[The Rose Family West of the Cascade Mountains of Oregon and Washington]

Indian Plum, Osoberry, Oso-berry

Oemleria cerasiformis

Synonym: Osmaronia cerasiformis

Indian Plum, Osoberry, Oso-berry: Oemleria cerasiformis

The dangling inflorescence and newly emerged, erect leaves of osoberry as seen at the author's home in Gresham, OR.........March 29, 2009.

Fruit of the osoberry at right.
Characteristics:

The osoberry is a deciduous shrub to small tree with one to several erect or ascending stems to 5 meters high. The bark on young twigs and older branches is smooth, deep reddish-brown with round, gray pores. The buds are bright green in winter and then turn red by early spring. The leaves are simple with pinnate venation, and they alternate on the stems. They are bright green above, paler and waxy on their undersides. The leaves are oblong or lance-shaped and range from 5-15 cm long and 2-4 cm wide. The leaf margins are entire. Young leaves taste like cucumber, while the older leaves become bitter. Young leaves stand upright or at a 45 degree angle from the twig.

The osoberry is one of the earliest shrubs to flower in the spring, often flowering at low elevations by early March. Flowering precedes or coincides with the emergence of the leaves. The flowers are creamy greenish-white, 5-petaled, and hang in clusters from the tips of the stems. Female flowers have a pleasant odor while the male flowers smell like cat urine. The fruits are yellowish-red turning deep purple upon maturation.


Importance:

The fruits are eaten by birds and small mammals. They are often used as nesting habitat by small songbirds. Native Americans ate the edible fruits either fresh or dried. They also made preserves from the fruits. The leaves were consume in small amounts in salads.


Habitat:

The osoberry may be found in moist, open woods, along the edges of open woods, and along roadsides or streambanks.


Range:

The osoberry may be found from British Columbia south to the west of the Cascades to the west side of the Sierra Nevada in California.


Inflorescence of Indian plum, Osoberry: Oemleria cerasiformis - Male flower of Indian Plum, Osoberry, Oso-berry: Oemleria cerasiformis (Synonym: Osmaronia cerasiformis) - Male flower of Indian Plum, Osoberry, Oso-berry: Oemleria cerasiformis (Synonym: Osmaronia cerasiformis) - Indian Plum, Osoberry, Oso-berry: Oemleria cerasiformis (Synonym: Osmaronia cerasiformis)

These 4 photos show close-ups of the inflorescence and flowers (in this case, male flowers) of osoberry as seen at the author's home in Gresham, OR........March 29, 2009.

Indian Plum, Osoberry, Oso-berry: Oemleria cerasiformis (Synonym: Osmaronia cerasiformis)

Osoberry in bloom along the Springwater Trail near Powell Butte to the west of Gresham, OR..........April 9, 2011.

Indian Plum, Osoberry, Oso-berry: Oemleria cerasiformis (Synonym: Osmaronia cerasiformis) - Maturing fruits of Indian Plum, Osoberry, Oso-berry: Oemleria cerasiformis (Synonym: Osmaronia cerasiformis)

Maturing fruits (left) of osoberry as seen at Camassia Nature Preserve, West Linn, Oregon..........April 10, 2015. The photo at right shows the maturing fruits of osoberry as seen at Nob Hill Park in St. Helens, OR........April 3, 2016.

Raceme of Indian Plum, Osoberry, Oso-berry: Oemleria cerasiformis (Synonym: Osmaronia cerasiformis) - Raceme of Indian Plum, Osoberry, Oso-berry: Oemleria cerasiformis (Synonym: Osmaronia cerasiformis)

Male flower of Indian Plum, Osoberry, Oso-berry: Oemleria cerasiformis (Synonym: Osmaronia cerasiformis) - Young leaves of Indian Plum, Osoberry, Oso-berry: Oemleria cerasiformis (Synonym: Osmaronia cerasiformis) - Male flower of Indian Plum, Osoberry, Oso-berry: Oemleria cerasiformis (Synonym: Osmaronia cerasiformis)

Additional close-up photos of the racemes, young leaves and male flowers of osoberry as seen along the Springwater Trail between Palmblad and Rugg Roads immediately to the east of Gresham, OR.........April 2, 2011. It appears that only about 10% of plants are females.

Lower leaf surface of Indian Plum, Osoberry, Oso-berry: Oemleria cerasiformis (Synonym: Osmaronia cerasiformis)Upper leaf surface of Indian Plum, Osoberry, Oso-berry: Oemleria cerasiformis (Synonym: Osmaronia cerasiformis)


Paul Slichter