the last 50 years the whole of the area around Budongo Forest has come to be inhabited
by people. We shall look at the details of the human population in Chapter 10, but we
should note that today, as never before, any discussion or description of Budongo Forest
needs to consider the people living around it. They are chipping away at its borders,
turning forest edge into cropland. They are putting snares and traps on their fields to
catch baboons, forest pigs and porcupines that come to eat their crops. They are going
into the forest to cut poles for their houses and collect medicinal plants. They are setting
snares in the forest to catch duikers for their cooking pots (and in the course of doing so
they are inadvertently catching chimpanzees which suffer serious limb injuries as a
result). And during the last century, with ever-increasing speed, they have felled and
sold the fine mahogany trees that made the Budongo Forest estate the most valuable in
Uganda, so that today its commercial value is small and will take half a century at the
very least, and perhaps much longer, to recover its former glory (Reynolds 1993).
Dynamics of Budongo Forest
Two early descriptions of Budongo Forest are those by Harris (1934) and Brasnett
(1946). Harris was the first to discuss the idea that the mahoganies and other species of
valuable timber trees that occurred in Budongo might be subject to eventual exclusion
by a more powerful species,Cynometra alexandri, or the ironwood tree. This idea pro-
vided the basis for a major silvicultural programme run by the then British-led Uganda
Forest Department in later years. Brasnett concurred. He described Budongo as a relat-
ively young forest, possibly some 300–500 years old. He noted a number of features of
the forest, in particular that it contains both young (Colonizing), intermediate (Mixed
species) and mature (Climax) forest.
This introduces the idea of a succession of stages in the life of a forest. Succession is
a fundamental idea in the understanding of how forests grow. Initially, when grassland or
bush is being taken over by trees, whether due to a gradual sustained increase in rainfall
from one decade to the next, or to the disappearance of pastoralists, the trees that manage
to flourish are pioneer species, that is species whose seeds, seedlings and saplings thrive
in conditions of bright hot sunshine such as Acanthusspp. Once one or more such
species have established themselves and grown to maturity, they inevitably change the
habitat, primarily in two ways. First, the colonizing species remove some of the moisture
and nutrients from the soil. And second they provide a degree of shade which prevents
evaporation to some extent. In such conditions, other species that are better adapted to
these new conditions can gain an advantage. If birds or other seed dispersers bring in
seeds of species that use less moisture from the soil, or have deeper roots, or can use
other soil nutrients, and in particular if the newly arrived species can flourish in a degree
of shade, i.e. in slightly cooler conditions with less solar radiation reaching the leaves of
the growing seedlings and saplings, then such species will out-perform the colonizers
and the next successional stage of the forest will be reached. This process will be con-
tinued again and again during the history of the forest. Finally a climax phase may be
reached in which a particular monodominant species (i.e. species that can exclude all
12 The Budongo Forest