Nature

The Underworld of Oregon Caves National Monument

Island Trail at Walnut Canyon. Walnut Canyon National Monument

The Spell of the White Sturgeon

The Study of Plant Life

Gems in the Smithsonian Institution

The Boy With the U. S. Foresters

Geographic Variation in the North American Cyprinid Fish, Hybopsis gracilis

El Morro Trails: El Morro National Monument, New Mexico

The Lure of the Mississippi

Carlsbad Caverns National Park, New Mexico

Curious Facts in the History of Insects; Including Spiders and Scorpions

A Text-book of Entomology

The Botanical Lore of the California Indians with Side Lights on Historical Incidents in California

Cambrian Ocean World

Making Bird-Friendly Birdhouses

Of Man and Beast

Know Your Chickens

Know Your Cows

Agro-Forestrium Hyperaccumulator Plant To Clean Toxic Plastic Waste & Micro Plastic Waste From Nature

Integrated Environmental Footprint Index (IPAI)