Phylloxera's Effect on Scotch, Cognac, and Texas Whiskey (with Robert Likarish of Ironroot Republic Distillery)

Did the French Wine Blight of the 19th century elevate scotch's reputation?

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Show Notes

What does a microscopic North American aphid have to do with scotch and Texas whisk(e)y? Quite it bit it seems. And a man name T.V. Munson is the common denominator.

From his home in Denison, Texas, Thomas Volney Munson was summoned to save the Cognac region of France from a vine damaging insect called Phylloxera.

And his work would inspire two brothers who would build their distillery and name it in honor of their local hero - a hero that the Cognac region still reveres today.


Thomas Volney Munson loved grapes. Loved grapes so much in fact that he devoted a large portion of his life to them. Born in Astoria, Illinois in 1843, his first job was as a teacher, but his love for horticulture drove him to attend the University of Kentucky in Lexington. Upon graduation, he became a professor there, teaching science.  

But T.V., as his friends would call him, wanted more. He knew his life would be best spent following his passion - those little white, green, red, and purple spheres that he called “the most beautiful, most wholesome and nutritious, most certain and profitable fruit that can be grown.”

First he and his wife moved to Nebraska, where T.V. found work as a horticulturist and a viticulturalist (a fancy name for someone who studies grapevines). But Nebraska’s weather was too extreme and unpredictable - going from harsh drought filled summers to hard cold winters - and the grasshoppers were intense.

But it was in Nebraska that he would start to notice a trend. Wild native grape vines were less susceptible to disease than imported vines. Little did he know, this discovery in the midwestern plains of America would be the seeds of an answer to a problem that was literally plaguing Europe. 

After three years in Nebraska, T.V.’s brothers William and J.T. lured him south, to the state of Texas and a little town near the Red River called Denison. Here he would find comfort in family, a more predictable climate, plenty of wild grapes (during his time in Texas he studied over 300 grape varieties), and a jumping off point for his grape research that would lead him to Mexico and over 40 states.

When I recently visited Denison, Texas, I had the honor of interviewing a fan of T.V. Munson’s work - Robert Likarish, part-owner of the Ironroot Republic Distillery whose name Ironroot pays homage to T.V. who became known as The Grape Man of Texas. I asked him what got him so interested in Munson.

ROBERT: It's it's all the like things around the little anecdotes that you hear from all the different places and every time the stories told that again he was a little bit more of an eccentric of the brothers again we talked with the family he was the other ones were very much business-focused here with the railroad and everything making money here and he was the brother that was researching an agriculture and trying to figure out how to grow you know grapes improve the American great varieties and again he was the old bell brother which is kind of just like an endearing thing And then that he was working with the US department of agriculture and he was sending all these papers to the Smithsonian and other places about grapes and how to and the grapes from the region in the US and and the French the Smithsonian didn't really know what to do with all these papers on grapes because no one really cared all that much about rape varieties 

Well, if most of the people at the Smithsonian weren’t quite sure what to make of this odd little man and all of his viticulture research, there was one very important man at the Institute that was making a mental note about T.V.’s work. Within a couple of years, a French professor would show up on T.V. Munson’s doorstep with a major question - how to rid the French Cognac region of an insect that was decimating their vineyards. 

Did Scotch Whisky Benefit From An American Insect?

There is a long held belief among scotch whisky experts that when a North American insect called Phylloxera devastated the French Wine industry in the 19th century, the subsequent brandy shortages drove the English upper crust into the waiting arms of scotch whisky - thus elevating scotch to the reputation it enjoys today. It is a statement that has been uttered so many times, that I myself have passed the theory off on several occasions. But as my whisky studies have shown me - question everything!

And this theory raises several questions. Was scotch really not a popular drink for the English upper crust before the Phylloxera epidemic? Did this bug actually originate in North America? And how did this small Texas town of Denison become inextricably linked to the French wine industry and end up the sister city of Cognac, France?

The Wine Plagues of Europe

To understand the impact of Phylloxera and the Great French Wine Blight on scotch whisky, it's important to dive into some misconceptions of the era. While it is true that Phylloxera - a microscopic aphid or insect - forever altered the standing of French wine, it actually wasn’t the first plague to run roughshod over the grape vines of France in the 19th century - there were actually four plagues.

