Richard Powers, _The Overstory_

POWERS IS AMONG my very favorite living novelists; this is the seventh I've read (thus, there are five I have not), and it is the best of all of them, I would say.

A recurring structure in the six I had read previously is a kind of double helix: two main plots, seemingly independent, but complementary or reciprocally illuminating in various ways. The two plots seem to run parallel for a while, then unexpectedly intersect.

The Overstory ups the ante: eight strands. Five strands are characters who end up working together as...eco-terrorists, I guess we would have to say, whose efforts to stop redwood logging eventually resort to violence.

Another is a couple whose marriage is unravelling, then arrested in its unravelling by the husband's damaging but not fatal stroke, then finally redeemed, I am going to say, when they (under the influence of the next character I will mention) let the trees reclaim their acreage.

A seventh is a maverick researcher, along Rachel Carson or Jane Goodall lines, whose initially mocked research about the intelligence and communicative abilities of trees gradually wins an audience, then becomes famous, then enacts a terrifying answer to the question posed by an environmental conference, "What is the single best thing a person can do for tomorrow's world?"

An eighth is a wheelchair-dependent computer genius, also profoundly effected by the seventh's book, who thinks, or hopes, that there is a different answer to that question than hers.

Powers' novels have always been marked by muscular yet graceful prose--check--extraordinary but lightly-carried erudition--check--structural ingenuity--emphatic check--and, increasingly, a public call to conscience. In this last category, too, The Overstory vaults over its predecessors. It seems to have gotten through to a fairly wide audience, and that's a reason to be grateful. Maybe hopeful, if that's not asking too much.