There are a wide variety of non-native invasive plant species that have taken hold in Madison County. These plants cause harm to the environment, as well as potential harm to human, animal, and plant health in the preexisting environment. Some of these damages can be caused by overtaking beneficial native plants in the ecosystem, act as vectors for diseases and other invasive species, such as invasive insects, and are unhealthy or potentially toxic to native animals. In this series, we will discuss identification and control of these prevalent invasive plants.

Identifying Multiflora Rose

Multiflora rose (rosa multiflora) is a deciduous shrub in the Rosaceae family, which includes well-known plants such as ornamental roses, almonds, peaches, apples, pears, blackberries, and many more. This invasive plant originated in Asia (Japan, China, and Korea), and was introduced to the United States in the 1860s. Multiflora roses can grow up to ten feet tall, and have arching stems covered in curved, hooking thorns. The stems contain compound leaves, which consist of anywhere from 5 to 11 leaflets alternately arranged on the stem with a terminal leaf at the very tip of the leaf stem. Every leaflet is oval in shape with serrated edges, and at the bottom of every leaf (containing all of the leaflets) a hairy or feathery, flat structure called a stipule can be seen on this particular species. Multiflora roses also produce a small red fruit called “rose hips” that develop during the summer and can persist on the stems into the winter.  Flowers bloom from May to June, and are 5-petaled, white to pinkish in color, and appear in clusters. You can identify multiflora roses compared to other shrub-like roses due to the arching stems, curved thorns, and the hairy or feathery stipule.

How It Spreads

As mentioned earlier, multiflora rose was introduced to the United States in the 1860s as rootstock for many ornamental roses, and was originally thought to support and attract wildlife populations. It was later planted in an attempt to help control erosion, as well as to be used as a “living fence” to help contain livestock. It was even used in select states on roadsides to create crash barriers and to help disrupt bright headlights shining from oncoming vehicles. These intended uses have pushed the presence of multiflora roses all across the state of North Carolina. Multiflora rose produces a massive amount of seeds, 500,000 to 1,000,000 seeds from an average sized shrub, in a single year. This fact, coupled with the dispersal of seeds by birds, and the ability for this invasive to root at the tips of its arching branches, makes it a serious threat to a variety of natural areas. It can thrive in a wide variety of conditions, including varying light, soil types, and levels of moisture. Multiflora rose is also a fierce competitor against native shrubs and underbrush due to its ability to leaf out earlier in the spring than many native plants, helping to choke out many of the native underbrush species in the areas it infests. Areas that are in danger of invasion from this invasive species are roadsides, pastures, wetlands such as mountain bogs, and other non-forested sites. Any disturbed right of ways can leave an ideal opening for the spread of multiflora roses.

Controlling Multiflora Rose

As discussed previously, the massive amount of seeds produced by multiflora roses contributes widely to the spread of this invasive species throughout Madison County and through many other areas across the state. Methods like cutting or mowing multiflora roses at least once during the growing season can help control the spread of this invasive plant species, but it will not completely eradicate its presence. Small, sprouting plants can be dug free from the soil by hand, and if you have large plants present, you can pull them from the ground using chains or strong ropes, and heavy machinery such as a tractor or a truck.

If dealing with a large infestation of multiflora roses, or if the plants are located in an unsafe or undesirable area to pull plants up, then chemical control can be a viable option. There are several chemical control options available that are considered effective in controlling and even completely eliminating multiflora roses from pastures, landscapes, roadsides, and more. There are a few different forms of chemical control that can be used. The first are foliar treatments, which are effective when sprayed in the spring through the fall, using a selective woody herbicide, such as the active ingredient triclopyr, mixed in a 2% solution with 0.5% of non-ionic surfactant. If treating a large, heavily infested area, a mixture of 1 ounce of metsulfuron in 100 gallons of water in a large attachment sprayer on an ATV or tractor can treat an area roughly the size of an acre.

Another, more targeted option of chemical control is a method known as cut-stump. The cut-stump method can be used throughout the year as long as the ground is not frozen, and can help to protect areas where the multiflora rose may be surrounded by more desirable plants or native species that could be harmed from potential drift from a foliar application of herbicide. The most effective times of the year for cut-stump applications are through the summer and fall, as the multiflora rose is actively drawing nutrients back toward its root systems. To conduct this method, create a solution of 25% herbicide using the active ingredient triclopyr, and spray this solution on the stump that was just cut. Be sure that you are applying the herbicide solution on the stump as quickly as possible to the remaining stump to allow for the turgor pressure of the plant’s vascular system to absorb it into the root system. Turgor pressure is caused by the pressure of water within the plant cells that allows the plant to keep its upright and rigid structure, as well as aiding in the flow of nutrients across the expanse of the plant, from the tips of the leaves to the ends of the roots underground. Soak the entire surface of the stump in the herbicide solution until the stump is no longer actively absorbing the solution, which may begin to happen within 3 to 5 minutes of cutting the stump. No matter which form of treatment chosen, be sure to follow up with treatment again to control any new sprouts or potential return of the same plants.

If you have any other questions about identifying or controlling Multiflora roses, please contact the Madison County Cooperative Extension Center at peyton_duckett@ncsu.edu, or (828) 649-2411.

Citations

NC Forest Service, & NCDOT. (March 2010). Rosa multiflora (Multiflora Rose). Invasive Species Leaflet.

NC State Extension. (n.d.). Rosa multiflora. North Carolina Extension Gardener 

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