Alder trees produce nodules on their roots, which foster the growth of bacteria which infuse soil with nitrogen. They only live for around 100 years, then die, having transformed the soil into a place where many other plants and trees can now grow.

As they grow, the larger lower branches dry, and fall to the ground. They shed firewood like fruit. I collect them and use them to cook in the rocket stove, and to heat stream water in the tub.