Tall timber found in PNG

Asurvey of Papua New Guinea’s lush primary forests has revealed that the country’s mountains may have the largest trees recorded globally at such high altitudes.

The study was led by Dr Michelle Venter, from Canada’s University of Northern British Columbia, and involved the University of Queensland (UQ) and James Cook University.

“Current thinking is that tall mountains make small trees,” Venter says. “However, we recorded more than 15 tree families with individuals growing to 40-metres tall at extreme altitudes, which brings this assumption into question.”

The researchers found that the forest biomass in PNG had a peak at altitudes between 2400 and 3100 metres, altitudes where forests struggle to reach more than 15 metres in other parts of the world.

Dr John Dwyer, from UQ, says researchers became excited when they realised the unique climate conditions found on PNG’s mountain tops were remarkably similar to those of temperate maritime areas known to grow the largest trees in the world.

The world’s tallest known tree is a 115.8-metre coast redwood in California, and the second-tallest is a 99.82-metre mountain ash in Tasmania.

Coast redwoods (pictured) occur at elevations up to about 920 metres, while the Australian mountain ash occurs in cool mountainous areas to 1000 metres, considerably less than the PNG altitudes.

“The study may force a re-think of what we know about the ideal environments for growing very large trees,” according to Dwyer. ■