Latin: Ilex verticulata

Other common names: common winterberry, black-alder, northern holly, swamp holly, michigan holly

Mature Height: 15 ft

Soil / Climate: Grows in wet areas near swamps, ponds, or wet woods.  Prefers rich, acidic soils.  Hardy.  Can tolerate partial shade, but will produce more fruit if planted in full sun.

Notes: Long, oval, green leaves that turn brown to black in autumn.  White flowers.  Bright scarlet fruit grows in clusters and persists throughout winter.  Prized ornamental often used for Christmas decorations. Only female produces fruit, and must have a male nearby for pollination.  Male plants have flowers in clusters.  Female plants have single flowers, or in groups of 2 or 3.  Female plants have flowers with a distinct green miniature "knob" in the center (the immature ovule), while male flowers are loaded with yellow anthers (the pollen-bearing structures)
Winterberry male plants need to be carefully matched with female plants (mismatch of blossom times by even one week will result in poor to non-existent pollination and little or no fruit set on female plants); in many cases, the male plant is simply labelled "early" or "late" in reference to its relative bloom time
if a large landscape planting of this species exists, and little or no fruit production occurs year after year, then buy both an early male and a late male, plant very close by, and observe if fruit production dramatically jumps