Multiflora rose is a medium-sized, thorny shrub with a spreading growth form, often forming thickets.
Leaves are alternate, compound, divided into 5–11 leaflets (usually 7–9). Each leaflet is broadly oval and toothed along the edge.
Blooms May–June. Flowers are clustered, numerous, white, ¾–1½ inches across. The clusters are rounded or pyramidal and 3–6 inches across.
Fruits are small, firm, red hips that may remain on the plant well into winter.
Examine the small leafy appendage (stipule) that hugs the stem at the base of each compound leaf. On multiflora rose, the edges of the stipules are fringed with many teeth, resembling a comb. Our native roses, however, have stipules with smooth margins (no teeth).
Height: to 15 feet; root crown diameter: to 8 inches.
Occurs in old fields, pastures, and roadsides. May occur in dense forests, particularly in disturbed areas such as treefall gaps and along streams. Multiflora rose has a wide tolerance for different soil, moisture, and light conditions but does not grow well in standing water. First introduced to North America in 1886 as a rootstock for ornamental roses, then planted widely for erosion control and as living fences, it soon spread and became seriously invasive.
Invasive. Native to Japan. During the last century, federal and many state conservation agencies promoted the planting of multiflora rose in an effort to control erosion and provide cover and winter food for wildlife. Those hopeful ideas waned when the plant began to spread and became a serious invader of agricultural lands, pastures, and native ecosystems throughout the eastern United States. Now, it is considered an invasive plant; in 1983, the state of Missouri declared it a noxious weed.
The great majority of plants develop from seeds that fall to the soil nearby the parent plants. Birds and mammals, however, eat the rose hips and can disperse the seeds over greater distances. The seeds may remain viable in the soil for 10–20 years. This plant also spreads by “layering,” which is when new plants arise at the places where the tips of canes touch the ground and put out roots.
People brought this plant to America as an ornamental, then planted it widely, hoping it would have a beneficial effect on the environment. Time, however, has taught us that the negative effects outweigh the positive ones. Many invasive plants do not initially display signs of invasiveness. This plant has taught land managers a hard lesson about hindsight.
Multiflora rose invades prairies, savannas, open woodlands, and forest edges. A thorny, bushy shrub that forms impenetrable thickets, it smothers out other vegetation. Although it provides some benefits for wildlife, the way it degrades our natural communities is worse.
There are no sharp dividing lines between trees, shrubs, and woody vines, or even between woody and nonwoody plants. “Wood” is a type of tissue made of cellulose and lignin that many plants develop as they mature — whether they are “woody” or not. Trees are woody plants over 13 feet tall with a single trunk. Shrubs are less than 13 feet tall, with multiple stems. Vines require support or else sprawl over the ground.