[Roses West of the Cascade Mountains of Oregon and Washington]

Clustered Wild Rose Clustered Rose, Peafruit Rose, Swamp Rose

Rosa pisocarpa

Synonym: Rosa rivalis

Clustered Wild Rose, Clustered Rose, Peafruit Rose: Rosa pisocarpa (Synonym: Rosa rivalis)

Close-up of the flowers and ternately-compound leaves of clustered wild rose as seen along the Springwater Trail between Gresham, OR and Boring, Or................July 8, 2011.

Characteristics:

The clustered wild rose is a woody shrub to 2.5 meters in height. The stems are usually dark red or occasionally green, and the intertwine. The stems may be bare or if present, the prickles are straight, stout, and borne in pairs at the base of the stipules or petioles.

The leaves have 5-7 pinnately compound leaflets. The leaves are about 1.5 to 4 cm long. The leaflets are ovate and with toothed margins as seen above and at right.

The pink flowers are small and 5-petaled and found in clusters. The individual petals are about 1.5 cm long so the width of the whole flower ranges from 4-5 cm..

The fruits are egg-shaped rose hips, reddish purple in color, and about 1.2 cm long (essentially similar to miniature apples). The sepals remain attached to the base of the hip, and the backs of the sepals are usually coarsely glandular.


Importance:

1. Dried flower petals for scents, potpourri.

2. Rose hips are high in vitamin C, may be made into jam, tea, and used as flavoring.

3. Clustered wild rose may be used as a hedgerow or as an ornamental.

4. Native Americans mashed the leaves together and made a poultice for application to sore eyes, abscesses, and bee stings.

5. The fruits are an important food source by various herbivores and upland game birds. The leaves and twigs are eaten by numerous browsers, and rose thickets provide excellent nesting and escape habitat for songbirds.


Clustered Wild Rose, Peafruit Rose: Rosa pisocarpa

The photo above shows the pinnately compound leaves and clustered rose hips (fruits) of the clustered wild rose.

Habitat:

The clustered wild rose is found in thickets (groups) on moist swampy ground. It is often found in ditches along roads as well as along streams.


Range:

The clustered wild rose may be found from southern British Columbia south to the west of the Cascade summit to northern California.


Close-up sideview of the flower of Clustered Wild Rose, Clustered Rose, Peafruit Rose: Rosa pisocarpa (Synonym: Rosa rivalis) - Prickles of Clustered Wild Rose, Clustered Rose, Peafruit Rose: Rosa pisocarpa (Synonym: Rosa rivalis)

Close-up sideview of the flowers and prickles of clustered wild rose as seen along the Springwater Trail between Gresham, OR and Boring, Or................July 8, 2011. Note the gland-tipped bristles on the outer surface of the calyx lobes and the narrow prickles on the stems.

Clustered Wild Rose, Clustered Rose, Peafruit Rose: Rosa pisocarpa - Clustered Wild Rose, Clustered Rose, Peafruit Rose: Rosa pisocarpa

Note the numerous gland-tipped hairs on the outer surface of the sepals as well as below the inferior ovaries, a characteristic of this species of wild rose.

Paul Slichter