French Phylloxera Epidemic: Largest Disaster in the History of Wine

A mysterious blight struck the majority of French grape vines between the late 1850s and the turn of the century, causing enormous damage to the French economy. In the vine districts, wages dropped by half, businesses collapsed, and much of viticulture population emigrated to Algeria and other countries. (1) Vintners used 36,633 tons of sugar to improve the quality and quantity of wine produced in 1888, and imported larger quantities of foreign wines to meet the demand for mixing. The imports were, from Spain, 7,008,000 hectoliters; Italy, 1,082,305 hectoliters; and Algeria, 1,089,000 hectoliters. (2) One hectoliter equals to 100 liters or 26,418 U.S. gallons.

Map of France showing the old province of Languedoc (Rhone Valley), where phylloxera first emerged in France. Source:
http://upload.wikimedia.org/wikipedia/en/c/c9/Languedoc1_province.PNG;:
accessed December 31, 2007.

Rhone valley vineyards, where phylloxera blight first struck in France. Source
http://www.nicks.com.au/upload/image/image_20056221314646960.jpg;
accessed December 31, 2007.

Vintners also compensated for the deficient grape harvest by manufacture of wines from the marc with sugar added, and from dry imported raisins. Of the former, vintners produced 2,388,000 hectoliters of wine; and of the latter, 2,220,000 hectoliters. (2) Marc is the pulpy residue left after the juice has been pressed from grapes.

The grape vine blight in the second half of the 19^th century cost France more than twice the indemnity (5,000 million francs) paid to Germany after the Franco-Prussian war of 1870-1871. (1) What caused this historic agricultural epidemic?

Powdery Mildew

Grape-growers in Europe first developed problems with grape production in the early 1840s. (2) In England, for example, observers noted a white “powdery mildew” (fungus) covering young, growing grape leaves, which was similar in appearance to powdery mildew found on peach trees. Growers learned to control the mildew and produce plump grapes by spreading powdered lime and sulfur on the grape leaves. (3)

Grape leaf powdery mildew. Source:
http://i.ehow.com/images/GlobalPhoto/Articles/2100617/mildew003-main_Full.jpg;:
accessed December 31, 2007.

The same powdery mildew showed up in France on grape leaves where it caused a decrease in wine production by 80% by 1854. (1) Because the grape was so vital to the French economy, growers washed grape leaves with sulphate of copper and imported thousands of foreign grapevines for development of resistant cultivars. (3)

Cultivars and Rootstocks

A cultivar is a cultivated plant that has desirable characteristics distinguishing it from otherwise similar plants of the same species. The French grape growers hoped to create a powdery mildew-resistant grape cultivar from rootstock imported from America. (4)

Diagram of an apple tree comprised of a scion and rootstock grafted together. Note the swelling, which is easily visible at the graft union. Illustration credit: University of Wisconsin. Source:
http://www.extension.umn.edu/yardandgarden/YGLNews/images/scion&rootstock.jpg;:
accessed December 31, 2007.

Rootstock is a plant, and sometimes only a stump, that has an established, healthy root system. It is used for grafting a cutting or budding from another plant. The scion is the plant part being grafted onto the rootstock. The scion is the plant that has properties desired by the propagator, and the rootstock is the working part that interacts with the soil to nourish the new plant. In the case of the French blight, French grape growers imported rootstock from America, onto which they grafted the scion from their native European grape vine species-Vitis vinifera. (4)

Dead Vines in France!

Monsieur Pinarum first noticed in France in 1863 that grape leaves were yellowing or reddening in spring and by July or August were defoliating from the vine. (5) Grape production from these vines was poor. In the year following the defoliation, the entire vine would die! The disease moved slowly but with devastating purpose.

The new grapevine problem was at first called “dry leaf” disease. The first French region attacked by dry leaf disease was in Pujualt in the Gard in the old province of Languedoc in the Rhone Valley of southern France. (3) People seeking explanations for the vine deterioration attributed it to the extreme weather conditions, over-production, soil exhaustion, or God’s wrath. (1)

Entire vineyard infected with phylloxera. Source:
http://www.otagowine.com/phylloxera/damage.jpg;
accessed December 31, 2007.

Grapevine affected by phylloxera in Rutherford, California, 1989. Source:
http://www.enologyinternational.com/pages/gallery.html;
accessed December 31, 2007.

