Family: Polygonaceae Cycle: Annual Plant Type: Broadleaf. It is an annual species that is native to Europe that has established itself throughout most of the United States and Canada. Prostrate knotweed is probably the earliest of the summer annuals to germinate in the spring. In particular, it has been used in conjunction with other long-term therapies. Knotweed, Prostrate knotweed: Family: Polygonaceae: USDA hardiness: 4-8: Known Hazards: Although no specific mention has been made for this species, there have been reports that some members of this genus can cause photosensitivity in susceptible people. Please login to view these details. All members of the Smartweed family have a distictive structure at the stem-branch junction called the ochrea (erect, below left; prostrate, below right). Habit. Damaged areas will often 'spontaneously recover' in the spring only to later turn out to be knotweed. Prostrate knotweed is a prostrate weed that produces a thin taproot and multiple branched stems. Prostrate Knotweed (A) (Polygonum aviculare) - family: Polygonaceae (Smartweed) - MSU Turf Weeds.net - Weed identification and information. KNOTWEEDS. Q4® Plus Turf Herbicide for Grassy & Broadleaf Weeds, SpeedZone® Southern Broadleaf Herbicide for Turf, Trimec® 1000 Low Odor Broadleaf Herbicide, Trimec® Bentgrass Formula Broadleaf Herbicide, Trimec® Southern Broadleaf Herbicide for Sensitive Southern Grasses, TZone SE Broadleaf Herbicide for Tough Weeds. Prostrate knotweed tolerates extremely compacted soils and … Biology. Knotweed family (Polygonaceae) Description:Thisplant is a more or less prostrate summer annual, producing hairlessstems up to 3' long. Prostrate, mat-forming summer annual. Prostrate Knotweed Polygonum aviculare is tough weed that grows well in heavily trafficked areas with compacted soils. Due to its early germination timing, knotweed is able to claim resources and invade damaged areas before other desirable grasses begin to grow. This plant often attracts predatory insects. Prostrate Spurge (Euphorbia maculate) Interesting Information About Plant: The Euphorbia maculata (spotted spurge) is a plant native to North America.The Prostrate Spurge, also commonly known as creeping spurge or spotted spurge, typically grows in the side walk cracks next to … introduced annual, reproducing by seed. mature plants. Identification Notes. Plants will form mats due to their growth habit. Ocrea is characteristic of plants in the buckwheat family. Common or prostrate knotweed, or Polygonum arenastrum, also known as wiregrass, wireweed, matweed or doorweed, grows flat, spreading outward in a dense circular form that can reach 18 inches across with a narrow taproot that can grow as deep. Click here for the mobile/phone version of this web site, Click here for the mobile version of this web site. Thank you! They are oblong or oblong-elliptic, smooth along the margins,and hairless. The flowers of knotweed are small pink to white and form in clusters in the leaf axis. Alternate, narrow oval to oblong leaves with pointed tips, smooth margins and short petioles. When knotweed germinates in March is often resembles grass and can offer some false hope that those damaged areas are spontaneously repairing themselves where the snowplow missed the sidewalk. Each plant is capable of producing thousands of seeds that stay viable for several years. Sixty-one species of insects have been observed feeding on prostrate knotweed (Wilson et al. The slender stems radiate from a central taproot and produce a tough mat-like growth. Spotted spurge also forms mats, however, the leaves, stems and roots of spotted spurge will exude a milky white latex when damaged. 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