KING COUNTY NOXIOUS WEED CONTROL PROGRAM WEED ALERT field 5'ndweed (aka Morning Glory) Convolvulus arvensis Morninqqlory Family Non-Designated Noxious Weed: Control Recommended Identification Tips > Deep rooted perennial vine that grows along the ground until it comes in contact with other plants or structures; then climbs aggressively > Smooth, arrowhead-shaped leaves > Slender, twining stems that can grow to 6 feet long > Trumpet-shaped flowers, light pink to white > Two small leaf bracts about one inch below the flower > Fleshy pale roots that travel deeply and widely Biology > Reproduces vegetatively from roots, rhizomes, stem fragments and by seeds that can lie dormant in the soil for up to 20 or more years > Roots spread widely underground, both vertically and horizontally, forming dense mats > Flowering is indeterminate, so flowers continue to develop along stems until the first frost Impacts > Once established, nearly impossible to fully eradicate > Out-competes native plant species > Dense infestations can reduce crop yields by up to 60% > Threatens restoration efforts by out-competing new plantings Distribution > Found in ravines, greenbelts, forested parks and farmlands as well as residential settings such as flower gardens, rockeries and ornamental borders > Can grow in a wide range of conditions from full sun to full shade and is drought-tolerant Questions? - King County Noxious Weed Control Program Line: 206-477-WEED www.kingcounty.gov/weeds Often called "Morning Glory,"field bindweed is an aggressive, invasive perennial plant found throughout the West. Field bindweed starts out growing along the ground until it finds plants, fences or other stuctures to climb up on. yjj King County What You Can Do While there is no legal requirement for controlling field bindweed in King County, the King County Noxious Weed Control Board recognizes this plant as invasive and is collecting information and providing education on control. The Board encourages and recommends control of existing populations especially in farming areas, natural lands and forests. Control Methods For best results, control methods should be used throughout several growing seasons; success in controlling this weed requires the prevention of seeds, competition from more desirable vegetation and vigilance in removing new growth. Prevention: Remove seedlings before they become perennial plants and produce seeds. Don’t dispose in backyard compost piles; bindweed can resprout from cuttings (okay to put into city provided yard recycling bins as the waste is taken to a commercial composting operation). Manual: Avoid digging or tilling the soil around mature field bindweed roots; roots or rhizome fragments left behind may resprout. Repeated hand pulling works eventually, but is highly labor intensive. It is best to limit hand pulling and tilling to seedlings; do in early spring when the ground is wet. Smothering plants with mulch, black plastic or plastic-fiber mats (geotextiles) is another option, but the covering must be kept in place for several years. Success may be somewhat limited as field bindweed can persist without light, sending its underground roots beyond the edge of the covering to start a new infestation. If using coverings, check often for cracks or openings; pull or spot spray any new growth coming up through the covering. Mechanical: Cutting alone will not control this plant and is not recommended. Chemical: Systemic (translocated) herbicides can be effective on bindweed, especially if combined with monitoring for surviving plants. Choose a formulation that is appropriate for the site: either aquatic or terrestrial. Follow the label exactly as written and only use at the rate that is prescribed on the label. Herbicides can be painted or brushed on leaves to avoid drift onto desirable plants. Products containing glyphosate are effective when applied in the summer and fall before the leaves die back. However, glyphosate is “non-selective” and will injure any foliage that it comes in contact with including grass. Selective broadleaf herbicides with the active ingredients triclopyr and 2,4-D work well for lawn areas as they won’t harm most grasses. Repeat on regrowth as needed. All these herbicides are absorbed by foliage and moved throughout the plant to kill the roots and shoots. If retreating with glyphosate in the same season, allow plants to grow and produce flowers before each application. Any questions, please contact the Noxious Weed Control Program. Also Vs/anteJ: Hejge BintlweeJ Hedge bindweed (Calystegia sepium ) looks very similar to field bindweed, but its flowers and foliage are larger. Additionally, the leaves are hairless and have a more pronounced arrow shape. They share the same invasive nature and both types of bindweed should be controlled whenever possible. Hedge bindweed doesn’t have the same deep root system, so hand pulling small sites is feasible. It also can be controlled with the same herbicides as field bindweed. kingcounty.gov/weeds - 206-477-WEED (206-477-9333) or TTY: 711 - noxious.weeds@kingcounty.gov Revised September 2007