Rhomboid Mercury (Acalypha rhomboidea) vs. Deam's Mercury (Acalypha deamii)
Updated June 25th, 2024These two species look similar, especially early in the growing season. They can be distinguished by the number of seeds per bract, and they have subtle but mostly overlapping differences in leaf margins, leaf dimensions, bract dimensions, and growth habit. A. rhomboidea is common and abundant, has a much wider range, and ranges into sunnier and drier habitats, prefers more fertile, loamy soils, and is more tolerant of clay soil and competition from other plants. A. deamii is uncommon to rare, has a much smaller range, is restricted to moist, open forests, prefers more sandy or gravely soils, and is less tolerant of sun, dry conditions, and competition, but is more tolerant of shade.