In England in 1863, Westrum described “galls” on the underside of grape leaves. (5) A gall is an abnormal growth on a plant, usually caused by insects but sometimes by fungi or bacteria. The first statement of the grapevine disease in Germany followed two years later. But discovery of galls on the roots of grapevines remained for French botanist Jules Emile Planchon (1823-1888), with the Department of Botanical Sciences at the Montpellier University of Sciences, to first announce, in 1868. (6) He gave the disease the name it still bears: Phylloxera vastatrix.

Grape phylloxera adult female, eggs and nymphs. Photo by Jack Kelly Clark. Source:
http://www.ipm.ucdavis.edu/PMG/D/I-HO-DVIT-AD.002.html;
accessed December 31, 2007.

Grape phylloxera on leaf. Source:
http://www.oardc.ohio-state.edu/grapeipm/images/P7210003;
accessed December 31, 2007.

Professor Planchon and two of his colleagues dug up health, dying, and dead vines. They soon noticed that all the dying vines had small aphid-like insects on their roots. There was great optimism. “All that remained was to determine the insect’s life cycle, direct an attack at its weakest point and the vinifera would be saved. Unfortunately, the life cycle of the insects proved extremely difficult to determine. Indeed, scientists in 1868 discovered the existence of a winged form of phylloxera. What was going on?

Complex Life Cycle of Phylloxera

Grape phylloxera, also known as Daktulosphaira vitifoliae, has a very complex life cycle, as recently described by American entomologists McLeod and Williams. (7)

The phylloxera insects “overwinter either as a winter egg under the bark of older canes or trunks or as nymphs on grapevine roots. The winter egg (Figure 1A [see below]) gives rise to the fundatrix, or stem mother, which moves to a nearby shoot tip and begins feeding. Feeding by the phylloxera elicits gall formation, and the female becomes enclosed within a small, spherical gall on the underside of the grape leaf. This parthenogenetic female is capable of producing several hundred eggs. First instar nymphs, or crawlers, emerge and move out of galls to nearby shoot tips where they begin feeding and thereby initiate formation of new galls. There are three to five generations of foliar phylloxera per season in eastern North America (Figure 1B). Throughout the summer a certain portion of the foliar crawlers move actively or passively to the soil surface. These crawlers may move through cracks in the soil and eventually reach grapevine roots. [Italics added.]

Phylloxera may also overwinter on grapevine roots as first or second instar nymphs. As soil temperatures increase, crawlers resume feeding. Feeding by phylloxera on grapevine roots results in two types of galls. Nodosities are galls formed on small, apical rootlets which are generally thought to result in little damage to the vine. Tuberosities are galls formed on larger, older portions of the root which, if sufficiently abundant, may eventually result in death of the vine. [Italics added.]

From July through October, some root-infesting phylloxera develop wing buds and eventually become fully winged adults. Alates emerge from the soil and deposit two types of eggs, a larger egg which results in a female and a smaller egg which gives rise to a male. These sexual forms mate and the female deposits a single overwintering egg under the bark of older canes or trunks, thus completing the complex life cycle.

American Origin of Phylloxera in Europe during the 19^th Century Blight

The state entomologist of New York in 1856 first described galls on grape leaves, seven years before Monsieur Pinarum described it in France (see above). (5) Furthermore, “[u]nmistakable evidences of its existence reach much farther back, even to 1843, noted one expert. (5) “In later years more or less injury was done, but the true cause of the trouble was not known until the discovery of the “root-type” of the phylloxera in 1868 by Jules-Emile Plouchon, as noted above. (5) In other words, the phylloxera insects in the galls on the underside of grape leaves of American grapevines were a nuisance, rather than grapevine killers. Indeed, root galls are sometimes visible on the root systems of American grapevines.

