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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

Human Product Number - 69

Veterinary Product Number - 69


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.