Bolivia

Cerro de Comanche

It has been thought that the largest bromeliad, Puya raimondii, was an endangered species due to human activities, but recent inventories showed that there are still many colonies of them in Bolivia and Peru. One of the most accessible is a three hour drive from Bolivia's capital, partly on dirt road.
At the hamlet of Comanche along the railway direction Chile there is a granite quarry in a rock on which the big Puyas - to 10 m high when in flower - are standing. During my visit none were seen flowering but there were many young plants; it is said that flowering happens to the plant only after 100 years. Propagation of the plant is only by seed, no shoots are formed.
  

In Bolivia there are 19 known colonies ('rodales'), most of then situated in the Cochabamba-department, with an estimated total of 20 to 25 thousand plants. In Peru there are about 25, ranging from Ancash in middle Peru to Puno in the south ; numbers per rodal vary from several hundred to 5000 specimens, however there is a very large one with 400,000 plants in the department of Ayacucho that accounts for about 90 % of all Puya raimondii's in Bolivia and Peru together.
The photos below were taken at the Pampacorral rodal at Lares, 60 km north of Cuzco in Peru, a two hour drive on a winding road in the mountains. Again no flowering plants were witnessed, years may pass before such an event happens and if so it is often a synchronized happening, meaning there are many in flower at the same time.