Different savannas support different grasses due to disparities in rainfall and soil conditions. Because the savanna supports such a large number of species competing for living space, usually only one or a few kinds of grass are more successful than the others in a particular area. Deciduous trees and shrubs are scattered across the open landscape. Frequent fires and large grazing mammals kill seedlings, thus keeping the density of trees and shrubs low. Savanna has both a dry and a rainy season.
Seasonal fires play a vital role in the savanna's biodiversity.
In October, a series of violent thunderstorms, followed by a strong drying wind, signals the beginning of the dry season. Fire is prevalent around January, at the height of the dry season. Fires in savannas are often caused by poachers who want to clear away dead grass to make it easier to see their prey. The fires do not devastate the community. Most of the animals killed by the fires are insects with short life spans.