Trees In Trouble: Wildfires, Infestations, and Climate Change. 2020. Counterpoint Press.

The troubling story of the devastating and compounding effects of climate change in the Western and Rocky Mountain states, told through in-depth reportage and conversations with ecologists, professional forest managers, park service scientists, a burn boss, activists, and more.

It isn’t all doom. Trees In Trouble revels in the smells and sights of western trees, as well as their amazing adaptations to life here. It also identifies practices that need to be adopted to optimize our future forests. They need public support.

Trees In Trouble was placed on the Longlist (10 candidate books) for the 2021 Young Adult Science Book Award of the American Association for the Advancement of Science. Past winners include Lab Girl, The Wild Trees, and The Immortal Life of Henrietta Lacks.

“Mathews identifies the urgent concerns, the conflicts between related agencies, and possible solutions to the problems that will only get worse if we don’t act on them immediately. Equally compelling is his sharing of new knowledge about the wonder of trees, how they work, how they interact, and just how crucial they are to our survival. Trees in Trouble is an essential read for people concerned about the long-term future of our continent.”

—Chris La Tray, author and bookseller, Fact and Fiction Books, Missoula

Counterpoint Press (Berkeley) 304 pages softcover 6 by 9 inches. $17.95. Also in hardcover $26.

To support independent bookstores, I recommend purchasing from Bookshop.

Cascadia Revealed: A Guide to the Plants, Animals, and Geology of the Pacific Northwest Mountains. Timber Press (Portland) 586 pages, 6 by 8.5 inches. $27.95.

The  third edition of Cascade-Olympic Natural History was first published by Timber Press under the name Natural History of Pacific Northwest Mountains. The second printing, retitled Cascadia Revealed, has around forty minor updates. The most conspicuous change from Cascade-Olympic Natural History is color photos—more than a thousand of them—now throughout the book on the same page I discuss the species they illustrate. There are also 131 additional species, and well over 100 new names for species that were in Cascade-Olympic Natural History.

I expanded the geographic coverage to include the mountains of southwest British Columbia and also the Coast Ranges in Oregon and Washington.  And of course I added countless new findings and understandings.

Rocky Mountain Natural History: Grand Teton to Jasper is a comprehensive field guide to plants, animals, fungi, lichens, geology, and overall ecology of this spectacular ecoprovince extending from the edge of the Great Plains westward to include the Columbia Mountains in British Columbia, the Selkirks in Washington, and the Wallowas in Oregon. It features exquisite line art of insects, by Eric Eaton, and photos of butterflies by Will Kerling.

Rocky Mountain Natural History is out of print. I am currently writing a much-expanded new edition for Mountaineers Books. It will cover all of the U.S. Rockies, from the Canadian border to Santa Fe, New Mexico, with color photos throughout. Title to be determined.

Raven Editions 2003. 656 pages, 64 in color, 5.25 by 8 inches. $26.00.

A field guide for those who go afield in fear of guides, this 656-page tome is by turns hilarious, stern, ominous, playful, instructive, instructed, and is more linguistically alive (“Sphagnum species specialize”) than any member of the field guide family I’ve ever encountered.

—poet Chris Dombrowski’s Bookshelf at Orion

Cascade-Olympic Natural History: A Trailside Reference, sold more than 43,000 copies; copies may sometimes be obtained through used book resellers. The book is out of print.

64 pages of color photos, plus the inimitable drawings of vascular plants by Jeanne R. Janish, and lovely exclusive drawings of mosses by Barbara Stafford Wilson.

Raven Editions 1988 and (Second Edition) 1999. 624 pages, 64 in color, 5.25 by 8 inches.

“Highly literate and ceaselessly entertaining, Daniel Mathews’ trailside reference offers more than simply flora and fauna. It is a grand read, wise and comic, and indipsensible to anyone who cares about the Northwest.”

—David Guterson, author, Snow Falling on Cedars etc.

Also written by Daniel Mathews is America From the Air: a Guide to the Landscape Along Your Route. It was co-authored with James S. Jackson and published by Houghton Mifflin. To minimize weight for fliers with laptops, each print copy is packaged with a PDF copy on CD.

2007. 386 pages. 9.25 by 7.5 inches. $19.95.

“I think it might, quite possibly, be the best book I have ever read. . . . Mathews and Jackson are the true encyclopedists of our era. Even if all our knowledge were lost to us, and humanity were left, a hobo with shopping cart, trudging through a benighted post-apocalyptic world, a single copy of “America From the Air” would prove sufficient to resurrect the entire civilization, from Paris Hilton to Paris, Texas.”

—author Will Self, reviewing America From the Air in The Los Angeles Times

Northwest Mountain Wildflowers is currently unavailable. If you already have it it will still work on iOS 10 and earlier, but it will not work if you upgrade to iOS 11. A field guide you carry in your iPhone or iPod, it weighs nothing, and doesn’t require a cellular or wi-fi connection, as it loads completely onto your device.


It describes 549 species of herbaceous flowering plants within a range stretching from the coast to Grand Teton and Jasper National Parks. Lots of the species pages have more than one photo, for a total of 925 identification photos; dozens more photos illustrate flower parts, families, regional geography, and natural history “extras.”

This app is crammed full of well-written natural history. Think of it more as a complete ebook than a mere app; and yet, being an app, it has highly flexible search and index functions that allow you to quickly find your flower species via any number of paths. Display your search results either as a list or as a sheet of thumbnails of flowers, from which you pick your flower visually.

Comments from user reviews:

“I have purchased and used every flower guide app out there and this app is definitely the best. The interface is simple and effective.”

“an amazing app, and a superb translation of a wonderful natural history field guide. Great photos. Very workable for identification in the field, and wonderful (literate!) natural history information. It goes deep as well as broad.”

“I don’t think you can overestimate the value of a field guide that weighs so little.”

Northwest and Rocky Mountain Trees & Shrubs, the companion app covering the woody plants, is currently unavailable. If you already have it it will still work on iOS 10 and earlier, but it will not work if you upgrade to iOS 11.

Its 176 species accounts are illustrated with 526 photos—more than three per species. Their natural history discussions are thorough: you’ll learn what makes the Northwest’s forests the global superstars that they are, and what threats they face from climate change, epidemic pests, loss of top predators, encroaching development, fire, and suppression of fire. You can also find medicinal and food uses, biographies of the naturalist-explorers the plants are named after, help with pronouncing and understanding the scientific names, and more.

Both apps were developed by Chris Leger of Earthrover Software. His interface is easier to use and more stable than other iPhone field guides. Choose among several paths to your plant: just check off your location and then scroll through thumbnail photos by color; use flower structure and leaf features for a precise search; browse in the index, viewing your choice of common names, scientific names, or both mixed together; look for them by plant family; or enter keywords and let the app search for those.

The text in the apps was adapted, expanded, and updated from the two Raven Editions books.