Do you know the difference between a thistle and a purple coneflower? You can learn that and much more when members of the Oklahoma Native Plant Society share their expertise in identifying plants at the Oklahoma Centennial Botanical Garden Saturday. There will be lectures, hands-on examinations of live plants and guided trail walks. In the outdoor activity area, children can make seed balls to start a wildflower garden in front of the temporary Visitor Center. The garden is open through 4pm.