Multiflora Rose (Rosa multiflora)
Family:
Rose Family (Rosaceae)
Other Names:
Japanese rose, rambler rose, wild rose.
Origin and Distribution:
This species was introduced from its native Asia into the U.S. in the early 1800's as an ornamental shrub. Later, it was widely planted as cover for wildlife and to help control soil erosion. In the 1950's, it was common to plant multiflora rose as a 'living fence' that was more permanent and economical than wire fence. However, its aggressive nature made it a noxious weed. Now, it is found growing in uncultivated and unmowed areas including roadsides, fencerows, abandoned pastures, and open woods. In Ohio, it is especially troublesome in the southeastern part of the state. The species is tolerant of many soil conditions, but is not usually found growing in standing water or extremely dry habitats.
Plant Description:
Multiflora rose is a perennial shrub with arching, prickly stems that climb over other plants and form dense thickets. Plants can grow 6 to 10 feet tall, (sometimes up to 15 feet) and 9 to 13 feet wide. This species is characterized by its showy white flower clusters in the spring and small, bright red fruits in the fall. Reproduction is by seeds, horizontal stems (stolons) that can root at the nodes, and shoots which can root at their tips.
Root System:
Multiflora rose produces a vigorous root system that can persist for many years.
Stems:
Stems are branched, woody and covered with long, stiff, curved thorns. Stems can grow up to 13 feet long. They typically grow upright for about 6 feet, then droop to the ground. Some stems may creep along the ground. Many stems grow from a single root system to form a dense clump.
Leaves:
Leaves are alternate (1 leaf per node) and consist of 5 to 11 (usually 9) finely toothed, oval leaflets that are less than 1 1/2 inches long. Leaves attach to stems by way of stalks (petioles). Located at the base of each petiole and extending about half of its length are a pair of fringed leaf-like appendages (stipules).
Flowers:
Small white flowers form showy, pyramid-shaped clusters at the ends of branches. The fragrant flowers are 1/2 to 3/4 inch wide (sometimes up to 1 1/2 inches wide) and consist of 5 white (rarely pinkish) petals.
Fruits and Seeds:
The fleshy, round fruits, or hips, are only 1/4 inch wide. They turn bright red at maturity. Hips often persist on the plant through winter becoming dry, leathery capsules by the following spring. Each hip contains 6 to 12 straw-colored seeds.
Similar Species:
Multiflora rose can be distinguished from other rose species (Rosa spp.) by its clusters of small white flowers and fringed stipules (leaf-like appendages) at the base of the leaf petioles.
Biology:
Multiflora rose blooms in May and June. One multiflora rose can produce up to 500,000 seeds yearly, and seeds buried in soil can remain viable for 10 to 20 years. Birds are fond of multiflora rose hips and tend to eat and then disperse seeds over large areas. A single multiflora rose seedling or shoot can produce a patch more than 33 feet in diameter.
Once established, multiflora rose is difficult to control. Mowing inhibits seedling establishment. However, control of larger plants may require digging, pulling, or cutting and then treating the stump with herbicide to prevent resprouting. Biological control programs are being developed that use disease and seed predators to help control multiflora rose.
Toxicity:
None known.
Facts and Folklore:
The genus Multiflora means 'many flowered'.
Multiflora rose is sometimes used as rootstock for propagating other roses.
In the 1960's, the Virginia Department of Highways planted multiflora rose in interstate medians as a means of reducing headlight glare and as a crash barrier.
Multiflora rose seedling with cotyledons and 3-4 true leaves.
Multiflora rose seeds.
Multiflora rose stem; note the stout thorns.
The compound leaves of multiflora rose.
A close-up of multiflora rose flowers.
A field infested with multiflora rose.
Close-up of multiflora rose fruit.
A cluster of multiflora rose fruit.
A cluster of multiflora rose fruit.