Definition of vegetation

Refers to all forms of plant life growing in an area. As a community of plants like trees, scrubs, herbs, woodland and grasses that cover an area and give it a distinct character.

Vegetation is the living mantle of plants (flora) which covers much of the land surface forming an important aspect of the physical environment.

Vegetation is very important because the natural vegetation provides a good base for rational use of land for economic benefit.

The natural vegetation of East Africa has been adversely affected by human activities that today; East Africa has a very small percentage of her original vegetation cover left.

Vegetation communities in East Africa

The vegetation of East Africa covers the full range between rainfall forest and semi desert vegetation, and from an equatorial shore line to the highest peaks i.e. Kibo at 5898metres on Mount Kilimanjaro) Plant communities are classified as follow;

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Tropical Rain Forests/ Equatorial Forests

In Uganda

They are found around the shores of lake Victoria, lake Victoria islands: Ssese, Bukasa, Bubeke, Bugaia, Lulamba, Ngamba, Buyorii, Bujumba, Funve in Kalangala district; Damba, Kome, Lwaji, Buvuma, in Mukono district; Mabira, Mpanga in central region; Budongo (Masindi), Bugoma (Hoima), Kibale (Kabalore), Bwindi (Kanungu), Kashoha-Kitomi(Bushenyi), Maramagambo (Bushenyi), Echuya, Kalinzu, Ibambaro, Kasato, Muhangi, Itwara, Wambabya in western Uganda; Zoka, Wiceri in Northern Uganda;

In Kenya

They are found in Kisii –Kakamega region, mau, matheus, Loroghi, Molo, Maraket, Chepalungu, and Marsabit etc.

In Tanzania

They are found in Bukoba region, Songea, Morogoro and Tanga

Equatorial forest (vegetation) is characterized by:

  • It comprises of a multitude of ever green trees that yield tropical hard woods like Mahogany, Ebony, green heart, Cabinet wood, Dye wood, Mvule, Musizi, Elgon olive.
  • There are climbing plants like the Lianas or Rattan and Epiphytic, and Parastic plant that live on other plants. There is also a wide variety of Creepers, ferns, Orchids, Lalang and herbaceous plants.
  • Forests form three layers of canopies.
  • The trees are heterogeneous in nature. They are not found in pure stands of a single species. (Have mixed species).
  • The trees are tall of about 45 meters, with slender trunks which are straight.
  • The trees have evergreen broad leaves throughout the year.
  • There is little or no under growth because of the thick canopy of foliage.
  • The trees have huge buttress roots.
  • The trees are umbrella shaped
  • Economic Value
  • Development of the tourism industry (fauna and flora) – National parks like Bwindi Impenetrable forest reserves.
  • Growing of perennial and annual crops (tropical and temperate crops) like coffee Banana, Sugarcane.
  • Lumbering / exploitation of forest resources on a small scale lumbering, charcoal burning and gathering of firewood in Mukono
  • Collection of fruits, nuts, roots SAVANNAH VEGETATION Savannah refers to wide range of plant communities ranging from unbroken treeless grassland to woodlands in which trees and shrubs form an almost continuous cover. Savanna Vegetation is categorized into two groups:
  • Savanna grassland: It is covers the biggest part of Uganda mainly in the central region. It covers the districts of Luwero, Kamuli, Iganga, Muyuge, Mubende, Mityana, Hoima, Apac, Lira, Kasese, Sembabule, Masaka, Mbarara and Kiruhura. In Tanzania, it covers Northern Tanzania, Arusha, Shinyanga, Tabora, Kigoma provinces. In Kenya, it covers the eastern province and some parts of the coast province
  • Dry savanna wood land: This area covers parts of Kitodo, Soroti, Kitgum, Kumi, Hoima, Moyo, Nebbi, Masindi, Nakasongola and Kabarole districts in Uganda. In Tanzania, it mostly covers the southern and western Tanzania in Lindi, Dodoma, Ruvuma, Mbeya, Mtwara, Sindiga, Kigoma, Rukwa and Iringa. Savanna vegetation is characterized by;
  • The savanna vegetation varies with the amount of rainfall from wood land with long grass, through acacia woodland which has short grass and scattered trees, to open, short grasslands with thorny bushes in the semi- desert areas.
  • Trees and plants have adapted themselves to the savanna climate rhythm of long winter drought and short summer rain both trees and plants are therefore, deciduous in nature, shedding their leaves in the cool dry season to prevent excessive loss of water through transpiration and lying dominant during the long drought.
  • They have long roots (like the acacia trees) to search for ground water or broad trunks (like bottle and baobabs trees) to store up excessive water.
  • Trees are mostly hard gnarled, thorny and may exude gum.
  • Many trees are umbrella- shaped to shield their roots from the scorching heat and to expose only a narrow edge to strong trade winds that blow all the year round.
  • The grass is tall and coarse, growing 2 to 4 metres (6-12 feet) high. The elephant grass may attain a height of 15 metres.
  • The grass which grows in compact tuffs has long roots which reach deep down in search of water.  The appearance of the savanna vegetation changes with the season. It appears green and fresh in the rainy season but turns yellowish-brown and parched with the ensuring dry season.
Economic Value

It has led to development of the tourism industry. Savannah grassland in particular is the home of wild animals like Lions, Uganda Kobs, Giraffes and Zebra.  Livestock farming i.e. Nomadic pastoralism and Beef cattle ranching  Growing of Perennial and annual crops like Sorghum, Millet, Maize, cassava, sweet

Api- culture (Bee-keeping).

Charcoal burning and gathering of firewood from savanna woodlands SEMI – DESERT VEGETATION (DECIDUOUS BUSHLAND AND THICKET/ SCRUB VEGETATION) It covers the rest of North Eastern Uganda in the districts of Kotido, Moroto, Abin Kaabong and Nakapiripirit. In Kenya, the semi desert vegetation is found in the Northern rift valley province, North Eastern Province, part of coast province and part of the eastern province. In Tanzania, this type of vegetation is found in Dodoma, Tanga, Manyara and Sangida. Semi-desert vegetation is characterized by;

Most of the scrubs have long roots and are well spaced out to gather moisture and search for ground water.

Plants have a few or no leaves and the foliage is waxy, leathery, hairy or needle-shaped to reduce the loss of water through transpiration.

The seeds of many species of grasses and herbs have thick, tough skins to protect them while they lie dormant. They germinate at once when their seeds are moistened by the next rain.

Some of the plants are entirely leafless, with pricks or thorns.

The predominant vegetation in semi-desert area is Xerophytic or drought-resistant scrub. This includes the bulbous cacti thorny bushes, long-rooted wiry grasses and scattered dwarf acaciaEconomic Value

It has led to the development of the Tourism Industry i.e. Kidepo Valley National Park.

Nomadic Pastoralism by Karamojong, Matheniko, Masai and Galla

Growing of drought resistant crops like millet, Sorghum in Abim.