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Hazel Alder



Alnus serrulata




Common: Tag/Smooth Alder, Brookside Alder
Botanical: Alnus rugosa


Eastern US

  • S Maine southward to N Florida
  • N Florida westward to E Texas
  • E Texas northward to central Missouri
  • Missouri northeastward to Maine
  • Absent from most of Ohio and Lower Mississippi Valleys


This species, commonly seen along stream banks and other moist areas at low elevations of the southeastern US, is also known as tag/smooth alder. It is a large shrub or small tree. Leaves are about 2 to 4 inches long and somewhat more than half as wide, with a wavy margin and fine teeth. Male catkins mature in the spring, and after releasing the wind-borne pollen, they fall off. Female catkins appear around the same period but ripen into small cones (a half-inch in length or less) later in the season.