John McPhee's geology books

Not really boring at all, but An Immense World is amazing.

Have you read The Backyard Bird Chronicles yet?
https://www.goodreads.com/book/show/194803881-the-backyard-bird-chronicles

Lots of stuff by E.O. Wilson, if you haven't already read him

Thanks, everyone, these are great suggestions with quite a few I haven't read yet.

Here are a few of my favorites that haven't been mentioned yet, in case anyone else is looking.

Proust and the Squid by Maryanne Wolf
The Nature of Oaks by Doug Tallamy
A World on the Wing by Scott Weidensaul (bird migration)
The Genius of Birds by Jennifer Ackerman
The Invention of Nature by Andrea Wulf (bio of Humboldt)
The Language of Butterflies by Wendy Williams

The Arbornaut

I loved Fuzz but there’s a lot of destruction and mayhem so perhaps not as soothing as you’d like.

Down from the Mountain — about efforts to keep bears out of farmland in Montana.

In the Conpany of Wolves

Also the series the best American science writing of (fill in the year) often had really great pieces on nature. Its essays and magazine articles so each chapter is nice and manageable and you can skip the ones that don’t interest you.

I also immediately thought of A Walk in the Woods by Bill Bryson.

For birds: The Evolution of Beauty is a wonderful book written by an ornithologist comparing and contrasting the evolution of birds to human mate selection. It's brilliant, and beautiful, and easy to read.

A Walk in the Woods by Bill Bryson maybe? I adored that book. It's not exactly what you're looking for but you might love it!

Would also add Braiding Sweetgrass and the American Chestnut.

In the more general nature/science area, I also liked Breath, the lives of a cell, why we sleep, power, sex, suicide (about mitochondria),

Spring in Washington by Louis Halle. Beautiful writing.

I really liked Winter World by Bernd Heinrich. He wrote a bunch of books and has a soothing writing style.

There are the first tier of common suggestions, all great books (Hidden Life of Trees, Search for the Mother Tree, Immense World, Entangled Life, Gathering Moss, H is for Hawk) but it sounds like you've probably covered these. (Actually, I wouldn't call H is for Hawk soothing at all, since it also deals with the author's loss of her father.)

Others I have really liked:
Enchantment by Katherine May
A Brief History of Earth by Andrew Knoll
Otherlands by Thomas Halliday

Less well known but much liked:

A Natural History of North American Trees
by Donald Culross Peattie (written in the 1950s, a classic, excellent writing)


On my list to read:
Rooted by Lynda Lynn Haupt

I need a nice, soothing, slightly boring book about nature to read to calm my anxiety.

Something about trees or birds or geology, etc. I've read quite a few of these already, so feel free to offer up some more obscure suggestions.