Flowers of evil: potent chemicals lurk behind some of South America's most alluring blossoms

Natural History, Feb, 2002 by Rob Nicholson

My interest in the angel's-trumpet was piqued in 1996 by a letter from a California collector, who alerted me to the fact that Smith College's own conservatories, where I work as a botanist, had been a hotbed of genetic research in the 1940s and 1950s. A. F. Blakeslee had used Brugmansia and the closely related genus Datura as subjects for research into heredity, and this collector wanted to know if we still had some of the rarer species. After fifty years this might have seemed a futile request, but in fact some still thrived in our huge palm house.

I had been exposed to Brugmansia while taking courses with Schultes at Harvard and now eagerly delved further into this fascinating group of plants. The genus had been a subject of research by a succession of Harvard botanists and students, whose dissertations, reports, and dried field collections held a wealth of data. The best work was done by Tommie Lockwood, who spent a year researching these plants in the Andes and then doing complex breeding trials to decipher the number of species in the wild and their ability to hybridize. (Tragically, Lockwood died in an automobile accident in Mexico while he was leading students on a field trip.) The more I looked into the genus, the more I became hooked. Next thing I knew, I was planning an expedition.

I contacted my collecting partner, Melvin Shemluck, a botany professor at Quinsigamond Community College in Massachusetts and also a former student of Schultes's. Using samples taken from Sibundoy Valley, he had done his thesis on the chemistry of Iochroma fuchsioides--another flowering shrub that is a chemical powerhouse. Mel and I enlisted a third participant, John Bela, who had recently studied botany at the University of Massachusetts Amherst, and together we roughed out an itinerary for collecting new samples from the locations frequented by Schultes and his students. We also wanted to bring back cuttings of Methysticodendron and grow a plant so that Schultes, then in his early eighties, could see it flower. (Years earlier, Schultes had distributed cuttings to various institutions, but we could locate no living specimens.)

In the summer of 1997 we traveled to Quito, Ecuador, and set out down-slope to the sweltering lowlands around Santo Domingo de los Colorados for our first day of gathering. Here we found both the white- and the pink-flowered forms of B. versicolor. (We watched as foraging hummingbirds, finding the huge blossoms too long for their beaks, solved the dilemma by poking holes in the floral tube at the point where the nectary lay.) From there our route took us north into Colombia and on to the town of Sibundoy, in Sibundoy Valley. As we ambled down the main street to get a cup of coffee, trying not to arouse the suspicions of a police garrison on the alert for cocaine smugglers, we quickly found how impossible it is to be anonymous in a small town. Soon everyone knew we were botanicos.

After a night's rest, we headed south on a dirt lane toward the Kamsa lands where Schultes had first seen the rare Methysticodendron. Our innkeeper had told us we would encounter a small botanic garden. Along our route, the density of angel's-trumpets was astounding. Hundreds of them were planted as ornamentals beside humble cottages; others served as living fence posts or as shade trees for pigs and cattle. But no one we asked gave us clear directions to the botanic garden.