Eddmaps logo

Status of Invasive Plants in Oregon

Total number of exotic species reported: 599

Total number of records in EDDMapS: 243346


Invasive Plants by Category

  • Aquatic - 14 species, 5772 records
  • Conifer Trees - 1 species, 1 records
  • Forbs/Herbs - 373 species, 140891 records
  • Grass or Grasslike - 109 species, 14728 records
  • Hardwood Trees - 33 species, 926 records
  • Shrub or Subshrub - 38 species, 41149 records
  • Vines - 28 species, 4493 records

Top Ten Abundant Invasive Plants (by number of reports)

  1. Canada thistle - 23546 reports
  2. Scotch broom - 22160 reports
  3. common St. Johnswort - 18208 reports
  4. bull thistle - 16532 reports
  5. Himalayan blackberry - 16048 reports
  6. yellow starthistle - 11603 reports
  7. rush skeletonweed - 8447 reports
  8. diffuse knapweed - 6848 reports
  9. Dalmatian toadflax - 6435 reports
  10. perennial false-brome - 6198 reports

Top Ten Widespread Invasive Plants (by number of positive counties)

  1. Canada thistle - 36/36 (100%)
  2. bull thistle - 36/36 (100%)
  3. redstem filaree - 36/36 (100%)
  4. curly dock - 35/36 (97%)
  5. curly dock - 35/36 (97%)
  6. common yarrow - 35/36 (97%)
  7. common St. Johnswort - 35/36 (97%)
  8. orchardgrass - 35/36 (97%)
  9. soft brome - 35/36 (97%)
  10. soft brome - 35/36 (97%)

Counties with the most invasive species reported

  1. Lake County - 440 species
  2. Multnomah County - 423 species
  3. Lane County - 404 species
  4. Jackson County - 381 species
  5. Marion County - 380 species
  6. Benton County - 368 species
  7. Douglas County - 356 species
  8. Curry County - 312 species
  9. Umatilla County - 289 species
  10. Josephine County - 287 species

Counties with the least invasive species reported

  1. Gilliam County - 126 species
  2. Columbia County - 157 species
  3. Wheeler County - 162 species
  4. Sherman County - 166 species
  5. Tillamook County - 183 species
  6. Deschutes County - 184 species
  7. Crook County - 186 species
  8. Morrow County - 195 species
  9. Baker County - 196 species
  10. Clatsop County - 203 species

Report created on August 30, 2015 at 09:59 AM by the UGA Center for Invasive Species and Ecosystem Health using EDDMapS Technology and Data.