Senna (herb) facts for kids
|Golden Senna -Senna candolleana|
Senna (from Arabic sanā), the sennas, is a large genus of flowering plants in the legume family Fabaceae, and the subfamily Caesalpinioideae and the tribe Cassieae. This diverse genus is native throughout the tropics, with a small number of species in temperate regions. The number of species is estimated to be from about 260 to 350. The type species for the genus is Senna alexandrina. About 50 species of Senna are known in cultivation.
Senna includes herbs, shrubs, and trees. The leaves are pinnate with opposite paired leaflets. The inflorescences are racemes at the ends of branches or emerging from the leaf axils. The flower has five sepals and five usually yellow petals. There are ten straight stamens. The stamens may be different sizes, and some are staminodes. The fruit is a legume pod containing several seeds.
Senna species are pollinated by a variety of bees, especially large female bees. They rely on "buzz pollination" and some within that on "ricochet pollination", which is a secondary pollen presentation where the pollen is not deposited on the pollinator's body by direct contact with the anthers.
Historically, Egyptian senna was used as a laxative in the form of senna pods, or as herbal tea made from the leaves. Senna is considered to be a bowel stimulant on the myenteric plexus of the colon to induce peristaltic contractions and decrease water absorption from inside the colon, effects that would provide relief from constipation.
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Senna (herb) Facts for Kids. Kiddle Encyclopedia.