THE BOTANY OF SALVIA DIVINORUM (LABIATAE)

Previous Research

    In 1963, Carl Epling placed cuttings of Hofmann and Wasson's original type collection of S. divinorum in the University of California, Los Angeles (UCLA) Botanical Gardens. Epling never saw these plants flower in the gardens at UCLA, and mistakenly described them as having blue corollas. The source of this error is made apparent by Hofmann (1980), who recalls the time he and Wasson received the plant material:
oldwoman "From an old Curandera, a venerable woman in a strikingly magnificent Mazatec garment, with the lovely name Natividad Rosa, we received a whole bundle of flowering specimens of the sought-after plant,... [she would not] tell us where she had gathered the leaves. They grew in a very, very distant forest valley. Wherever she dug up the plant, she put a coffee bean in the earth as thanks to the gods... We now possessed ample plants with flowers and roots, which were suitable for botanical identification... The plants had blue flowers crowned with a white dome..."

    In fact, the white dome referred to by Hofmann was the corolla, which, in the specimen described, had apparently not yet opened. Likewise, the illustration of S. divinorum in Schultes and Hofmann (1980) includes only flowers in bud, and the artist's rendition of the individual flower parts emphasizes the mistake: the stamen, style, and corolla are each drawn as they appear before the flower opens. Hofmann and Wasson, neither of whom had any idea what the flowers of this Salvia look like, did not realize what they described as "blue flowers, crowned with a white dome" were actually blue calyces with unopened white corollas. The mistake survived in Epling and J tiva's (1962) original description of the species because they never themselves saw living flowers, and the white corollas turn brown upon drying. Diaz (1975), Emboden (1979), Valdes (1983), and Valdes et al. (1987) have all correctly reported that the corollas of S. divinorum are pure white, while the calyx and flowering stem are violet blue.

    In the course of his pharmacological research, L.J. Valdes (1983) and Valdes et al. (1987) performed several experiments designed to help answer questions regarding the reproductive biology of S. divinorum. Of the 14 flowers he cross-pollinated by hand, four set seed, though the number of nutlets that reached maturity is unclear (the ovary of each flower consists of four mericarps). Valdes concluded that the species is self-sterile, though apparently no attempt was made to self-pollinate any flowers. Daylength experiments, carried out in order to explain the blooming requirements of S. divinorum, suggested that it is an obligate short-day plant, with plant height a minor factor in flower initiation. Still, the sporadic flowering of wild populations, the conditions that promote flower initiation, and the failure of the flowers to lead to fruit formation are aspects which remained unclear. These and other questions regarding coevolved pollinators and biological status are addressed below. Investigations of the author (Reisfield 1987) described here have involved visiting and collecting material from many populations in the field, a "stakeout" at a flowering population to observe pollinators, chromosome number determination, greenhouse flower induction experiments, artificial self- and cross-pollinations, pollen stainability studies, fluorescence microscopy of pollen tube growth through styles, and nectar analyses.