Heimia salicifolia

Slender willow-leaved Mesoamerican shrub used as a fermented infusion to produce a distinctive auditory shift — the world seems to grow quieter and slightly more golden, with sometimes pronounced changes in pitch perception.

Streamside shrub of montane and subtropical grasslands from the southwestern United States south to Argentina.

• Used in Mexican folk medicine and reportedly in some pre-Columbian divinatory contexts

The active alkaloids — vertine (cryogenine), lyfoline, and others — are quinolizidine derivatives with unusual auditory effects rarely seen in other plants.