Branch arrangement, structure, other features: opposite branching, multi-stemmed, branches very thin

Leaf structure, shape, color, persistence, other features: simple elliptical leaves with entire margins. Leaves are dark green, new growth is red. Leaf length of mature leaves just under two inches. Leaf petioles are reddish brown.

Flower color, size, form, arrangement, blooming period, persistence, other features: Small white flowers growing in clusters on the stem in the leaf axils (hence the scientific name axillaris). 

Fruit size, color (early/ripe), form, persistence, time of year, other features: Berries are dark to black when ripe, edible, 1/4 inch to 1/2 inch in diameter.

Root features: No distinct root features.

Key features for identification: Can have pungent/unpleasant odor, flowers and fruit rest almost directly on the stem (sessile). The leaf petioles remain red/reddish brown as the foliage matures. Leaves tend to be wavy or undulating in their shape, but with a smooth margin (whereas most stoppers have leaves that are flat) though the leaves like many stoppers can be broadly V-shaped. Unlike other stoppers, leaf venation is somewhat distinct though not bold and midrib can be seend from several feet away.

Similar species/often confused with:

red stopper (Eugenia rhombea)
Similar features: Simple opposite leaves, multi-stem, similar size and growth habit
Distinguished by:  Flowers and fruits on short stalks (whereas they are sessile on white stopper); leaf petioles are lime green (reddish brown on white stopper)

redberry stopper (Eugenia confusa)
Similar features: Simple opposite leaves, multi-stem, similar size and growth habit
Distinguished by: Leaves are more narrow and elongated, flowers and fruits on stalks, leaf petioles are a dull green (reddish brown on white stopper)

External links: 

Institute for Regional Conservation:
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