Note the giant mushroom in the middle of the design... do you see it?! 

This vintage tank top by Profile Prints, Inc. is a true gem from the 1960s. With its vibrant yellow color and "Spokane USA Children of the Sun" print, it exudes a hippy vibe that is perfect for the free-spirited fashionista. Made from a comfortable cotton blend, it is unisex and suitable for any gender.This original piece was made in the United States and is a must-have for any vintage clothing collector. Its unique look and feel make it a standout addition to any wardrobe. Don't miss out on the chance to own a piece of fashion history. Size Medium.

Spokane – An Indian word meaning “Children of the Sun” or “Sun People”.

or

Could be a leftover item from the Children of the Sun cult!