Rosa pisocarpa
Encyclopedia
Rosa pisocarpa is a species of rose
known by the common name cluster rose or swamp rose. It is native to western North America from British Columbia
to northern California
, where it generally grows in moist habitats. It is a shrub
sometimes forming a thicket, and growing up to 2.5 meters tall. The stems can be dark red or blackish and are often studded with straight, paired prickles
at nodes. The leaves are each made up of several toothed oval leaflets, the terminal leaflet up to 4 centimeters long. The inflorescence
is a cyme of up to 10 flowers with pink petals each up to 2 centimeters in length. The fruit is a rose hip
about a centimeter wide. The hips are pear- or egg-shaped and borne in clusters, and are decorative in fall and early winter, when they are red or reddish-purple and contrast with yellow foliage. Fall foliage can be yellow or dark red.
R. pisocarpa grows in riparian areas, along roadside ditches, in powerline right-of-ways, along fencerows and hedgerows, in wetland buffers and woodlands.
R. pisocarpa is used in wetland restorations and in native plant landscaping. Its thorny thickets and numerous, persistent hips provide shelter and food for birds and other small wildlife. Deer browse new stems and foliage.
R. pisocarpa hosts gall-making wasps
of the family Cynipidae, genus Diplolepis, in the insect class Hymenoptera
. Two species are D. polita, which makes bristly round red or green galls on leaves, and D. rosae, the mossy rose gall, which makes large, mossy, feathery, greenish or yellowish growths on stems.
Rose
A rose is a woody perennial of the genus Rosa, within the family Rosaceae. There are over 100 species. They form a group of erect shrubs, and climbing or trailing plants, with stems that are often armed with sharp prickles. Flowers are large and showy, in colours ranging from white through yellows...
known by the common name cluster rose or swamp rose. It is native to western North America from British Columbia
British Columbia
British Columbia is the westernmost of Canada's provinces and is known for its natural beauty, as reflected in its Latin motto, Splendor sine occasu . Its name was chosen by Queen Victoria in 1858...
to northern California
California
California is a state located on the West Coast of the United States. It is by far the most populous U.S. state, and the third-largest by land area...
, where it generally grows in moist habitats. It is a shrub
Shrub
A shrub or bush is distinguished from a tree by its multiple stems and shorter height, usually under 5–6 m tall. A large number of plants may become either shrubs or trees, depending on the growing conditions they experience...
sometimes forming a thicket, and growing up to 2.5 meters tall. The stems can be dark red or blackish and are often studded with straight, paired prickles
Thorns, spines, and prickles
In botanical morphology, thorns, spines, and prickles are hard structures with sharp, or at least pointed, ends. In spite of this common feature, they differ in their growth and development on the plant; they are modified versions of different plant organs, stems, stipules, leaf veins, or hairs...
at nodes. The leaves are each made up of several toothed oval leaflets, the terminal leaflet up to 4 centimeters long. The inflorescence
Inflorescence
An inflorescence is a group or cluster of flowers arranged on a stem that is composed of a main branch or a complicated arrangement of branches. Strictly, it is the part of the shoot of seed plants where flowers are formed and which is accordingly modified...
is a cyme of up to 10 flowers with pink petals each up to 2 centimeters in length. The fruit is a rose hip
Rose hip
The rose hip, or rose haw, is the fruit of the rose plant, that typically is red-to-orange, but ranges from dark purple to black in some species. Rose hips begin to form in spring, and ripen in late summer through autumn.-Usage:...
about a centimeter wide. The hips are pear- or egg-shaped and borne in clusters, and are decorative in fall and early winter, when they are red or reddish-purple and contrast with yellow foliage. Fall foliage can be yellow or dark red.
Ecology
R. pisocarpa has a wetland indicator status of FAC for the Pacific Northwest (region 9) and FACU for California (region 0). It grows in full sun in the northern and wetter portions of its range, but also tolerates partial shade, and can grow in dry or lean soils.R. pisocarpa grows in riparian areas, along roadside ditches, in powerline right-of-ways, along fencerows and hedgerows, in wetland buffers and woodlands.
R. pisocarpa is used in wetland restorations and in native plant landscaping. Its thorny thickets and numerous, persistent hips provide shelter and food for birds and other small wildlife. Deer browse new stems and foliage.
R. pisocarpa hosts gall-making wasps
Gall wasp
Gall wasps , also called Gallflies, are a family of the order Hymenoptera and are classified with the Apocrita suborder of wasps in the superfamily Cynipoidea...
of the family Cynipidae, genus Diplolepis, in the insect class Hymenoptera
Hymenoptera
Hymenoptera is one of the largest orders of insects, comprising the sawflies, wasps, bees and ants. There are over 130,000 recognized species, with many more remaining to be described. The name refers to the heavy wings of the insects, and is derived from the Ancient Greek ὑμήν : membrane and...
. Two species are D. polita, which makes bristly round red or green galls on leaves, and D. rosae, the mossy rose gall, which makes large, mossy, feathery, greenish or yellowish growths on stems.