It has the smallest flower of any of the 28 species of cacti found in the deserts of California. From petal tip to petal tip a pencil Cholla flower is a little more than a half inch in diameter ...

As far as width goes, a pencil eraser is just under ¼ inches wide. This makes it the perfect size for many seeds. However, you may encounter seeds that don't quite fit this size, either from ...