The Ribeauvillé forest, around Riquewihr, encompasses the wooded regions of the Rhine valley and the Ill plain. It is a large area of 27,856 acres (11,273 ha) with a continental climate. Summers are hot and can even become humid when getting close to the Rhine. The ash tree is the predominant species of the fluvial valley and the Ill plain. They are also home to numerous English oaks and black and white poplars. The presence, at shallow depth, of a phreatic table favors and determines the luxuriant growth of the forest.