Phylloxera insects are native to the Eastern United States. How and when did they reach Europe? In 1887, observers asserted that the phylloxera insects in the root galls of diseased French grapevine root systems were the same species as the insects in the leaf galls of diseased American grapevines! (5) In addition, the French vineyards that acquired the disease were “near some American vines which were part of a heavy importation in 1860-the probable time of the introduction of the pest. Undoubtedly, the pest reached France through these cuttings or [root]stocks. The fact of transporting by cuttings is further evidenced by later experience in Germany, Switzerland, and other countries where infection began among American stocks.” (5)

Why Phylloxera Is Deadly for European Grapevines and not America Grapevines

American (Maryland) entomologist Henry Brooks (1838-1918) gave four reasons to explain the comparative difference in toxicity of Phylloxera in Europe and America. (5)

1. “Insects indigenous to a country are frequently kept in subjection by its enemies. Such is the case to a great extent in the Mississippi valley, where the galls of the phylloxera are often cleared of its inhabitants by depredating enemies [e.g., “thrips, tyroglyphus]. This restriction is removed in the new country [e.g., France, Germany], and the pest has full chance for development.
2. The predominating varieties of vines of Europe, and also of California, are of the kind most attractive to the root louse [i.e., Phylloxera], while Mississippi valley produces largely gall-bearing varieties of vines, which to a greater or less extent resist the attacks of the root-louse.
3. The predominance in Europe of the most destructive type, the root-louse, against the gall-louse [leaf-type] in the Mississippi valley,--the one attacking the roots, and affecting the vine permanently; the other attacking the foliage, and producing a transient effect.
4. Probably the chief cause of a comparative greater destruction can be found in the difference in soil, and more especially in the climate; that is, when European countries are compared with districts, like California, cultivating a similar variety of vine. It has been a notable feature in California experience that the spread is usually very slow, and only showing noticeable rapidity in exceptional cases. In our observations (see ‘Report of college of agriculture, 1886’) we have shown that a peculiar growth of roots, induced by late rains, or again by surface manuring, will produce the winged form in great abundance. [Italics added.] But the general climate of California is extremely dry during this growing period, and therefore no such roots are apt to be formed; while in the portions of Europe where the spread has been most rapid, their type of vine being similar to that of our own, a growth of fine surface rootlets is undoubtedly induced by the summer rains, and myriads of the winged-form insects developed and spread to adjoin vineyards. [Italics added.] The effect of fertilizing on the production of similar rootlets is doubtless greater than is usually supposed.” (5)

Controlling Phylloxera

Scientists on both sides of the Atlantic Ocean, and in Australia and New Zealand, tenaciously attacked the problem of grape phylloxera. Scientists with the agricultural laboratory at the University of California in 1882, for example, determined that “grafting the European grape (Vitis vinifera) upon a Calfornian species (Vitis californica) resulted in “greater power of resistance to Phylloxera possessed by the American species.” (8)

In France in 1891, phylloxera was continuing to spread, even invading the champagne districts. (9) The Superior Phylloxera Commission in France reported in 1891, according to one source, “that about 240,000 acres [of vineyards] have undergone defensive measures, submersion being employed in 72,000, bisulphide of carbon in 145,000, and sulphocarbonate of potassium in 23,000. The work is practically at an end in such departments as Herault, Gard, and Gironde, where the American resistant vines have most effectually been used [italics added]; while the wine-growers of Algeria, Spain, Italy, Portugal, Hungary, Austria, and Switzerland, are all battling against it, and are all more or less aided by their respective governments. The advent of the insect in New Zealand has been the cause of much writing and of much legislation there, and the government has been quite anxious to get the best and latest information on the subject.” (9)

Agriculturalist and writer Dr. Charles Valentine Riley at the annual meeting of the Association of Economic Entomologists held in Champaign, Illinois, November 11-14, 1890, wrote the following detailed account about the challenge of controlling the global phylloxera scourge: (9,10)

“During the more than twenty years’ struggle in France against the species, innumerable remedies have been proposed, most of which have proved to be absolutely valueless. A few measures have been devised, however, which, under proper conditions, give fairly satisfactory results. These consist in (1) methods which avoid the necessity of direct treatment, comprising the use of American stocks and planting in sandy soils [italics added]; (2) the employment of insecticides (bisulphide of carbon, sulphocarbonate of potassium, and the kerosene emulsions); and (3) submersion.

“It was early found in the history of this Phylloxera that most of the cultivated varieties of American grape-vines, as also the wild species, resisted or were little subject to the attacks of the roof form (radicicola) of the Phylloxera; although the leaf-gall form (gallicola), which in point of fact does little if any permanent damage, occurs in greater numbers on many of our [American] wild and cultivated sorts than on the European grape-vines., which are all derived from the single species Vitis vinifera, and which are so exceedingly subject to the attacks of the root form. This fact was first noticed in France by M. Laliman of Bordeaux, and later by Gaston Bazille of Montpellier, and was independently proved on a more extended scale by my earlier investigations in the United States. The use of American stocks upon which to cultivate the susceptible European varieties has resulted in an enormous trade in certain American seeds and cuttings, and now supersedes all other methods against the Phylloxera.

