8.  SOME AGROFORESTRY PRACTICES IN KENYA                   

8.13 Trees in rangeland

Spatial arrangement

Scattered trees in rangeland are beneficial in many ways, e.g. providing shade for livestock and herdsmen, and fodder and wood. Normally such trees are scattered at random and there is no need to be particular regarding any regular spatial arrangement.

Areas where the practice is relevant

This practice is relevant for all rangelands.

Establishment and spacing

Any propagation method may be applicable, but use of seedlings can be recommended since it is essential to minimize the period during which protection is needed. Natural regeneration should be considered before tree planting is recommended, but both methods can be used at the same time.

If trees are to be planted, they should not be too dense since this may interfere with grass production. A spacing of 10 m x 10 m has been recommended for small trees and 15 m x 15 m for large trees (Mbote and Fahlström, 1992).

Trees can be planted either scattered in the rangeland or in other arrangements, e.g. in lines.

Figure 8.16 Trees in range land

If there are too few trees on sloping land they may contribute to land degradation through intensive trampling by cattle seeking shade. If there are signs of this, it is a clear indication that more trees need to be established.

Management aspects

Protection of the seedlings is required in the initial stages. In communal grazing areas this will require the full support of all people using the area.

Benefits

Improved supply of fodder and environmental benefits, e.g. shade. Certain species may suppress the growth of grass and such species should, of course, be avoided. Another risk is that drought or overgrazing may kill off most of the trees that the people have spent a lot of time and money planting and then they will lose interest in trying to establish trees again.

Examples of species

Acacia brevispica, Acacia elatior, Acacia gerrardii, Acacia mellifera, Acacia nilotica, Acacia polyacantha, Acacia Senegal, Acacia seyal, Acacia tortilis, Annona senegalensis, Balanites spp., Bauhinia spp., Berchemia discolor, Boscia coriacea, Cadaba farinosa, Calliandra calothyrsus, Combretum molle, Cordia spp., Dicrostachys cinerea, Diospyros scabra, Dobera glabra, Gliricidia sepium, Grewia spp., Lannea schweinfurthii, Maerua subcordata, Piliostigma thonningii, Salvadora persica, Terminalia brownii, Ziziphus spp.