Tagasaste, Fodder Shrub
Tree lucerne is a fast-growing, nitrogen-fixing shrub or small tree, originating in the Canary Islands.
Tree lucerne produces high yields of palatable, nutritious fodder as well as shade for livestock. It helps to control soil erosion and increases fertility. It produces nectar for bees and, if allowed to develop, will form thick branches which produce an intense heat when used as fuelwood.
- Elevation – 0-3000 m
- Rainfall – 350-1600 mm/year
- Soil Types – prefers sandy soil, but will grow other places
- Temperature Range – a range of 16-24°C is optimal; established trees can tolerate some frost (down to -6°C)
- Day Length Sensitivity – n/a
- Light – partial to full sun
Tagasaste can be grown as a single stemmed tree reaching a height of 7-8 m, but it is more commonly grown as a multi-stemmed shrub of 5-7 m. It produces pea-like white flowers in early spring. These distinguish it from other related species which produce yellow flowers and which are unpalatable. It is a good candidate for dry, cool areas such as occur in high-altitude parts of Ethiopia. The seeds are hard and must be scarified or treated with boiling water for no more than a minute to ensure quick germination. They should be planted with adequate fertilizer to ensure deep rooting. The seedlings transplant very well. The plants are usually grown in rows which can be interplanted with other crops as they will provide shelter from cold and wind. They must be protected from grazing animals, including rabbits, until they are mature. With a deep root system (penetrating up to 10 m in sand), it is drought resistant and a good scavenger of soil nutrients. It needs a soil pH of 5.0-7.0.
Harvesting and Seed Production
Seed pods turn black when ripe and contain 8-12 black seeds.
Pests and Diseases
Tagasaste is free of pests and there is no evidence of viral infection. Slugs, cutworms, and grasshoppers eat emerging seedlings but can be controlled with one application of insecticide. Mature shrubs are the last to be attacked by grasshoppers but even then, make a rapid recovery.
Cooking and Nutrition
The leaves contain 17% crude protein and 16% crude fiber. They do not contain toxic substances.