Multiflora rose (Rosa multiflora)

Berries and leaves of Amur cork tree

 
 

Multiflora rose is a large multi-stemmed shrub 8-13 feet tall and 9-13 feet wide. Plants have white flowers and the stems often have an arching or drooping appearance. Multiflora rose forms dense thickets that reduce populations of native plants and reduce grazing quality in pastures.

Caution: Multiflora rose has thorns.

Description

Appearance

Multiflora rose is a dense multi-stemmed shrub that can reach 8-13 feet tall and 9-13 feet wide. Plants have white flowers and the stems often have an arching or drooping appearance.

Leaves and Stem

Multiflora rose leaves are alternate (come off the stem one at time at each leaf node). Leaves have leaflets that come off the leaf stalk opposite one another and then have a final leaflet at the tip of the leaf stalk (pinnately compound leaves). Leaflets have serrated edges. Each leaf usually has 7 or 9 leaflets but it can range from 5-11 leaflets. Individual leaflets are 1-2 inches long and the full leaf can be 4-6 inches long. At the base of each leaf where it meets the stem is a "stipule" which is a small green growth along the base of the leaf stalk. Multiflora rose stipules have fringes extending out along their edges and have visible glands that look like small dots. Native roses have smooth stipules with no fringe. Multiflora rose has thick curved thorns on the stems while native roses have thinner, straighter thorns.

Flowers

Multiflora rose flowers have white to slightly pink petals and are 1-2 inches wide. Flowers have five petals. Each petal has a notch in it, giving the petal a heart-like appearance. Flowers bloom in May and June. Native roses have pink flowers (some are very light pink).

Seeds

Multiflora rose produces small (diameter less than 0.25 inch) red to brownish-red fruit (rose hips) that contain the seeds. A plant can produce up to 500,000 seeds per year. Fruits can be eaten and spread by birds and wildlife. Seeds in the soil can remain viable for 10-20 years.

Roots

Multiflora rose has fibrous roots. Additionally, when multiflora rose stems arch over and touch the ground, they can send out roots from that spot and form another plant. In this way, a single initial plant can form a large dense patch in one spot.

Biology

Multiflora rose is a perennial shrub that can grow to 13 feet tall and 13 feet wide. It reproduces by seeds which can be spread to new sites. Within a site, an individual plant can spread vegetatively when its stems arch over, touch the ground, send out roots, and start a new plant. Multiflora rose is found in forest edges, woodlands, oak savannas, prairies, fields, pastures, and roadsides.

Origin and Spread

Multiflora rose is native to eastern Asia. It was brought to the United States from Japan in 1866 for rootstock for ornamental roses. Starting in the 1930s multiflora rose was widely planted in the United States for erosion control, wildlife, and ornamental purposes. Multiflora rose is widespread in the northeastern United States and is also present in the southeastern and western United States. In Minnesota, multiflora rose is mainly in southeastern Minnesota.

Refer to EDDMapS Distribution Maps for current distribution.

Don't be fooled by these look-alikes

  • Native roses such as smooth wild rose, Rosa blanda and prairie rose, Rosa arkansana – Native roses have pink flowers while multiflora rose has white flowers. Roses have a "stipule" which is a small green growth along the base of the leaf stalk. Multiflora rose has fringes extending out along the edges of the stipule. Native roses have stipules with smooth edges and no fringe. Multiflora rose has thick curved thorns on the stems while native roses have thinner, straighter thorns.
  • Common elderberry, Sambucus canadensis (native) – Common elderberry is a large shrub with white flowers, but it has small white flowers (1/4 inch across), has no thorns, and has small, black berries.
  • Prickly ash, Zanthoxylum americanum (native) – Prickly ash has compound leaves (divided into 5-11 leaflets), but its leaflets have smooth edges while multiflora leaflets have toothed edges.
 
Regulatory Classification

Multiflora rose is a Minnesota Department of Agriculture Restricted Noxious Weed meaning it is illegal to import, sell, or transport.

Threat to Minnesota
  • Multiflora rose forms dense thickets in forest edges, woodlands, oak savannas, prairies, fields, pastures, and roadsides. The thickets are painful to walk through and reduce populations of native plants.
  • It reduces grazing quality by invading pastures and grazing lands.
What you should do

One way that invasive plant seeds and fragments can spread is in soil. Sometimes plants are planted purposefully. You can prevent the spread of invasive plants.

PlayCleanGo: Stop Invasive Species in Your Tracks

  • REMOVE plants, animals & mud from boots, gear, pets & vehicle.
  • CLEAN your gear before entering & leaving the recreation site.
  • STAY on designated roads & trails.
  • PLANT non-invasive species.
Native Substitutes
 
Control Methods

Mechanical control can be done by pulling seedlings in small infestations when soil is moist. Due to the thorns on multiflora rose, care must be taken with manual removal if you choose to pull or dig up plants so you do not injure yourself on the thorns. Review Minnesota Department of Agriculture disposal information for noxious weeds. Cutting or mowing plants three to six times a year over two to four years can reduce the number of plants. Prescribed burning in the spring will kill seedlings and small plants, but mature shrubs may resprout. Repeated burns may be needed to control infestations. Contact University of Minnesota Extension for advice related to pasture management and grazing.

Herbicide control can be done using systemic herbicides which are taken up by plants and move within the plant, which can kill leaves, stems, and roots. Immediately after cutting (within 2 hours), apply an herbicide containing triclopyr (Garlon 3A/Vastlan, Garlon 4, or other brush killers with triclopyr) or glyphosate (Roundup) to the cut stump to prevent re-sprouting. Always follow label instructions for herbicides. Herbicides can be applied to cut stumps with a paintbrush, wick applicator such as a dauber or "buckthorn blaster," or a low volume sprayer. In cases where more than a few plants are treated, add an indicator dye (available where pesticides are sold), such as Mark-It Blue, to the herbicide to mark which cut stumps you have sprayed. July through October is the most effective time for cut-stem herbicide treatments.

Biological control is not available for multiflora rose although there are a number of species that damage multiflora rose that are either native to the United States or have been accidently introduced to the United States. For example, rose rosette disease is a native virus that is spread by an eriophyid mite (Phyllocoptes frutiphilus) and can be fatal to multiflora rose. However, it can also infect other members of the rose family such as native roses and plums, apples, and ornamental roses.

Reporting

Report new occurrences by submitting a report through EDDMapS Midwest, emailing Arrest The Pest, calling Arrest the Pest (1-888-545-6684), or contacting your local county agricultural inspector.

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