Little trees matter when it comes to water health

While scientists have worried that the disappearance of trees has negatively affected waterways, new research shows the vegetation left behind has helped keep streams and lakes healthy. A team of scientists has found that the small trees left behind in Colorado's forests after logging or that were ignored by the mountain pine beetle have increased their nitrate intake.

Normally, the smaller trees have to compete with the larger trees for nitrate, said lead researcher William Lewis. "But when the big trees are gone, the little trees are sort of released from certain growth restraints imposed by the older trees," he said. "With so much nitrate available in the forest, they are starting to grow faster. What's shocking is that the understory can completely compensate, at least in Colorado, for the loss of the big trees"