EPOW - Ecology Picture of the Week

Explanation:    No, this isn't a sperm whale standing on its tail.  It is the immense buttress of an old-growth tropical tree growing in the heart of the Congo River Basin.

We are in the remote equatorial African village of Bobangi, along the shores of the Ubangi River in Equateur Province of the Democratic Republic of the Congo.  Deep in the heart of the swamp forests here grow trees so immense they dwarf their human observers.  Such trees likely will not be cut down, at least by local villagers who fell trees by hand using ax and then cut the logs into boards by hand using long saws ... these huge trees are too large, and the buttresses too extensive, to facilitate hand-cutting.  Also, the tree boles (trunks) are too fluted and twisted to yield lumber of any quality or to be used for carving dugout canoes ("pirogues") so common in the area.  

Tropical trees often have wide buttresses at the base, to help stabilize the trunk in thin or saturated soils.  

This tree has been called a "monkey's nightmare."  It is unclimbable because it is self-pruning and in older specimens branches do not appear for a very long ways off the ground.   The tree spreads throughout the forest by fruit-eating birds such as hornbills.  It regenerates in logged forests but also in canopy gaps in native forests.  

Trees in this part of the Congo often go by several names -- a general common name and sometimes also a more local common  name, a commercial name, and a scientific name.  The general common name (in Lingala) for this tree is bouma, its local dialect name (in Mongo) is bosongu, its local commercial name is musisi, and its scientific name (in Latin) is Maesopsis eminii.  Further, in southern Democratic Republic of Congo, it is called mutsambi tsambi in the Kiyombe language, and in the north it is known as ofambu in the Turumbu language.  

And in English it is called the umbrella-tree.  

By any name, it is a giant of the Congo rainforests and one of the largest tropical trees this ecologist has seen.