The world’s largest single organism may soon fracture into smaller pieces.
According to a study published in the journal Conservation Science and Practice, this huge forest organism, known as ‘Pando’, may be on the verge of breaking apart due to ‘chronic herbivory’ or overfeeding by the animals.
Although it may look like a normal aspen forest in Utah, this 100-acre structure is actually the same organism. Pando is thought to have a dry mass of around 13 million pounds and is made up of genetically identical trees that share a gargantuan root system. It is thought to be up to 14,000 years old.
Plants can create genetically identical clones via suckers or basal shoots. These offshoots allow the plant to establish an identical version of itself in another location, growing into the soil and eventually joining the root systems. This “vegetative dispersal” is a form of asexual reproduction and is seen in a variety of other plants including Canada thistle, cherry, apple, hazelnut, tree of heaven, and Asimina triloba.
According to the article, written by Paul C. Rogers, assistant professor of ecology at Quinney College of Natural Resources and director of the Western Aspen Alliance, deer and cattle threatened Pando by eating new growth, limiting the longevity of the plant. structure: as old trees die, there are fewer young shrubs to replace them.
“The results show that the genetically uniform Pando is ‘breaking apart’ due to herbivory and fencing,” Rodgers wrote in the paper. “This iconic aspen clone has experienced persistent browsing over the past few decades by mule deer (Odocoileus hemionus Raf.) and cattle (Bos taurus L.) so that it dies slowly; a once dense canopy thins out as vegetative offspring (regenerating suckers) fail to mature.”
Previous attempts to prevent Pando’s decline, such as erecting fences to prevent herbivores from eating the new trees, have only exacerbated the problem, possibly separating the organism into fractured zones.
“Fences have been erected to mitigate herbivores at Pando, but such visual and ecological intrusions potentially bring additional problems, such as creating aesthetic disturbances and new floristic pathways in this natural wonder,” Rodgers said.
“Fencing to limit herbivory is a logical first step after decades of failed recruitment, though the barriers seem to have unintended consequences, potentially sectioning Pando into divergent ecological zones rather than encouraging a single resilient forest.”
Additionally, only about 16% of the body is adequately fenced to keep herbivorous animals out, with more than a third of Pando’s fences having fallen into disrepair and more than half of the structure having no no fence, according to Phys.org. These different impacts in various areas also serve to fragment the forest.
The media attention towards Pando and its decline has also further threatened the organism: “Current shipping pressure, alongside increasing human traffic, predicts a bleak future for Pando,” Rodgers wrote in the newspaper.
Current short-term strategies to restore Pando also include culling herbivores or reintroducing deer and cattle predators to restore a predator-prey balance. However, these are large-scale and expensive approaches.
Pando’s decline will also impact the local ecology of the area. Aspen forests are often a keystone species in an ecological system. The success of those on either side of the forests on the food chain is greatly impacted by their presence, according to the American Museum of Natural History. Aspen forests like Pando therefore support high levels of biodiversity, and Pando fracking may have significant impacts on various dependent species.
“Aspen forests around the world support outsized biodiversity, but in Pando, overabundant browsers usurp resilience with anticipated negative outcomes on community diversity,” Rodgers wrote.