The Drunken Botanist: The Plants that Create the World's Great Drinks (46 page)

BIRCH

Betula papyrifera

betulaceae (alder family)

A
mericans might not have invented birch beer, but we certainly perfected it. Birch trees are found all over North America, Europe, and Asia. Over the centuries they've been put to use as lumber and paper, as dye and resin, and as medicine. Archeologists have turned up drinking vessels in Europe dating back to 800 BC that contained birch sap residue, suggesting that it was used in wine making just as honey was.

Starting in the early seventeenth century, several scientists wrote about the use of birch sap in medicinal, or purely recreational, liquors. Flemish physician Johannes Baptista van Helmont wrote that birch sap could be collected in spring and poured “into the Ale, after the greatest settlement of its boyling or working, which Wines and Ales do voluntarily undergo in Hogs-heads.” He recommended this naturally fermented sap as a treatment for ailments of the kidneys, urinary tract, and bowels.

A few decades later, in 1662, John Evelyn offered this recipe in
Sylva,
the first book on forestry ever published: “To every gallon of birch-water put a quart of honey, well stirr'd together; then boil it almost an hour with a few cloves, and a little limon-peel, keeping it well scumm'd: When it is sufficiently boil'd, and become cold, add to it three or four spoonfuls of good ale to make it work (which it will do like new ale) and when the yeast begins to settle, bottle it up as you do other winy liquors. It will in a competent time become a most brisk and spiritous drink.”

But it was the American paper birch—the aptly named
papyrifera
—that yielded abundant, sweet sap just when early colonists could most use a drink. The settlers watched Native Americans tap birch trees in spring and capture the sap, but what they didn't see them do was make alcohol from it. In spite of abundant sources of sugar and
grain, northern tribes did not seem to develop a tradition of brewing alcohol the way southwestern and Latin American native people did. But Europeans knew a good source of alcohol when they found it; they mixed the sweet sap and bark with water, honey, and whatever spices they could obtain to make a mildly alcoholic beer. Sassafras was often an ingredient; from this tradition the drink, sarsaparilla, became popular in Pennsylvania Dutch country.

By the time Prohibition drew near, brewers were creating non-alcoholic versions, called soft drinks, to get around the ban. Nonalcoholic birch beer remained a regional specialty throughout the twentieth century. Today the flavor returns in Root, the Pennsylvania-made liqueur based on the flavor of early American bark and root brews. A few wineries in the Scottish Highlands specialize in birch wine, and a Ukrainian vodka distiller employs the flavor in its Nemiroff Birch Special Vodka.

Birch sap can be used to produce xylitol, a natural sweetener that has been found to fight tooth decay, and the bark of some species are high in methyl salicylate, the primary constituent in oil of wintergreen. And as usual, the early physicians who prescribed the bark weren't entirely wrong: a birch extract called betulinic acid is being investigated as an anticancer drug.

CASCARILLA

Croton eluteria

euphorbiaceae (spurge family)

T
his small, highly fragrant tree must have seemed like a natural addition to spirits. The bark's essential oil contains many of the same compounds found in pine, eucalyptus, citrus, rosemary, cloves, thyme, savory, and black pepper, making it attractive not just as a flavoring but as a bass note in perfumes as well.

The cascarilla tree is native to the West Indies and was described by Europeans in the late eighteenth century as part of a wave of botanical exploration. Any aromatic tree bark from the New World was being evaluated for its medicinal possibilities; this one was put to use in bitters and tonics of all kinds. It was originally described as a silver-barked tree, but botanists soon realized that the white color came from lichen that colonizes the tree. Under the lichen is a dark, corky bark that was used as a brown dye. Tiny sprays of pinkish white flowers and dark, glossy leaves make the tree an attractive specimen, but like other members of the spurge family (including poinsettia) the sap can be very irritating to handle.

Cascarilla bark continues to be an important ingredient in bitters and vermouth, and is rumored to flavor Campari as well. It has long been an additive to tobacco; when cigarette makers were required to disclose their ingredients in 1989, cascarilla was still on the list.

CINCHONA

Cinchona
spp.

rubiaceae (madder family)

N
o tree has had a more important role in the history of cocktails than this South American species. The quinine extracted from cinchona bark doesn't just flavor tonics, bitters, aromatized wines, and other spirits. It also saved the world from malaria and put botanists and plant hunters at the center of several global wars.

Twenty-three different trees and shrubs make up the
Cinchona
genus, most of them sporting dark, glossy leaves and white or pink tubular, fragrant flowers visited by hummingbirds and butterflies. The reddish brown bark was used as a medicine by Andean tribes. They treated fevers and heart problems with it, and perhaps malaria—although some historians believe that malaria was introduced to South America by Europeans, who had suffered from it for centuries.

Jesuit priests discovered its efficacy against malaria in 1650, but it was a half century before Europeans grasped the importance of the bitter powder and started sending ships to South America to load up on felled trees. The locals were understandably concerned about the plunder of their forests and worked together to conceal the location of the trees.

Not every species of cinchona yields a potent dose of quinine, and botanical literature is full of misidentifications and misnamings of the trees. In 1854, a gorgeous book called
Quinologie
was published in Paris with hand-colored plates illustrating the different varieties so that pharmacists could tell the types of bark apart. We now know that
Cinchona pubescens
supplies the highest dose, as does
C. calisaya
and a few hybrids. While it may seem that
C. officinalis,
with its official-sounding name, would be the standard for quinine production, it actually contains very little of the drug.