Trees don’t actually grow from the ground, physicists find

Trees don’t actually grow from the ground, physicists find

A willow tree that gained 164 pounds over five years grew in soil that lost less than two ounces. Jan Baptist van Helmont recorded that result in the early 1600s, and the arithmetic was difficult to dismiss. The Flemish scientist had planted a 5-pound sapling in 200 pounds of carefully dried earth, watered it for five years, and then weighed both again. The tree had grown dramatically. The soil had barely changed. The numbers pointed away from t…