Franklin County SCOURING RUSH Franklin County Noxious Noxious Weed EQUISETUM SSP. Weed Control Board Control Board

The FCWB educates property owners on identification, im- Visit our website! Options for Control pacts and control methods for state-listed noxious weeds and www.fcweedboard.com helps out with the identification and control options of the oc- casional nuisance weed. It is also our job to locate noxious weed infestations that are not being effectively controlled. To achieve this, the program con- ducts annual surveys and fol- low-up checks on existing nox- ious weed locations. Program staff provides the landowner with information on how to identify and control noxious weeds on their prop- erty. If requested, we will meet with the owner or prop- erty manager to review the weed locations and discuss site-specific noxious weed control plans. For more information, contact the FCWB at 509-545-3847 or [email protected]. Physical: 502 Boeing St. Mailing: 1016 N 4th Pasco, WA 99301 509-545-3847 [email protected] www.fcweedboard.com Scouring Rush items such as cooking pots or rhizomes, manual or mechanical control should be drinking mugs. In Japan field done as soon after emergence as possible. horsetail (E. hymale) is still Because of it’s hard, waxy cuticle, high silica content, Scouring rush (Equisetum hyemale) is a nuisance boiled and then dried to be used for final polishing on and aggressive rhizomes, horsetail is very difficult to plant invading landscaping, yards, irrigated ditches, control with herbicides. Herbicide applications are and irrigated farmland in Franklin County. Scour- wood to produce a smoother finish than any sandpaper. most effective when plants are 6 inches tall or less. It ing rush belongs to one of the oldest plant families, is best to use a surfactant along with the herbicide for Equisetaceae, which is over 100 million years old. If eaten over a long period of best results. Equisetaceae are vascular plants which reproduce by time some species can be spores, not seeds. poisonous to grazing animals, For the Homeowner: Spot treatment applications including horses. with glyphosate can be used, though one should ex- Scouring rush is a perennial plant which has vertical pect that re-treatment will be necessary. Glyphosate, jointed reed-like stalks of medium to dark green. however, reduces or removes competitive plants The hollow stems are up to 3 feet (0.91 m) in which reduces scouring rush infestations. height. The tiny leaves are joined together around the stem, forming a narrow black-green band or Control Options For Farm Application: Herbicides containing the ac- sheath at each joint. Like other ferns and their rela- tive ingredient halosulfuron-methyl (Sedgehammer, Sandea, etc.), chlorsulfuron (Telar), dichlobenil tives, the plant reproduces by spores. Scouring Rush is so invasive and difficult to control that it (Casaron) and MCPA are effective in the control or is very important to prevent it from becoming established. The stems are generally deciduous in cold climates, suppression of Scouring rush. These products are best and remain during winter in warmer climates. It Lasting control of horsetails is difficult to achieve because suited for large areas, agricultural and industrial uses forms dense spreading colonies, in full to partial of the high level of food reserves stored in the rhizome. and are not readily available for homeowner use. sun. The plant spreads very aggressively by under- Prevent spread and establishment of horsetails by using ground runners, reaching under/past pavements only clean soil in your landscape and by checking nursery READ AND FOLLOW ALL PESTICIDE LA- and garden walls. stock for unwanted plants. BEL DIRECTIONS AND RESTRICTIONS. Root barriers or BE SURE THAT PRODUCT USE IS COM- large sunken plant- Horsetail stems are without functional leaves, so they PATIBLE WITH YOUR GOALS. ers ease contain- don’t tolerate much shading. Densely plant areas with ment in the garden. horsetail to shade them out and reduce spore germination. Scouring Rush Use of landscape fabric can help horsetail from getting prefer wet sandy established in an area because germinating spores can’t soils, though some grow through the fabric. Covering an infested area with are semi-aquatic fabric can help suppress re-growth but, because of their and can withstand aggressive rhizomes, they often run to the edge of the periodic flooding. fabric and emerge there. Layers of bark mulch, sawdust, The stalks arise or other plant material will not control horsetail. from rhizomes that For established patches, efforts should be directed at de- are deep under- pleting the food reserves in the rhizomes. Complete re- ground and almost moval of the tops about 2 weeks after each emergence for impossible to dig out. Scouring rushes can be nui- 3 to 4 years has provided effective control. Tilling can sance weeds, readily regrowing from the rhizome make the problem worse by spreading the rhizomes into after being pulled out. new areas. In a study in Quebec, Canada, horsetail was The hollow stems are coated with abrasive silicates, removed by hoeing 16 times, but had no impact on re- making them useful for scouring (cleaning) metal growth. Removal of fertile stems as soon as they appear will help to reduce spread by spores. In order to deplete