Hungry Deer Pose Threat to World's Biggest Organism

It looks for all the world like a giant grove of trees, but this one has a twist: The 106-acre stand of aspens in Utah known as Pando is actually a single organism—and the biggest organism in the world at that. The trees don't grow from seeds but from shoots connected to the same root system. In an essay at the Conversation, Richard Elton Walton of Newcastle University writes that all is not well at the site for a number of reasons. One of the biggest is an expanding population of deer and elk that munch on new shoots, the "clonal stems" of the organism. The result is that Pando is seeing very little new growth, with the exception of one fenced-off area that keep the grazers out. (Fencing is an expensive overall solution given Pando's size.)

Meanwhile, the existing older stems face trouble of their own, including at least three diseases: sooty bark canker, leaf spot, and conk fungal disease. And on top of all that, the region is generally seeing warmer temperatures earlier in the year, plus reduced water, factors that hamper the growth of leaves. Walton takes a big-picture view, noting that Pando has existed for perhaps 14,000 years. But he also argues that its complex ecosystem is clearly under stress and needs help. "It’s these moments that remind us that we have plants, animals and ecosystems worth protecting," he writes. "In Pando, we get the rare chance to protect all three." (Read the full essay.)