Chinese pistachio trees at Boyce Thompson Arboretum State Park. Arizona's oldest and largest botanical garden. Featured are plants from the world's deserts, towering trees, captivating cacti, sheer mountain cliffs, a streamside forest, panoramic vistas, many natural habitats with varied wildlife, a desert lake, a hidden canyon, specialty gardens and more.

The Arboretum was founded in the 1920s by mining magnate Col. William Boyce Thompson. In 1917 Col. Thompson served as co-leader of a Red Cross mercy mission to Russia, where he came to understand the importance of plants as the ultimate source of a large portion of mankind's food, clothing, and shelter. It was then, that he determined to use his great wealth to improve the use of plant resources. The Arboretum is one of his legacies.