Underwater roots of Black Alder (<i><a href="https://en.wikipedia.org/wiki/Alnus_glutinosa" class="extiw" title="en:Alnus glutinosa">Alnus glutinosa</a></i>). River Cabrera, León (Spain)
<a href="//commons.wikimedia.org/wiki/User:David_Perez" title="User:David Perez">David Perez</a>
CC BY 3.0
<span class="int-own-work" lang="en">Own work</span>