While a vigorously growing rose bush sounds like a gardener’s dream, multiflora rose is the type of rose that you don’t ever want in your yard because it is highly invasive. The plant, which is native to Asia, forms large, dense thickets, chocking out native plants and disrupting ecosystems.
Multiflora rose spreads aggressively from its roots, stems, and the huge number of its seeds, which can remain viable in the soil for up to 20 years. If the invasive potential of multiflora rose wasn’t enough of a problem, it is also a primary host of rose rosette disease, which can be transmitted to other roses and for which there is no treatment.
If you find a multiflora rose in your yard, remove it as quickly as possibly because the longer you wait, the more difficult it will be to eradicate it. Here's how to identify and remove multiflora rose.
|Common Name||Multiflora rose|
|Botanical Name||Rosa multiflora|
|Mature Size||10-15 ft. tall, 9-13 ft. wide|
|Soil Type||Moist, well-drained|
|Bloom Time||Spring, summer|
|Hardiness Zones||5-9 (USDA)|
Multiflora Rose Invasiveness
Multiflora rose is currently found in 44 U.S. states and either classified as a noxious weed, prohibited invasive species, or banned for sale in a dozen states. It invades all types of habitats, from open woodlands and forest edges to wetlands, pastures, fields, roadsides, and the margins of swamps and marshes. Its fast and aggressive growth is a threat to native plants, thus impacting biodiversity.
Originally introduced in the United States in 1866 as a rootstock for ornamental roses, at one time before its destructive invasiveness was appreciated, multiflora rose had been widely used as an ornamental, for erosion control, and as a living fence for livestock enclosures.
The fact that multiflora rose spreads in several ways has made it one of the most dreaded invasive plants in the northeastern United States. It spreads from its wide root system and resprouts easily after being cut down. When the tips of its long, arching canes have contact with the soil, they take root and form new plants.
Multiflora rose produces a large amount of seeds, up to 17,500 seeds in a single cane, which on average adds up to 1 million seeds per plant. Up to 90% of the seeds are viable, and the seeds can remain viable in the soil for up to 20 years. If a multiflora rose pops up in your yard, it was most likely brought there by bird droppings. Birds like to eat the rose hips and disperse the seeds via their droppings.
Except for being a host for rose rosette disease, multiflora rose tolerates many other pests and diseases affecting roses. The only thing that puts a damper on its aggressive growth and spread is cold weather—multiflora rose is only moderately winter-hardy and does not survive at temperatures below 28 degrees Fahrenheit.
What Does Multiflora Rose Look Like?
Multiflora rose has stems, or canes, that can reach up to 15 feet in length. They are arching and root when the tips touch the soil, but they can also grow upright and climb into trees. In the first year or two, the plant grows rather slowly, only to take off vigorously afterwards.
The round stems are covered with hard, recurved thorns. The color is a vibrant olive green year-round, which distinguishes multiflora rose from native roses, raspberries, and blackberries, whose stems are reddish-maroon.
The leaves are alternate and pinnately compound with five to eleven oval serrated leaflets. A distinguishing characteristic of multiflora rose is a fringed base, or stipule, where the leaf connects to the stem. The upside of the leaves is smooth, and the underside is paler and hairy.
In May and June, the stems are covered with clusters of white or pale pink fragrant blossoms. The flowers have five petals and bright yellow pollen. In mid-summer, the spent flowers turn into small, shiny red rose hips. These later become darker and leathery yet remain on the plant through the winter and into the next growing season, another distinguishing characteristic of multiflora rose.
How to Get Rid of Multiflora Rose
The challenge of fully eradicating multiflora rose increases with the scope of the infestation. While it is possible to pull small plants by (a thick-gloved) hand—make sure to remove it with the entire root system to prevent resprouting)—large thickets require a combination of mechanical and chemical removal, as well as persistence.
First, cut the plants down to the ground, or mow them three to six times during the growing season to weaken them. This also gives you easier access for the following herbicide application. If the shrub consists of a few thick stems, cut them down to the ground with pruners and immediately brush the cut surfaces with glyphosate or triclopyr concentrate. If you are dealing with a widespread infestation and many small canes, let the plants regrow to about knee-level height. Then, on a calm, windless day, spray them with a broad-spectrum herbicide such as glyphosate or triclopyr, mixed with water according to the label directions. Because the second method is less targeted than the cut stem treatment, there is the risk of herbicide drifting on other plants nearby so use extreme caution.
Because of the long viability of the seeds in the soil, multiflora rose tends to re-emerge so you need to keep an eye on the location and retreat it in the following years as needed.
Is multiflora rose the same as wild rose?
Multiflora rose is not a wild native rose, it is an introduced species from Asia that has escaped cultivation and become invasive.
How can I distinguish a multiflora rose from a native rose?
Most native wild roses, such as prairie rose (R. arkansana), meadow rose (R. blanda), Carolina rose (R. caroliniana), swamp rose (R. palustris), and climbing wild rose (R. setigera). have pink flowers, whereas the flowers of multiflora rose are white. Multiflora rose has a green fringe at the base of the leaf.
Do birds eat multiflora rose?
Birds love to eat the hips with the seeds, thereby contributing to the spread of multiflora rose. Native roses are better plants to feed the birds and they don’t have the same noxious effects on the ecosystem.
Rosa multiflora. USDA Fire Effects Information System (FEIS).
Multiflora Rose. Brandeis University.
Multiflora Rose. New York Invasive Species Information.
Multiflora Rose. Penn State Extension.
Effective Spring Management of Multiflora Rose | Integrated Crop Management. Iowa State