Butterbur

Petasites hybridus. An interesting plant of roadsides, meadows and streambanks. These flower spikes come up first and are followed by the leaves. The leaves are very large and commonly grow to a metre in width. They look like giant rhubarb. I suppose if the flowers came after the leaves no pollinating insects would ever find them.
The leaves were at one time used for wrapping butter - hence the common English name.