Nature

The Power of Plants

Healing with Roots

The Call of the North

The Pleasures of England

Texas Rocks and Minerals: An Amateur's Guide

Sunshine

Birds of the National Parks in Hawaii

Ferns of Hawaii National Park

Fossil Forests of the Yellowstone National Park

The Land of Enchantment: From Pike's Peak to the Pacific

Birds in Legend, Fable and Folklore

Food Sources

Mystic Peak Legends

The Geologic Story of Palo Duro Canyon

World Fish

Lassen Trails: A Brief Guide to the Trails of Lassen Volcanic National Park

Shaggycoat

The Underworld of Oregon Caves National Monument

The Geology of D.A.R. State Park, Mt. Philo State Forest Park, Sand Bar State Park

Little Frog Wonders