How a floating fern withstands the rain

A drop of water on a leaf of the tropical floating fern Salvinia molesta. The tropical floating fern Salvinia molesta has developed sophisticated structures to allow water to roll off its leaves quickly - even during heavy rainfall. This relieves the pressure on the leaves floating on the water surface, but even more importantly, it keeps the stomata open for air exchange. This allows the fern to absorb carbon dioxide which is essential for photosynthesis. This was discovered in an interdisciplinary collaborative project between the working group of Professor James Nebelsick and Dr. Dr. Wilfried Konrad from the Department of Geosciences at the University of Tübingen and Dr. Anita Roth-Nebelsick from the State Museum of Natural History in Stuttgart. In their experiments, the team simulated rainfall and used high-speed cameras to track the path of water droplets slapping onto the fern's leaves. The leaf structures are efficiently adapted to rainfall and may contribute to the strong growth and rapid spread of the fern.