The Overstory

Powers' 2018 novel, which won the Pulitzer Prize, follows nine characters whose lives connect to trees, structured in four sections named Roots, Trunk, Crown and Seeds. The first section gives each character a self-contained origin story, and the later sections bring several of them together in forest activism in the Pacific Northwest.

The scientific material concerns forest ecology, particularly research showing that trees communicate through fungal networks and chemical signalling, share resources across species, and function as connected systems rather than as competing individuals. The character Patricia Westerford, whose research is rejected and later vindicated, is based loosely on Suzanne Simard and on Diana Beresford-Kroodsby.

The argument the novel makes is about timescale. Powers structures the book so that human concerns are set against processes operating over centuries, and his implicit claim is that the inability to perceive slow change is what permits its destruction. The activism sections cover the tactics used in old-growth forest campaigns and their failure. One character, a programmer building a world simulation game, connects the ecological argument to technology and to the question of whether a system can be modelled well enough to be understood.

The novel is long and the structure means that several characters receive substantial development and then little resolution. Critics have objected that the human characters function as vehicles for the argument. The science is presented accurately in outline, though some of the popular claims about tree communication have been contested by other researchers since. Its interest for a general reader is the treatment of slow processes and the inability of institutions to act on them.