2024Flora Water Caltrop - First Day Cover

Water caltrop (Trapa natans L.) is a freshwater plant and a relict species, which emerged at the end of the Tertiary Period, during the glacial and postglacial periods.It exhibits two types of leaves: the leaves submerged in the water are rootlike and soon fall off, while the leaves on the water’s surface are buoyant, large and rhombus-shaped, with sawtooth edges.The leaves are a vibrant green in the summer and turn reddish in the autumn, before gradually withering. White flowers are located at the base of the floating leaves. The fruit is a four-horned nut, which is why the plant is known in some countries as water nut. Water caltrops have been harvested for human and animal consumption since ancient times. Lake Skadar provides ideal conditions for the life of this plant species, which is protected by national legislation in Montenegro.