The dry montane forest of the Tuichi valley contains the highest species diversity in comparison to other dry forests in the Tropical Andes. It covers approximately 1,200 km2, of which 700 km2 are in an excellent conservation state, and is probably the largest patch of dry forest in the Tropical Andes.

The flora is similar to the Chiquitano forests of eastern Bolivia, the Andean foothill forest of the Tucuman-Bolivian region, and extensive dry montane forests of Bolivia and Argentina, with characteristic bromeliad, cactus and palm species.

These forests contain significant endemism and a high proportion of species from the Pleistocene, a geological period that lasted more than 2.5 million years and concluded 11,000 years ago. These biogeographic characteristics combined with their extension and conservation status, mean that the dry montane forests of the Tuichi are unique