“It was my privilege and pleasure to spend a week in August, 1889, among the world-renowned Medoc and Sauterne vineyards of the Bordeaux district in France. Here, by virtue of the rich alluvial soil, and the ease with which the chief vineyards can be submerged, the Phylloxera has made slower headway, and the opposition to the use of American resistant stocks has been greatest. [Italics added.] Yet they have finally vanquished prejudice, and are, either form necessity or choice, rapidly coming into general use. When I say ‘choice,’ I mean that even where the French vines yet do well, and the Phylloxera is kept in subjection by other means, it is found that greater vigor of growth and increase in healthfulness and yield of fruit results at once from the use of the American stocks.

“Without going into a lengthy discussion of the subject of wild American species, those of practical importance to the grape-grower are the following: V. oestivalis, V. riparia, and V. albrusca...Of the many valuable hybrids obtained from the American species of Vitis which are serviceable as stocks, the more important are the Elvira, Noah, and Vialla. The last named, of all the resistant varieties, gives the greatest percentage of successful grafts, and is admirably adapted for grating on cuttings.”

Riley then mentions the huge monetary award offered by the French government to whoever discovered the remedy for grape phylloxera:

“Considering the effective way in which the ravaged vineyards of France have been and are being redeemed by the use of resistant American stocks, and considering the efficacy of some of the direct remedies discovered, it is passing strange that no disposition has ever been made of the premium of 300,000 francs offered in the early history of the trouble by the French Government. It cannot be awarded to any one person, but should be distributed among those whose labors and discoveries resulted in the several feasible and satisfactory methods of coping with the insect.” (9) The French government never disbursed the award.

French Viticulture in Algeria

Algeria is one of the oldest wine-producing countries in the world, dating back at least to the Phoenicians (1200 BC to 900 BC). Under Roman rule, winemaking in Algeria continued until non-alcohol-drinking Muslims conquered North Africa in the 7^th and 8^th centuries. For more than 1,200 years, Arabs grew grapes in Algeria for table fruit only. When the wine-producing and wine-drinking Catholic French invaded Muslim Algeria beginning in 1830, as described elsewhere, grape-growers were free once again to cultivate grapes for wine-making in the sunny dry plateaus just inland from the Mediterranean coast of Algeria. (11-12)

The wine blight in France in the last half of the 19^th century provided a perfect window for large numbers of French grape-growers to immigrate to Algeria. After some partial failures because of lack of experience with the different climatic and other conditions, the wine industry in Algeria became a great success. The vintners invigorated the Algerian economy, making wine exports 44% of total exports by revenue until the Algerian war for independence (1954-1962), after which vintners and almost all other Europeans departed Algeria presumably for good. (13)

Algerian wine-making has started up again since the Algerian war for independence. The Muslim government of Algeria understands the need for a strong economy and actively promotes wine growing to provide export income. (14) “Algeria has never known the Phylloxera, so while the French vineyards were practically decimated by the epidemic in the middle of the 19th century Algeria retained its stock. Even today the country’s diverse varieties are protected from the disease by the sandy soil which stops the proliferation of the insect,” notes one report produced on behalf of the Algerian government. (14) Some 75% of the national production is exported, which raises the question as to who among the Algerian population is drinking 25% of the national production. (14)

The Algerian government is particularly anxious to take their wines to United States’ market “because we know that when you are on the American market you are in all the markets of the world,” says Said Mebarki. He continues, “We have our own special character-we will be making single variety wines, but today we are exporting our own wines which have their own qualities and are well known and have a certain quality price ratio. Our wines have their own characteristic taste which comes from the soil and the sun, the heat.” In 1999, the Algerian government was anticipating production of 1,500,000 hectoliters of wine in 2006. This amount compares to the export by the French émigré vintners in Algeria in 1938 of 22 million hectoliters of wine! (14)

Grape Phylloxera Control Today

The grape phylloxera epidemic began in the mid-1800s, but it continues with force even today. It is a nagging problem in the wine industry. American entomologists McLeod and Williams note,

“Feeding by root phylloxera on European grapevines, Vitis vinifera L., is potentially devastating and nearly destroyed the French wine industry in the late 1800’s. The epidemic was eventually brought under control by grafting V. vinifera scions onto resistant American, Vitis labruscana Bailey, rootstocks. A major resistance breeding program conducted in Europe against grape phylloxera resulted in grape cultivars commonly referred to as French-American hybrids. French-American hybrids are important in eastern North America for wine production, but they are particularly susceptible to foliar grape phylloxera.

