Katniss (Sagittaria sagittifolia) is an aquatic plant that grows around District 12. It grows tall, with leaves like arrowheads and blossoms with three white petals and in the middle of the petals, there is purple pollen. The roots are small blue-ish tubers. The tubers, when boiled or baked, are similar to a potato. Katniss Everdeen was named by her father after this plant. The two would go to the lake to shoot waterfowl and collect Katniss roots. When Katniss was almost twelve years old, and first began to hunt and gather in the woods; katniss was one of the first foods she found there. It was also part of her last meal before leaving for the Capitol.
The katniss plant is also known as "arrowhead," so her name may be interpreted as a reference to her skills in archery. On the other hand, it is both ornamental and useful, parallel to Katniss' varying roles in the Capitol and her own district.
Nowadays, you can find the Katniss plant in Europe and Asia.