Pernicious pea

Abrin is the poison in the seeds of rosary pea (Abrus precatorious). Its showy seeds are poisonous to humans – if the hard seed coat is broken. More than one person who grew up in here Florida has told me of accidentally swallowing rosary pea seeds, when trying to expel them from a “pea-shooter”. Its hard seed coat (outer covering) protects mammals from accidental ingestion. However, if the seed coat is broken, one rosary pea seed can kill a child.

A member of the ubiquitous pea (Fabacae) family, this climbing vine has alternate even-pinnate leaves and lavender ‘sweet-pea’ flowers. Prior the days of air conditioning, this delicate vine was planted on porches for shade and cooling. Above it is pictured overtaking a soft-leaved wild coffee (Psychotria sulzneri).

The hard-coated seeds of this Category #1 Invasive Pest Plant, unfortunately, last for decades in the seed bank. Reportedly, seeds of this species found submerged on the shipwrecked Atocha (1715) germinated.

Birds reportedly spread its seeds, and you can find it growing in the parking lot at the Oslo Riverfront Conservation Area, on the edges of moist hammock areas, and in dry, sandy scrub soils. Linda Chancellor (Class of 2010), though, sent a report of an incident in which more than fifty cedar waxwings died reportedly due to eating copious amounts of rosary pea seeds.

Other common names for this plant include crab’s eye, precatory pea, Indian licorice, and jequirity. Rosary pea refers to its use as rosary beads, and its seeds continue to be used in jewelry from the many tropical places to which this invasive pest plants has spread.

Its older stems are distinctively thickened …

For many years to come, volunteers will need to expend hours of effort to begin to get this invasive vine – with very long-lived seeds – under control.