Multiflora Rose Control in Pastures

Multiflora rose has been a common topic of conversation among pasture-based livestock owners for as long as I can remember. Although considerable progress has been made in understanding and controlling it, one doesn't have to drive far around the countryside in Pennsylvania to see that there is still room for improvement. The spread of multiflora rose in Pennsylvania has led to its designation as a noxious weed in the state.

Control of this problem often involves an integrated approach. There are physical, biological, chemical, and cultural means of control. Multiflora can be controlled, but it takes considerable effort.

Begin by considering prevention and cultural aspects. All the things we normally discuss in the progressive management of pastures will help prevent multiflora from becoming established in the first place. Maintaining a suitable pH and fertility, planting adapted forage species, implementing rotational grazing, and leaving sufficient residual forage after grazing are all measures that can significantly reduce the likelihood of multiflora rose becoming established.

But what do we do if there is already an infestation of multiflora?

On the biological side, there have been some interesting developments. Probably the most promising of which was the arrival of rose rosette disease (RRD). RRD is a virus that is spread by mites. Within two years of infection with RRD, the entire multiflora rose plant will be dead. RRD has expanded across a significant portion of Pennsylvania over the past several years. In my region of the state, areas that once had severe infestations of multiflora rose are looking very different as RRD kills large stands of multiflora. When we first started hearing about RRD moving northward years ago, I actually had farmers asking if we could bring in mites from areas with RRD and release them to allow them to do their work in spreading RRD. A good indicator of how badly despised this weed is.

Another biological option is the inclusion of sheep and/or goats into the grazing system. It is no secret that goats enjoy browsing and will strip leaves and bark from multiflora bushes. In my experience, sheep will strip leaves and eat new growth that is within their reach. Ultimately, goats are probably more effective in eliminating multiflora rose. As a cattle owner, you may not have any interest in raising small ruminants, but there may be producers who would bring either of these species to your farm to help get rid of multiflora. A small ruminant owner can target specific areas on your farm by using portable net fencing to confine the goats/sheep to one location.

On the chemical side, there are several options to gain control. These treatments can be categorized into soil, foliar, thin-line, and basal bark treatments. Herbicides recommended for effective control of multiflora rose are 2,4-D, Banvel/Clarity (dicamba), Crossbow (2,4-D LVE + triclopyr), Roundup (glyphosate), Metsulfuron-methyl 60DF, and Spike 20P. The selection of which herbicide to use is based on several factors. For more information, consult the Penn State Agronomy Guide or Multiflora Rose Management in Grass Pastures. As always, consult the label before using any of these materials and pay particular attention to the grazing restrictions after use.

On the physical side, we can sometimes mow, dig, pull, or bulldoze multiflora to eradicate it. Repeated mowing can destroy the plant's ability to produce food. Research has shown that controlling multiflora with mowing requires 3-6 mowings over a period of more than one year. Another means of physical control is excavation, which involves digging or pulling the plants out of the soil. All roots with shoot buds need to be removed. Of course, the success of physical eradication depends on the size of the plants and the size of the infestation. Large plants and large infestations may require heavier equipment. Physical means of eradication can become expensive when attempted on a larger scale.

Finally, once you have gained control of multiflora rose on your farm, don't relinquish it. As mentioned earlier, a well-managed pasture and grazing system will generally not be overrun by multiflora. A well-managed pasture sward will be able to out-compete weed threats. The occasional multiflora plant may turn up underneath a fence, but it can be easily dealt with at that point.