Naro breeds tree species for dry lands

Terminalia schimperiana can grow anywhere in country. Photo | Lominda Afedraru

What you need to know:

  • Terminalia schimperiana is a broadleaved small tree that can reach up to 7–14 metres, variably deciduous in the dry season to semi-evergreen, depending on the climate.

Early this year the world commemorated the International Day of Forests, with the Food and Agriculture Organisation (FAO) joining Uganda to reiterate their commitment to restoring forests and degraded lands, as well as calling for action to reduce deforestation.

Background
The call for forest restoration and better management of the ecosystem was made during a high level national dialogue organised jointly by FAO, the European Union, Sweden and the Ministry of Water and Environment.

 According FAO, Uganda loses about 122,000 hectares of forests every year.
The experts noted that dealing with the challenge of loss of forests and biodiversity requires innovative approaches.

 During the 2014 Climate Change Summit, Uganda pledged to restore 2.5 million hectares of degraded forest land by 2030.
The government has also started a campaign to plant 40 million trees particularly indigenous species every year.

As such scientists at the National Agricultural Forestry Resources Research Institute (NaFORRI) have come on board with a research initiative where they are breeding exotic tree species that can grow in drylands of the country.

Planting trees in drylands
Citing the FAO 2019 report about forest cover in the drylands, the experts note that covering about 41 per cent of the earth’s land surface, more than 6 billion hectares, distributed among all continents, drylands are home to an estimated two billion people with about 90 per cent of them in developing countries.

“These ecosystems are vulnerable to water shortage, drought, desertification, land use and degradation and climate change impacts with dangerous ramifications for the food security, livelihood and wellbeing of their populations,” read part of the report.
 
Dr Isaac Kinyingi, programme leader forest conservation and management research at NaFORRI, explained that trees and forests in these lands help mitigate the challenges through provision of economic products. They also provide vital environmental services such as habitat for biodiversity, prevention of erosion and desertification and regulation of water and soil fertility.

To him, urgent action is needed to improve the management and restoration of drylands and this means a comprehensive understanding of the global and regional threats to drylands and their populations is required to pinpoint what interventions are needed and where.

Unfortunately, the monitoring of dry land ecosystems has not attracted as much attention as that of other ecosystems such as humid tropical forests.

Therefore, he says, for the case of Uganda his team been driving a research agenda where they are testing seven tree hybrid tree species in the cattle corridor areas.

The various tree species
The tree species which are now under trial sites at Nakasongola, Mbarara, Kazo Kiruhura and Nabilatuk among others include Melia volkensii Uganda species and Melia volkensii Kenya species.

They are a tree species endemic to the semi-arid areas of eastern Africa. Its natural range falls within areas which are characterised by dry bush land and wooded grassland, lying between 400 and 1600 metres above sea level. Recently, there has been increased awareness about its importance as a potential plantation species for timber production in Uganda.

Gmelina arborea Roxb originating from verbenaceae family. It is a fast growing tree frequently planted in dry land plantations to produce wood for light construction, crafts, decorative surfaces, pulp, fuel and charcoal.

The species is also planted in taungya (land initially cleared for crop growing) systems with short-rotation crops and as a shade tree for coffee and cacao. The third species is Terminalia schimperiana which is a broadleaved small tree species that can reach up to 14 metres, variably in semi- arid area depending on the climate.

It can be found in open forest habitats with more than 1300 mm of rainfall per year. When it is found in closed forest, it is typically part of the forest canopy.  Others are Eucalyptus hybrid GC550 and Eucalyptus GC596, which are resistant against pests such as termite attack which are common in dryland areas.

The other tree species under research by the scientists is Grevillea Robusta which is a deciduous tree shedding its leaves annually with a conical crown. It can grow 12 - 25 metres tall with exceptional specimens up to 40 metres and can be free of branches for up to 15 metres with an oval leafy crown.

Propagation
Dr Kiyingi explained that already some farmers are growing some of the tree species and his team has acquired cuttings from two specific farmers growing them in the central region for commercialisation.

The tree species can be grown from seed and propagated seedlings in nursery beds. Once it is raised into seedlings, the scientists identify the quality growing types which are then transferred in the trial fields. The spacing for planting is 3m by 3m.