Surviving witnesses?

The extremely compact growth of Azorella compacta (llareta) reduces the loss of heat and water. It allows the plants to survive the harsh conditions prevailing in the puna environments of northern Chile, at an elevation of 4500 m. The dormant, glacierized Volcán Parinacota (6348 m) appears in the left background. Even though the last eruption of this stratovolcano occurred at least 1400 years ago, the llaretas shown in the picture might have witnessed this event: these plants grow slowly and possibly reach ages above 3000 years.