Two were handled quickly and were overshadowed by the Phylloxera infestation. One was a case of downy mildew called peronospora that occurred in 1878 and the other was a case of black rot ten years later.

But the most damaging predecessor to the Phylloxera crisis was the spreading of a white powdery mildew over a large swath of the vineyards in France. Called Oidium, it is thought this pesky fungal disease was unintentionally brought to France through England via North America. It damaged the grapes by their color and character greatly reducing usable crops. And its effects were catastrophic. Over seven years, wine production decreased in France from 54 million hectolitres in 1847 to 11 million in 1854.

However, the reason this deadly period for French wine is mostly forgotten is because chemistry found a safe and effective cure, sulfur dusting. And within a year, a great French wine revival began. 

But just eight years later in 1863, a farmer in the southern Rhône region of France started complaining that his vineyard was being destroyed block by block by a new more mysterious disease and he was at a loss for what to do.

Theories were tossed around, including a grape vine equivalent to tuberculosis, but Paris seemed to be in no hurry to investigate. 

Over the next three years the insect spread unmolested throughout southern France and growers decided to take matters into their own hands. They formed a three man commission that included a passionate researcher Professor Jules-Émile Planchon of Montpellier University. 

They started by examining the dead roots but all they could find was rot. Then it was suggested that they check a nearby healthy plant. Perhaps they could discover a weakness in the plant. What they found was a swarm of microscopic yellow insects feeding on the healthy plant. 

Thinking he'd found the source of the blight, Planchon put together his findings and sent them to Paris. But to his dismay, the findings were denounced, as Planchon and his compatriots were not considered insect specialists and the idea that this small insect could do such damage was preposterous.

Undaunted, Planchon consulted his brother-in-law, a French entomologist named Jules Lichtenstein and another named Victor Antoine Signoret. Lichtenstein suggested this little aphid was potentially of North American origin. The problem with this theory was that the North American aphid snacked on leaves, while these were attacking the rootstocks of the vines.

Around the same time in England, an Oxford University entomologist Professor John Obadiah Westwood revealed that some six years earlier he had completed a study noting these little yellow insects had already been snacking on the leaves of English grape vines - his study being performed the same year as the first outbreaks were noticed in France.

But if these bugs were truly of North American origin, how were they getting to Europe? And why was this problem only unveiling itself in the mid-19th century?

A first thought might be a sudden interest in American grape varietals by Europeans. But this New World plant species fascination can be traced all the way back to 1000 AD when Leif Ericcson landed in modern-day Canada and proclaimed his fascination for what appeared to be grapes in a land he would name Vineland. And as the French moved into Canada, they brought their vines with them. Unfortunately though, these attempts normally ended in failure. And it is likely that vines were shipped back and forth between continents to determine why the French vines couldn’t survive in North America.

No, the more likely culprit was the invention of the steamship. Nature simply wasn’t ready for the speed of transportation - and insects and fungi that couldn’t survive months at sea, were much more able to survive weeks at sea. 

While Planchon was seeking answers to this little yellow invader, France was caught between a war with Prussia and it’s own political end fighting. A chemical solution was suggested. A highly combustible agent called carbon disulfide or CS2 was suggested. Its job was to asphyxiate the insect, but it was not only tedious to apply, it was costly. 

One farmer in 1869 had seen success when a flood covered his vineyard for weeks and in the aftermath, he saw his crops return. Flooding was suggested as a means of controlling the insect, but it required 40 days of submersion and it just wasn’t a feasible solution. Then, a reward of 300,000 Francs was proposed for the person who could find the solution to the problem.

Suggestions went from prayer and exorcism, to beating clubs around the vines to annoy the insects away, to burying frogs under the vines, spraying them with urine, packing them with sand, or burning the vines. Nothing had a lasting effect.

But as radical as these solutions sounded, what an American entomologist and Planchon’s team were about to suggest was unthinkable to the French.

Charles Valentine Riley

From his office in the state capital of Jefferson City, Missouri’s state entomologist Charles Valentine Riley was keeping a watchful eye on the plight of the French. Reading Planchon and Lichtenstein speculation of a connection between the aphid ravaging French vines and the aphid that consumed American leaves, he sent the American aphid to the French team to experiment. What they found was that indeed, these were the same insect. And what was curious is that when they placed the infected American grape leaf next to the European vine, the aphids migrated to the European roots.

