Tropical Africa is defined as the area situated between the Tropics of Cancer and Capricorn--essentially the middle part of the country. Tropical trees are cauliflory, which means the flowers and fruits grow directly from the trunk, allowing for easier pollination. This is essential, because the climate in tropical Africa is challenging; it ranges from humid to dry and encompasses both rainforest and semidesert, according to the Food and Agriculture Organization of the United Nations.
The robusta coffee tree reaches a height of 33 feet, according to "The Illustrated Encyclopedia of Trees of the World." The beans of this species provide for a quarter of all traded coffee, mostly espresso and instant coffee. The tree itself is highly disease resistant and is tolerant of poor growing conditions. A breeding program has been started to introduce the robusta's disease resistance to other coffee trees. The oval leaves of the tree are 8 inches long, and the white flowers bloom in clusters on the branches. The fruit takes 10 months to ripen and also forms in clusters on the branches.
The baobob tree is a recognizable part of the tropical African landscape. It ranges in height from 33 to 80 feet and can live to 100 years. As the tree ages, the trunk becomes swollen and eventually hollow. It can hold up to 2,000 pints of water, which can be tapped to drink, according to "Trees," by Colin Ridsdale. The smooth, gray-brown bark has a slight purple hue and the green leaves are divided between five and nine oblong leaflets. The baobob's flowers open at night and are pollinated by bats.
The kapok is a fast growing tree that can grow to a height of 230 feet; its pale gray bark is covered by thick spines when the tree is young. The leaves are 20 inches in width and vary from five to seven oval leaflets. The fibers on the hairs of the seeds are used for mattresses, pillows and refrigerator insulation, according to "Trees: A Visual Guide," by Tony Rodd and Jennifer Stackhouse. The pink and white flowers are bell-shaped and bloom during the dry season.