánchez and Nadal, Én los origines; Sudrià and Pascual, Financing a railway; Valls, Catalunya atlàntica; Valls, Viticulture et industrialization.

• 11

  Fohlen, En Languedoc; Dugrand, Villes et champagnes; Berger and Maurel, Viticulture; Johnson, Life and the Death.

• 12

  De Vries, A modest proposal.

• 13

  González de Molina, Environmental constraints; Garrabou, Conflict and environmental tension.

• 14

  Wrigley, Poverty; Sieferle, Subterranean Forest; McNeill, Something New; Krausmann et al. Socio-ecological regime transitions.

• 15

  Fischer-Kowalski and Haberl, Socioecological Transitions.

• 16

  Marull et al., Loss of landscape efficiency.

• 17

  Hornborg et al., Rethinking Environmental History.

• 18

  Grigg, Dynamics, 47–67.

• 19

  Williamson, Globalization.

• 20

  The Huglin and Winkler indices are used worldwide to assess the suitability of any region for growing wine grapes, and even to predict the effects of climate change on vineyard location. Tonnietto and Carbonneau, Multicriteria.

• 21

  Garrabou et al. Explaining.

• 22

  Boserup, Population and Technical Change.

• 23

  Garrabou et al. Ecological and socio-economic functioning.

• 24

  Anonymous, La revisió dels contractes de parceria, p. 12.

• 25

  Carrión, Latifundios, p. 324.

• 26

  Boserup, Population and Technological Change.

• 27

  Tello et al. Energy balance and land use.

• 28

  Fischer-Kowalski et al. Modelling scenarios.

• 29

  See for Catalonia Pascual, Caminos de la Era Industrial; for Spain, Herranz-Loncán, Spatial distribution.

• 30

  Valls, Catalunya atlàntica.

• 31

  Garrabou et al. Explaining agrarian specialization.

• 32

  Olarieta et al. Preserving and destroying soils.

• 33

  Garrabou et al. Sharecropping; Garrabou et al. Cambio de usos del suelo.