Sickle senna is closely related to Senna obtusifolia, but the latter can be recognized by its longer pedicels[]. The distinction between S. obtusifolia, S. occidentalis and S. tora is not always properly made; names have often been misapplied and vernacular names may apply to all of them[]. The presence of S. tora in Africa is doubtful and references to it probably concern S. obtusifolia[].

Common Name: Sickle Senna

General Information

Senna tora is an annual to perennial plant with stems that can become more or less woody; it can grow up to 2 metres tall[, ].
The plant is gathered from the wild for local use as a food and medicine. It is sometimes cultivated for its seeds, which are used as a mordant[, ].

Known Hazards

None known

Botanical References

, ,

Range

Tropical America. Naturalized in many other areas of the tropics.

Habitat

Mostly in waste ground, often in dry to wet thickets, or as a weed in cultivated ground, at elevations up to 1,000 metres in Guatemala[]. Mountain slopes, waste lands, river bank sands in southern China[].

Properties

Weed Potential	Yes
Edibility Rating
Medicinal Rating
Other Uses Rating
Habit	Annual/Perennial
Height	1.00 m
Pollinators	Insects
Self-fertile	Yes
Cultivation Status	Cultivated, Wild

Cultivation Details

Plants succeed in the tropics and subtropics[].
Prefers a deep, well-drained, moderately fertile sandy loam and a position in full sun[].
Originally native to the tropical Americas, this plant has escaped from cultivation and become naturalized in many other areas in the tropics.
The plant has a strong, unpleasant smell[].
The plant is an alternative host of Alternaria cassiae, which affects crops such as cowpea (Vigna unguiculata) and several Solanum species[].
There are conflicting reports on whether or not this tree has a symbiotic relationship with certain soil bacteria, so it is unclear as to whether this tree fixes atmospheric nitrogen[].

Edible Uses

Seeds - cooked or roasted in the pods[]. They are eaten as a side-dish with rice[].
The roasted seeds are a coffee substitute[, , ].

Young, tender leaves and shoots - cooked[, ]. They are steamed as a potherb, or cooked and eaten with rice[]. They contain about 6% protein[].


The following uses are for the closely related Senna obtusifolia, and probably also apply here.

The powdered and fermented leaves are used as a condiment[].

The leaves are used to make a tea-like infusion[].

The seeds are occasionally dried and ground into a powder, which is cooked and eaten as a staple food in moderate amounts[]. As the seeds are reputedly poisonous, cooking or roasting is deemed necessary to make them safe to eat[].
The seeds contain commercially interesting levels of gums[]. In India they are collected from wild plants for the industrial extraction of gums (galactomannans) for the food industry[].

Medicinal

The seeds are diuretic, laxative and purgative[, ]. The raw seeds are utilized as a laxative, in a dose of
10 to 15g per day. The torrefied seeds are effective in the treatment of insomnia, headache, constipation, oliguria. cough, ophthalmia, dacryoliths, amblyopia, ocular congestion and hypertension. The daily dose is 5 to 10g in the form of a decoction, powder or pills[].
The mature fruit is usually collected at the end of the growing season. The seeds are separated from the dried fruit and
usually roasted before use[].

The leaves are purgative[]. They are used in the treatment of ringworm and skin diseases[].
The alcoholic or vinegar maceration of the pounded fresh leaves is used externally to treat eczema and dermatomycosis[].


The following uses are for the closely related Senna obtusifolia, and probably also apply here.

The leaves are anthelmintic, laxative and poultice[]. They are used to rid the body of parasites and as a treatment against vomiting and stomach-ache[].
Externally, they are used to treat skin infections, sores, ulcers and insect bites[]. A decoction of the leaves is used to treat eye complaints[].
The laxative properties of Senna species are attributed to anthraquinones[].

The roots are used as a laxative and anthelmintic[].

The seeds are eaten, combined with a leaf decoction, to treat conjunctivitis[].

Other Uses

The seeds are used as a mordant when dyeing cloth blue[, ].


The following uses are for the closely related Senna obtusifolia, and probably also apply here.

The seeds, the macerated leaves and the roots provide black, blue, yellow and orange dyes[].
A yellow phenolic pigment, cassiaxanthone, has been isolated from the roots of Senna species[].

Myrothecium verrucaria, a fungus isolated from sicklepod, is used for control of nematodes in food crops and ornamental plants and is widely tested as a herbicide against weeds like water hyacinth (Eichhornia crassipes), Chenopodium album and Senna obtusifolia itself[]. Strains of Fusarium oxysporum and Alternaria cassiae were similarly obtained and showed considerable control of Senna species if applied at the pre-emergence stage[].

The stems are used to make mats and fences[].

Propagation

Seed - scarify and then pre-soak the seed for 2 - 3 hours in warm water before sowing it from early spring to early summer in a warm greenhouse[]. The seed usually germinates in 1 - 12 weeks at 23°c[]. Prick out the seedlings into individual pots once they are large enough to handle and grow them on in the greenhouse. Do not plant them out until the following spring[].
Division as growth commences in spring[].
Cuttings of moderately ripe wood, July in a frame[].