The giant trembles. It is the nickname of Pando, the largest organism in the world. Weighing more than six thousand tons, Pando is not a simple forest, it is a single organism. This colony of aspen trees located in Utah, in the United States, is in effect composed entirely of clones connected by a single root system.

If Pando (meaning “I lay” in latin), is spread over 43 hectares, it is thanks to its system of reproduction particular. In the very dry climate of Utah that does not allow that the seeds of this species germinate, the plant has to adapt. The forest is thus mainly formed thanks to new shoots of the same plant, which has germinated from a single seed, at a time when the climate was much more humid. The colony consists of over 47 000 ramifications genetically identical.

“Tree, forest”

But this single organism is in danger today, finds a study published on Wednesday 17 October in the scientific journal Plos One. A team of researchers from the University of Utah has conducted the first comprehensive assessment of the clone Pando. For this, she has gathered aerial photos from the past seven decades of the colony. And the results show a continuous degradation of this ” tree forest “.

According to these documents, the decline of the regeneration of the forest began about 35 years. While the older trees reach the end of their life cycle, the succession of young shoots takes over. “Walking in a forest, we always expect to find juvenile fish,” says Paul Rogers, professor of ecology and senior author of the study. But here, there are more young trees to replace the dead trees. “

the intrusion of the wildlife seems to be the main cause of the interruption of the cycle of the plant. Deer and elk are present in abundance in the region, are fond of the young shoots of the tree, and…