This weird looking growth in Peru could be more than 550 years old, scientists say

Mark Price
·3 min read

A mysterious lumpy growth in Peru that resembles a pile of rocks — only lime green — may count among the world’s oldest plants, according to the U.S Geological Survey.

It’s called the yareta and a team of U.S. and Peruvian researchers has zeroed in on one particular example found on the slopes of southern Peru’s Misti volcano, USGS Volcanoes wrote Wednesday on Facebook.

Tests on the plant (technically called Azorella compacta) indicate it’s about half a millennia old, and may predate the arrival of Columbus in the Americas.

“The species’ slow growth rate suggests that plants may have a longevity of hundreds or possibly thousands of years,” USGS Volcanoes said in its post. “To test this, scientists collected a slice of A. compacta’s cushion and used carbon 14 analyses to figure out how old the plant was at particular depths within the slice.”

What tests showed

The findings suggest the plant may be an astounding 550-plus years old.

  • “At ~6 inches into the cushion, the plant was growing sometime between 1948-1958.

  • At ~11 in, it was growing between 1802-1935.

  • Extrapolating the growth model to the plant’s core at ~28 in depth, suggests that it began growing between 1462-1830.

  • This means that the plant may have begun growing shortly after Misti’s most recent eruption and was undoubtedly growing during many of the ~11 possible episodes of heightened unrest that occurred between the mid-16th Century and 1985.”

This data are important, because the plant’s folds could contain details of the nearby volcano’s history of eruptions, the report says. This includes volcanic ash “that can be dated with the same testing.”

A photo shared by the USGS on Facebook shows the plant looks like a stack of moss-covered rocks in an otherwise drab field of brown grasses. Scientists refer to the plant’s lumps as “cushions.”

“As the plant grows outward from a central root system, compact cushions form from accumulated dead leaves and stems that are progressively overgrown by their tight-knit canopies,” the report states.

The 19,000-foot-tall Misti volcano is of concern to the world’s scientists, because a growing population is building around it, including the city of Arequipa with a population of about 1 million, the USGS said.

“A greater understanding of the volcano’s eruptive history is critical to assessing hazards. Yareta may help researchers learn more about the past, to protect communities in the future,” the report says.

NASA’s Earth Observatory reports Misti has had “five minor eruptions” in the last century, and one “major eruption in the 15th century when residents were forced to flee the city.”

“Despite the obvious hazard, civil defense authorities see it as a remote danger, and city planners are not avoiding development on the volcano side of the city,” NASA reports.

“Human development (is) extending up the flanks of the volcano along gullies which would form natural channels for flows of lava, super heated ash and gas, or melted ice, snow, and mud from the summit snowfield in the event of an eruption.”

The team studying the yareta plant includes the USGS Volcano Disaster Assistance Program, U.S. Agency for International Development, Ingemmet Perú and California Polytechnic State University, the report said.