Report #1608 - Report: Meadow Knapweed (Centaurea × moncktonii)

Meadow Knapweed (Centaurea × moncktonii) on May 13, 2015

Submitter has sample
EDRR Status: Local expert notified

Description of specimen

Perennial Alternate stem leaves, petioled with attenuate base, acute tip, entire margin. Leaves reducing in size up the stem. Flowers lavender, approx 5 cm diameter; ray flowers showy; involucral bracts fringed. Some inflorescences from prior year still visible in spring 2015.

Commentary

Let me know if the images don't come through. I don't see how the above captures it.

Yamhill Co. will soon be adding asphalt to road. They are marking road now. On May 12, 2015 they mowed the roadside, so there likely are no plants to see. I Crossbowed the visible plants at the end of April, and hit some I missed with Roundup on May 10. I also sprayed those on north side of Rd on May 10. I have great concern that the county will scrape the road and dispose of the soil somewhere that the seeds will spread or push them onto private land.

Reporter
May 13, 2015, 2:58 p.m.

Thanks! Your photos came through just fine! As with your other reports, this invasive will be discussed at the Yamhill County Public Works Technical Advisory Committee meeting on May 21, 2015 and will be the subject of Best Management Practice being developed for roadside rights of way. The Yamhill SWCD is involved in that effort. Vern Holm Coordinator Western Invasives Network 971-241-2173 weeds@cascadepacific.org

Lindsey Wise
June 1, 2015, 2:23 a.m.

Location

Map shows GPSd (27 ft. accuracy) east end of meadow knapweed on south side of Kramien Rd, Newberg, Yamhill Co.OR. at short H-brace and a leaning dead snag. West end of knapweed is at 45.27499; -122.87854046 (21 ft. accuracy) at driveway of 34950 Kramien Rd. Roadside weed vegetation: mostly grass, Lactuca spp., shining geranium, Canada & bull thistle adjacent to overgrazed llama pasture continuing past pasture beside mixed Douglas fir/big-leafed maple. On the west end of this population it also occurs on the north side of Kramien, especially at the intersection with Rising Star Ln. Kramien Road is used by trucks hauling hay for horses, cows, and hay from eastern OR for resale. First seen in 2012 or 2013 (in flower). Population (incl. seedlings) was sprayed with Crossbow and Roundup in 2015.

Meadow Knapweed (Centaurea × moncktonii) on May 13, 2015

Description of specimen

Commentary

Resources

Location

Expert Reviewer