“Widespread planting of French-American hybrids in eastern North America has resulted in a heightened awareness of foliar phylloxera. Foliar phylloxera reduce net photosynthesis of grape leaves. Leaf galling by grape phylloxera causes distortion, necrosis, and premature defoliation of French-American vines. Premature defoliation may delay ripening, reduce crop quality, and predispose vines to winter injury. Grapevines heavily infested with foliar phylloxera may contribute to root infestations. Research indicates that high population densities of foliar phylloxera can result in a reduction in yield and quality of the crop. Populations must reach very high densities before yield is affected, and in most years yield will probably not be affected. It is not known, however, what impact infestations by the insect year after year have on the overall health and vigor of the vine.

“Few chemicals are registered for control of foliar grape phylloxera. Thiodan (endosulfan) is the standard for commercial growers, but no compounds are registered for homeowner use against grape phylloxera. (Endosulfan does burn some cultivars.) In addition, phylloxera crawlers can be spread on vineyard equipment. Therefore, when mechanical operations are performed, equipment should not be moved from an infested block to a noninfested block. Infestations may also originate from wild grapevines near the vineyard, so these areas should be monitored carefully. Wild grapevines near the borders of vineyards should be destroyed if possible. A number of natural enemies feed on grape phylloxera, but none are commercially available for use in biological control programs.” (7)

Sources:

1. “Great French Wine Blight”, p. 3. Published in Wine Tidings No. 96, July/August 1986. Available online at http://wampumkeeper.com/wineblight.html; accessed December 28, 2007.
2. “Notes and News”. Science, July 26, 1889, Volume XIV, No. 338, p. 59.
3. “Powdery, Phylloxera, Downy, Oh My! Millardet discovers Bordeaux Mixture an Early Fungicide (1885)” at http://www.plant.uga.edu/labrat/millardet.htm; accessed December 28, 2007.
4. Gail Nonnecke: “Grape Cultivars for Iowa”, January 26, 2002. Available at http://viticulture.hort.iastate.edu/info/pdf/grapecultivars.pdf; accessed December 27, 2007.
5. Henry Brooks: “Phylloxera”, Science, May 7, 1886, p. 417.
6. “Short Biography of Jules Emile Planchon” at http://www.victoria-adventure.org/water_gardening/biographies/jules-emile_planchon.html; accessed December 27, 2007.
7. Murdick J. McLeod and Roger N. Williams: “Grape Phylloxera”, Ohio State University Extension Entomology. Available at http://ohioline.osu.edu/hyg-fact/2000/2600.html; accessed December 28, 2007.
8. “California Agriculture” section. “Report of the professor in charge to the president, being a part of the report of the regents of the university. 1882. Sacramento, State, 1883. Science, June 22, 1883, Volume I, Number 20, pp. 578-579.
9. C.V. Riley: “The Outlook for Applied Entomology”, Science, January 9, 1891, Volume XVII, No. 414, pp. 16-18.
10. “Charles Valentine Riley Collection”. Available at http://riley.nal.usda.gov/nal_display/index.php?info_center=8&tax_level=4&tax_subject=158&topic_id=1982&level3_id=6419&level4_id=10871&level5_id=0&placement_default=0&test; accessed December 29, 2007.
11. SEMP Biot Report #486: “Abd-El Kader and the French Conquest of Algeria” (December 11, 2007) at http://www.semp.us/publications/biot_reader.php?BiotID=486; accessed December 27, 2007.
12. SEMP Biot Report #487: “French Colonization and Decolonization of Algeria” (December 26, 2007) at http://www.semp.us/publications/biot_reader.php?BiotID=487.
13. Mahfoud Bennoune: The Making of Contemporary Algeria (1830-1987). Cambridge University Press, p. 63.
14. “Wine growing provides export income: Viticulture has long standing history.” Algeria: A Special International Report. Washington Times, July 2,1999. Available at http://www.internationalspecialreports.com/archives/99/algeria/28.html; accessed December 29, 2007.