So why were these little destructive creatures avoiding the American rootstocks? It takes an understanding of both Phylloxera and the makeup of the European vine versus the American vine.

Phylloxera and European Vines

As I mentioned before Phylloxera are little yellow microscopic insects, called aphids. Aphids are soft sap sucking insects with long mouth appendages that penetrate plants, sucking out sappy nutrients. 

What is fascinating is that Phylloxera don’t actually kill the vines when they begin syphoning out the sap. The damage occurs when the wound in the vine’s rootstock is left untreated and the exposed section begins attracting deadly bacteria. So Phylloxera are simply a catalyst for the demise of the vine.

The female aphid lays eggs on the bark and they lay dormant through the winter. By the next year, the offspring hatch and begin feeding on the vine’s sap. A single female can lay up to 200 eggs, so a couple of Phylloxera can do major damage in the course of a few seasons. 

What Makes European Vines Different? Planchon/Riley

But why are American rootstocks avoided by these insects? It all comes down to the evolution of the species. This enemy attacked the American rootstock long enough that the nature of the vine’s sap became sticky and it would clog the mouth of the insect while it tried to feed. And even if the aphid succeeded in wounding the rootstock, the American vine learned to immediately form a protective layer to keep dangerous bacteria at bay. This is why the Phylloxera on American vines attacked the leaves - it was all they could safely feed on. European rootstocks had not developed this natural defense and were left exposed as easy prey. 

The solution that was proposed by Riley and Planchon was the grafting of American rootstock onto a European vines. It could create a natural defense, without making a significant alteration to the grape. Compared to the alternatives, which included replacing French vines with American vines or hybridization that could alter the nature of the French grape this was a far superior solution. But burying frogs was a symbol for how opposed to these tactics the French really were. The American grape was seen as inferior and some were ready to sacrifice regions of grapes to avoid contaminating France’s prized crop. The government went as far as to make grafting American rootstocks illegal, yet some farmers braved the risks and began importing the rootstocks to save their vines.

Denial continued through the first half of the 1870s. It was suggested that the insects were just the byproduct of some unknown disease. The weakening vines were attracting the bugs who simply finished the job.

The Rules Loosen and an Industry Recovers, But a Few

But by 1878, the French wine industry was on the brink of total destruction. The choice was coming down to succumbing to grafting or potentially losing all of their grape varietals. Laws were passed to allow for grafting, first in the south of France, where Parisians felt more inferior grapes came from, but finally the laws were changed in the north as well. 

Soon, grafted vines were fending off the yellow scourge and by 1884, Riley, who had become the Chief U.S. Entomologist, was being recognized by the French government with a spot in the French Legion of Honor.

But the work wasn't over. There was a lot of trial and error. Some of the American rootstocks that were grafted seemed as defenseless to Phylloxera as their European cousins, and high pH levels in some French soil were inhospitable to the supplied rootstocks. 

One of those areas that was hindered by soil conditions was Cognac. And by 1887, they had reached their breaking point and reached out to the French Ministry of Agriculture, who appointed Dr. Pierre Viala, a professor of viticulture at the agricultural school in Montpellier to travel the United States to see if he could find an expert that could provide a suitable rootstock. Dr. Viala had discovered the Black Rot plague just a few years previous.

He arrived in America in June and his first meeting was with Charles Riley in Washington DC. By this point, Riley had expanded his research and was stationed at the Smithsonian Institute. With Dr. Viala in desperate need of a viticulturist Riley started thinking about the stacks of documents he’d been receiving from out west..

ROBERT: when the French came looking and that they ended up helping get him in touch with this guy in Denison Texas that was writing these things on grapes that didn't really care about it all these coincidences and he was in the right place the right kind of crazy person at the right time with the right grapes that were growing in limestone rich soils that can handle the pH and everything that the the French were dealing with it was the right solution.


The French Cognac Solution

With the Frenchman Viala in his home, T.V. Munson recalled a lime tolerant grapevine that could survive the elevated pH levels present in the Cognac soil. Dog Ridge in Bell County, Central Texas was just the place. 

The rootstocks he suggested did the trick and the Cognac region was so pleased by the results that they supported T.V. 's election to the Order of Agricultural Merit in the French Legion of Honor. 

