Afforestation and soil reclamation
In India, Senna siamea is planted in degraded and dry areas for rehabilitation of forests, and it holds promise for reclamation of mined areas (aluminium mine tailings)(Orwa et al., 2009). It has been used in a afforestation program aiming at fixing the fly ash from a thermal power station in India (Lal, 1996). In Northern Ghana, where the disappearance of tropical forest is alarming, Siamese senna had higher growth rate than the neem tree (Azadirachta indica) and was recommended for afforestation (Damian et al., 2014).
Erosion control and soil improver
Siamese senna planted in hedgerows increased topsoil infiltration, reduced runoff and prevented soil erosion. A well-grown tree can yield 500 kg/year of fresh leaves that can be used as green manure. Senna siamea forms ecto-mycorrhizae and provides very useful mulch, especially in alley-cropping systems (Orwa et al., 2009).
Boundary or barrier or support, shade and shelter
Siamese senna trees planted in hedgerows provide live fence around food crops. It can be grown as a shade tree along roads and in cocoa, coffee and tea plantations. It is a useful windbreak and shelterbelt (Orwa et al., 2009).
Invasiveness
Due to its fast growth and prolific seed production, Senna siamea is considered to be invasive in Australia (especially the Cape York Peninsula, Queensland), Mexico, the Caribbean (Dominican Republic and Puerto Rico), the Pacific (Fiji and French Polynesia) and Africa, and may pose a significant risk of invasion in other countries where it is already present and cultivated (CABI, 2018).