Semiaquatic dark green, leafy plant of clear, cool shallow water of springs, seeps, and quietly flowing streams; submerged or partly emergent.  Its hollow herbaceous stems are erect and roots tend to form at lower nodes.  Leaves are pinnately compound and alternate on the stem.  Tiny four-petaled white flowers form a raceme.  Watercress is native to Europe but became widely naturalized in our state.  The shoots of watercress have a pungent taste and can be used as a garnish.