Research and Conservation in Southern Sonora, Mexico

Tabebuia impetiginosa (amapa morada, amapa rosa)
Tabebuia chrysantha (amapa amarilla)

Tabebuia impetiginosa is a widespread tree of the New World tropics, extending from southern Sonora to Argentina. In Sonora it grows 15 to 50 feet tall with a straight trunk that is usually unbranched to about half the tree's height. The compound leaves are present only during the summer rainy season. In contrast to the flowering phenology farther south, in Sonora flowering must be triggered first by sufficient drying to cause leaf drop, then by a pulse of winter rain. If autumn is wet enough to keep the trees leafy or if the winter is rainless, flowering is poor or may fail altogether. Amapa flowers for about two weeks per flush, and may have two or more flushes each year. A flowering event lasts about two weeks; it usually peaks in the first half of February but can occur from October to March. This is one of the showiest trees in the tropical deciduous forest of Sonora.

Photo: S.A. Meyer	Photo: T.R. Van Devender
Amapas are often left standing in pastures because they are strictly protected by law. Photo: Mark Dimmitt	Photo: S.A. Meyer

Brazilian members of this genus are known as ipe and provide very high quality hardwoods. Amapa is also a superior wood. The tall straight trunks were commonly used as roof beams in colonial houses in Alamos, which were covered with 18 inches of mud for insulation. The wood is not only strong enough to bear the weight, it lasts over 100 years because it is resistant to fungus and termites. The tree became severely depleted from overharvesting; after several decades of strict protection it has made a dramatic recovery.

Tabebuia impetiginosa is a common tree in the forest around Alamos. Photos: S.A. Meyer

Amapas stand out spectacularly when in flower. The rest of the year they are inconspicuous members of the forest. Photo: George M. Ferguson

T. chrysantha is most commonly called amapa amarilla in Sonora, but it is also known there as roble and verdecillo. The tree is similar in stature to T. impetiginosa. It is much less common in Sonora than the pink-flowering species. The bright yellow flowers are more ephemeral; the spectacular display usually lasts only a week. It most commonly blooms in March. Amapa amarilla ranges from southern Sonora to Venezuela.

A mediocre flowering flush. Photo: George M. Ferguson

Photo: Mark Dimmitt

This is an unusually dense grove of T. chrysantha, but it's a sparse flowering. Photo: Mark Dimmitt