This archive report was first published on 23 May 2020.
Published on May 23, 2020, by TIM WANYONYI, a renowned author.
Sesbania sesban, also known as the hummingbird tree, is native to Asian countries such as India, Sri Lanka, Malaysia, Indonesia, and the Philippines. However, it has also spread widely across Africa, from Senegal in the west to Somalia, Egypt, and South Africa.
Its adaptability to various ecological zones in Kenya, ranging from altitudes of 350m to 1,900m above sea level and annual rainfalls of between 400mm and more than 1,400mm, makes it a valuable resource for farmers.
Before discovering the waterlogging tolerance of Acacia xanthophloea, Sesbania sesban was the only tree that thrived on the swampy part of my farm in Soy.
According to the Kenya Forestry Research Institute's publication, 'A Guide to Tree Planting in Kenya,' any tree species selected for planting must fulfill specific objectives, including soil and water conservation, improvement of soil fertility, animal fodder, shade, and saleable products.
Sesbania sesban ticks many of these boxes, although its potential has not been fully exploited in Kenya, unlike in its native Asian lands.
The tree improves soils by fixing nitrogen and forming green manure. Its leaves are also used as a cover for crops such as turmeric, ginger, and vines.
Studies have shown that one-year fallow with Sesbania sesban can increase maize yields from two to four tonnes per hectare without the application of nitrogen fertilizer.
However, the tree harbors root-knot nematodes, which should be avoided in combination with crops sensitive to nematodes like bananas and potatoes.
The nutritional benefits of Sesbania sesban make it an essential component of any diet, particularly in Asia, where it is used in curries, soups, and as a vegetable.
Its seeds are high in protein (33.7%), and the foliage is used as fodder for cattle, goats, and sheep.
A study published in Livestock Science attests to the suitability of Sesbania sesban as a fodder tree in Ethiopian livestock farming systems.
Its various parts, including bark, roots, leaves, gum, and flowers, are used in traditional medicine to treat illnesses such as rheumatism, leprosy, gout, and liver disorders.
Propagation is by direct sowing at site or wilding, and seeds cost Sh1,500 per kilogram at Kenya Forest Research Institute seed shops.
