Abrus precatorius aka Rosarypea

Abrus precatorius, or rosary pea, is in the bean family. It is native to the tropical and subtropical Old World. Its range includes the north and east of Australia. It grows in tropical lands with a dry season. It lives in lowland forests, thickets, and hedges. This climber lives for years. It winds around shrubs and trees for support. Sources say it can keep its leaves or shed them.

One source gives a height of about 11.5 feet [3.5 metres]. Its stems can grow 20 feet [6 metres] long. Some reach nearly 30 feet [9 metres]. Many stems grow from the base and trail across the ground. A deep main root makes plants hard to remove once established. The green leaves are pinnate, with leaflets paired along a stalk. Each leaf has five to fifteen pairs. Each leaflet is oval or oblong, with smooth edges. The leaflets hang down at night and rise with daylight.

Small flowers look like pea flowers. They grow in groups where leaves meet the stems. Their colours range from white to pink and violet. Flat, oblong pods curl back as they open. Each pod holds three to eight hard, glossy seeds. Most of each seed is scarlet, with a black end. These seeds give the plant its crab's eyes name. Birds eat the fruits and spread the seeds without apparent harm.

The plant prefers rich sandy loam that drains well. It grows in full sun or partial shade. It can also cope with salt. People have grown it for its looks and medicinal use. Its bright seeds make beads for necklaces and rosaries. People have also used them as small weighing units. Thin stems serve as short-term ties. The bark makes rough cord. But its fast growth causes serious problems outside its native range. It invades ground both with and without disturbance. It can spread fast after fires and become a pasture weed. North Carolina State reports that Florida lists it as a noxious weed. The same source reports limits on growing it.

All parts contain poisons, but the seeds pose the greatest risk. Abrin can kill people and animals through poisoning. Broken seed coats expose pets to the seed's toxins. Signs include vomiting, diarrhoea, tremors, fever, and shock. People may show symptoms hours or days later. Records list cooked young leaves and seeds as famine foods. They also note the use of roots in place of liquorice. These past uses do not prove safety for home use. The roots contain toxic compounds. Sources warn against their use.