The Aftermath

For the French wine industry, the blight had several consequences. First, France would never reach the level of grape production it had prior to the four plagues. Second, during those years of Phylloxera, France went from being the largest exporter of wine to the largest importer - and while other countries were quicker to battle the insect, France fell back into the pack and struggled to regain its dominance. And third, it brought about an era of faux wines and brandies which temporarily damaged the reputation of French wines.

As for the aphid, it is almost everywhere in the world. Chile has one of the few remaining untouched regions as well as a couple of French holdouts. Grafting is common practice and has even had to be used to save parts of California’s wine industry multiple times.

Effect on Scotch Whisky

So how did this all play out for the popularity of scotch whisky among English gentlemen? The thing that is credited widely with bringing acceptance to the spirit around the world.

Well, Chris Middleton of Whisky Magazine wrote a very revealing article on the subject. He suggests that as of 1825, of the 20 million gallons of spirits consumed in Britain, 84 percent were British spirits, mainly whisky. By 1860, whisky consumption was thirteen times that of brandy consumption in Britain.  During the first half of the 19th century, rum was the main, but still distant competitor of whisky.

It is more likely that the Excise Tax of 1823 that made whisky cheaper to create legally, the Spirits Act of 1860 that opened the industry to blending malt and grain alcohol, the Coffey column still, the era of whisky speculation brought on by the Pattison brothers, and the incredible marketing ability of men like Tommy Dewar did more to popularize scotch whisky than an invading insect in France could. 

And to suggest that English gentlemen somehow had a sway over the opinions of the general public’s drinking preferences is a stretch. If they held that much power, then why was brandy not more popular in the years preceding the Great French Blight?  It’s a pretty thin argument - but one that doesn’t seem to die.

Denison and Cognac

And what legacy did Thomas Volney Munson leave behind? Well, the town of Cognac never forgot his contribution to their storied industry. Several times, emissaries have visited the town of Denison in appreciation for what T.V. Munson means to Cognac. And in 1992, Denison, TX became Cognac's sister city. Fitting, since Denison’s other favorite son, General and President Dwight David Eisenhower was the man who was a driving force in the establishment of Sister Cities International in 1956.

And Munson’s legacy would play an additional part in Denison’s future. 

ROBERT: I want to undergrad at Austin college which is over in Sherman Texas and while I was there we had to do as part of the leadership program there and we had to do research basically on texoma and that was one of the stories that came up and it was really like and so I didn't really dive deep into it but we got into again why the Grayson college has a viticulture school and why they have a vineyard there and everything and so I knew that he was important it was kind of a really kind of cool story

But it wasn't until we actually were decided we were going to sit down roots and start actually building a distillery and coming back to Texas to do it that I got a phone call from one of my professors and was like if you're doing this you need to come out here and check this out and for us like the moment that we got here was kind of like the perfect moment because really going to the school talking into the professors talking to several of his descendants in town and talking about kind of our background and what the way we had been taught to make spirits and that connection to cognac it just it was kind of like the right right place for us to be and it felt like that was the place that we should be and that's kind of how we ended up in Denison, cuz people asked us all the time like why Denison of all places because of the connection to cognac and that was that's what intrigued us from very beginning.

So, what about the name Ironroot?

ROBERT: So the original name we were working on for the distillery was going to be Red River republic was the way we were going to go with it and there was just something that it just felt almost a little too generic like there's a lot of things are named Red River up here and it was we wanted to kind of tie it again type back into us into the the city where we're coming from and all all those things are what made sense to us and that's why we decided to kind of do it in honor of TV month

And just like the grapes spoke to T.V. “Iron” Munson, the passion for cognac, and the French dedication to their spirits continue to inspire Robert and his brother as they integrate those traditions into their whiskeys:

ROBERT: there's so much thought behind every single step in the way that they do things that that Jonathan I jump head deep into that style and that that way of doing things and then coming from that that's when we were looking at cities to to put the distillery in and then we saw the history of Denison and that light bulb from what I've learned at school click back on we're like nope that's that's where we're going doesn't matter about anything else this is the city

Whiskey Lore is a production of Travel Fuels Life

Research, stories and production by Drew Hannush

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I had an amazing trip to Ironroot Republic in Denison and thank Robert and his family for their hospitality and a taste of some amazing things they have coming down the pike. Check out my conversation with Robert on an x20m coming up this Thursday. And until next time...

Santé, Cheers, and Slainte mhath