Prohibited Noxious Weeds

The following plants are designated as Prohibited-Noxious weeds in Alberta. Complete eradication is required. (All plants listed in Bold have been found within the County of Grande Prairie).  For detailed information on the weeds listed below, visit Alberta Invasive Species Council's Fact Sheets.

  • Autumn Olive
  • Barberry, common
  • Buckthorn, common
  • Crupina, common
  • Eurasian Water Milfoil
  • Garlic Mustard
  • Hawkweed, meadow
  • Hawkweed, orange
  • Hogweed, giant
  • Knapweed, bighead
  • Knapweed, brown
  • Knapweed, hybrid
  • Knapweed, Russian
  • Knapweed, squarrose
  • Knotweed, giant
  • Loosestrife, purple
  • Nutsedge, yellow
  • Ragwort, tansy
  • Saltlover
  • Starthistle, yellow
  • Tamarisk, smallflower
  • Thistle, nodding
  • Balsam, Himalayan
  • Bartsia, red
  • Cinquefoil, sulphur
  • Dyer's Woad
  • Flowering Rush
  • Goatgrass, jointed
  • Hawkweed, mouse-ear
  • Hoary Alyssum
  • Iris, yellow flag (pale yellow)
  • Knapweed, black
  • Knapweed, diffuse
  • Knapweed, meadow
  • Knapweed, spotted
  • Knapweed, Tyrol
  • Knotweed, Japanese
  • Medusahead
  • Puncturevine
  • Salt Cedar
  • St. John's-wort, Chinese
  • Tamarisk, Chinese
  • Thistle, marsh
  • Thistle, plumeless