Plants have long been known as the lungs of the Earth, but a new finding has found they may also play a role in electrifying the atmosphere. Scientists have long-suspected an association between trees and electricity, but researchers in Australia think they may have finally discovered the link. The scientists ran experiments in six locations around Brisbane. They found the positive and negative ion concentrations in the air were twice as high in heavily wooded areas than in open grassy areas, such as parks.