St. Andrew cross (Hypericum, Ascyrum ...

The image showcases two photographs of St. Andrew's Cross (Hypericum ascyron), a plant species native to Europe and Asia, but naturalized in North America.

In the top photograph, the flowers appear yellow due to regular daylight illumination. The lower photograph features the same flowers illuminated by a 365 nm ultraviolet blacklight from Richards Loop Trail in Sam Houston National Forest, Texas.

The top image displays two bright yellow flowers with five long, thin petals and multiple stamens. Each flower rests on three leaves that resemble a cross. One of the leaves has been cropped out of the frame on the left side of the photograph. The lower portion of the photograph is filled by the green leaves of another plant.

The bottom image also features two bright pink flowers with five long, thin petals and multiple stamens. These appear to be the same flowers as in the top photograph. Each flower rests on three leaves that resemble a cross. One of the leaves has been cropped out of the frame on the left side of the photograph. The lower portion of the photograph is filled by the green leaves of another plant.

The top image's background is black, while the bottom image's background is dark blue. This indicates that the photographs were taken at night with a UV light source illuminating the flowers. – AI vision