Crotalaria pallida aka Moreton Island Rattlepod

Crotalaria pallida has the common name smooth rattlebox. It is part of Fabaceae, the pea family. It comes from tropical Africa. It has spread across many tropical regions. It now grows wild in those places. It grows by rivers and lakes, in grassland and woods. It also grows on waste ground and sandy sites. Records from southern China list grassland and sandy ground.

This herb lives for more than two years. It grows upright and has many branches. It can reach about 6.6 feet [2 metres] tall. Its stems turn woody as they age. The source gives no width for a full-grown plant. Nor does it describe the leaves in detail. It shows flowers and seedpods, but gives no bloom season. Growers have long used it to cover ground. They also use it as green manure. Farms still grow it in the southeastern United States. Pests and diseases have cut its use in Asia.

This plant suits tropical and subtropical climates, including warm lowlands. Growers have raised it at heights of 5,906 feet [1,800 metres]. Known sites have mean yearly temperatures of 16–26°C. Yearly rainfall ranges from 850 to more than 3,000 millimetres. It grows in some fairly dry places, too. Give it full sun, as shade limits its growth. It grows in many soils and suits sandy ground. Some peat soils under coarse grass do not suit it. Trials in Thailand show it can grow in salty conditions. Plants can escape from farms and gardens. They can take root and grow beyond those sites.

People eat the flowers as a vegetable. They also make food and drinks from the seeds. One seed food, dage, goes through a fermentation process. People boil the seeds for a long time first. They then leave them to ferment in banana leaves. People also roast seeds to use in place of coffee. Some chew the roots with betel nut. These old uses do not prove the foods are safe. The seeds contain pyrrolizidine alkaloids, which can harm the liver. Harm from repeated use may take a long time to appear. Fresh leaves also contain an alkaloid that poisons goats.

In folk medicine, people use this plant to treat fever. They also use it for problems with passing urine. Other uses treat skin problems, wounds, gut worms, and swollen joints. These records do not prove such treatments work or are safe. Researchers use a lectin from the plant in cell studies, too. Growers raise new plants from seed. Soaking seeds in warm water before sowing can speed sprouting.