Dennis Drabelle, a former contributing editor of Book World, writes frequently about the environment.

Terry Tempest Williams is a force of nature in at least two ways. First, she pleads forcefully on behalf of the natural world, especially national parks, wilderness areas and endangered species. And, second, she writes as she damn well pleases.

If Williams wants to use Canyonlands National Park as an excuse to recycle a number of letters she wrote — some to living souls (environmental activist Tim DeChristopher, Interior Secretary Sally Jewell), others to recipients long in their graves at the time of writing (John Wesley Powell, Edward Abbey) — she will do so. If she wants to bring up the restraining order she once obtained against one of her brothers without explaining what provoked it and how the feud ended, she’ll do that, too. And if she decides that the Chinese artist-cum-activist Ai Weiwei deserves a lengthy treatment in a piece on Alcatraz Island (where his work was on display at the time of her visit), she won’t be deterred.

Williams takes these and other chances in her new book, “The Hour of Land,” a collection of a dozen essays devoted to the state of the American environment as reflected in our national parks. (Sticklers take note: Williams uses the term “national park” broadly, as synecdoche for most of the categories in the national park system: park, monument, historic site, battlefield, seashore, recreation area.) The essays are interspersed with park-related photographs taken by contributors from Carleton Watkins to Ansel Adams to Anonymous, and Williams also borrows epigraphs from the poet Jorie Graham.

But even with the book’s far-flung collaborators and long reach, the author’s trademark poetic prose dominates every page. The following image, about Gulf Islands National Seashore as seen from a plane, can stand for a myriad of others: “The Mississippi Delta comes into full view like a great nurturing hand smoothing the edge of the continent.” And here’s a striking passage from a piece on Big Bend National Park in Texas: “Most deserts have a memory of the sea and here is no exception. Fossils embedded in the limestone create an ancient brocade woven through the stratigraphy of stone.”

"The Hour of Land: A Personal Topography of America's National Parks" by Terry Tempest Williams (FSG)

As that generalization about the desert suggests, Williams — who comes from an old Utah family — knows the West well. Maybe too well, to the point where the multitude of threats to Western ecosystems, especially threats posed by oil and gas companies, can prey on her mind. Where does she go for relief? Why, to eastern national parks, notably Acadia. “It is here in ‘the settled wild’ of Maine that I find sanctuary from the painful politics surrounding western wilderness,” she writes. “I don’t know enough to have my heart broken in the east.”

Williams justly refers to herself as “a storyteller,” and one of her best stories has to do with the aforementioned DeChristopher. Influenced by Abbey, DeChristopher got creative in trying to prevent the Bureau of Land Management from auctioning off mineral leasing rights to environmentally sensitive public lands in Utah. His tactic was to join the auction, outbid the avid corporations and then renege — as well he might, since he came out as the winner of 14 bids, totaling $1.8 million that he could not even begin to scrape up. DeChristopher paid dearly for his monkey-wrenching (a term for eco-sabotage inspired by Abbey’s 1975 novel, “The Monkey Wrench Gang”): a felony conviction, for which DeChristopher was sentenced to two years in jail. When last mentioned by Williams, though, he is not only out on parole but also “a graduate student at Harvard University Divinity School on a presidential scholarship.”

In places, “The Hour of Land” reads as if it had been rushed into print for this year’s National Park Service centennial. To take just the essay on Theodore Roosevelt National Park, Williams tells us twice that the park’s beleaguered superintendent finds it easier to deal with the chief executives of energy companies than with North Dakota’s governor and legislature. (The crux seems to be that, desirous of protecting their firms’ images, the CEOs are open to compromise, whereas the state officials can’t see past their fixation on fostering an economic boom.) And although elsewhere in the book Williams fulminates against war with regularity, here she celebrates the park’s namesake as an environmental visionary, with nary a mention of Roosevelt’s role as one of the loudest warmongers in U.S. history. (What, pray tell, ravages the environment more than warfare?)

Williams saves a surprise for the end: a dollop of optimism. She portrays the fossil-fuel industry as making “its last desperate cries,” although she wonders if the industry hasn’t already set in motion forces that will destroy “not only our most revered public landscapes but also the planet.” A few pages later, she adds, “After spending a lifetime immersed in our national parks, I believe we are slowly learning what it means to offer our reverence and respect to the closest thing we as American citizens have to sacred lands.”

Yes, those sentiments may smack of wishful thinking. But after all it was a mentor of Williams’s, Wallace Stegner, who called wilderness “the geography of hope.”

The Hour of Land
A Personal Topography of America’s National Parks

By Terry Tempest Williams

Sarah Crichton Books/Farrar, Straus and Giroux. 395 pp. $27