Hooray for red alder

The Seattle Times has a fine front-page story, about red alder, a tree which can take over disturbed sites and transform them to productive forests. The symbiotic bacteria in its roots allow it to extract nitrogen from the air, which means that as it grows, it fertilizes the soil around it, making it possible for other plants, such as Douglas Fir, to thrive. Also, when alder leaves fall into streams, they add much needed nitrogen to those aquatic systems. And it makes good wood -- fast -- providing foresters with the possibility of a hardwood that can be easily sustainably harvested.