Noxious Weeds - Designations

The weeds listed on the Statewide Prohibited Genera, EDRR, Containment, and Control lists are hereby officially designated and published as noxious. (3-15-22) 01. Statewide Prohibited Genera Noxious Weed List. (3-15-22) a. All plants and plant parts in the genera of: Cytisus, Genista, Spartium, and Chamaecytisus additionally including “all” subtaxa of these plant genera are prohibited in Idaho. (3-15-22) b. Weeds listed in the Prohibited Genera list may exist in varying populations throughout the state. The concentration of these weeds is at a level where control and/or eradication may be possible. A written plan for weeds on the Statewide Prohibited Genera Noxious Weed List shall be developed by the control authority that specifies active control methods to reduce known populations in not more than five (5) years. The plan shall be available to the Department upon request. (3-15-22) 02. Statewide EDRR Noxious Weed List. Weeds listed in the EDRR list are not known to exist in Idaho, however, have the potential to become established, or are known to exist in Idaho in small enough infestations that eradication is possible. If any of the listed plants (Subsection 220.02) are found to occur in Idaho, they shall be reported to the Department within ten (10) days following positive identification by the University of Idaho or other qualified authority as approved by the Director. These weeds shall be eradicated during the same growing season as identified. Common Name Scientific Name 1. Brazilian Elodea Egeria densa 2. Cogongrass Imperata cylindrica 3. Common/European Frogbit Hydrocharis morsus-ranae 4. Fanwort Cabomba caroliniana 5. Feathered Mosquito Fern Azolla pinnata 6. Giant Hogweed Heracleum mantegazzianum 7. Giant Salvinia Salvinia molesta 8. Goatsrue Galega officinalis 9. Hydrilla Hydrilla verticillata 10. Iberian Starthistle Centaurea iberica 11. Policeman’s Helmet Impatiens glandulifera 12. Purple Starthistle Centaurea calcitrapa 13. Squarrose Knapweed Centaurea triumfetti 14. Starry Stonewort Nitellopsis obtusa 15. Syrian Beancaper Zygophyllum fabago 16. Tall Hawkweed Hieracium piloselloides 17. Variable-Leaf-Milfoil Myriophyllum heterophyllum 18. Water Chestnut Trapa natans 19. Water Hyacinth Eichhornia crassipes 20. Yellow Devil Hawkweed Hieracium glomeratum 21. Yellow Floating Heart Nymphoides pelata (7-1-25) 03. Statewide Control Noxious Weed List. Weeds listed in the control list are known to exist in varying populations throughout the state. The concentration of these weeds is at a level where control or eradication, or both, may be possible. A written plan for weeds on the Statewide Control Noxious Weed List shall be developed by the control authority that specifies active control methods to reduce known populations in not more than five (5) years. The plan shall be available to the Department upon request. Common Name Scientific Name 1. Black Henbane Hyoscyamus niger 2. Bohemian Knotweed Polygonum X bohemicum 3. Common Crupina Crupina vulgaris 4. Common Reed (Phragmites) Phragmites australis 5. Dyer’s Woad Isatis tinctoria Myriophyllum spicatum 6. Eurasian Watermilfoil (and hybrids) 7. Flowering Rush Butomus umbellatus 8. Giant Knotweed Polygonum sachalinense 9. Japanese Knotweed Polygonum cuspidatum 10. Johnsongrass Sorghum halepense 11. Matgrass Nardus stricta 12. Meadow Knapweed Centaurea debeauxii 13. Mediterranean Sage Salvia aethiopis 14. Musk Thistle Carduus nutans 15. Orange Hawkweed Hieracium aurantiacum 16. Parrotfeather Milfoil Myriophyllum aquaticum 17. Perennial Sowthistle Sonchus arvensis 18. Russian Knapweed Acroptilon repens 19. Scotch Broom Cytisus scoparius 20. Small Bugloss Anchusa arvensis 21. Turkish Thistle Carduus cinereus 22. Vipers Bugloss Echium vulgare 23. Yellow Hawkweed Hieracium caespitosum (7-1-25) 04. Statewide Containment Noxious Weed List. Weeds listed in the containment noxious weeds list are known to exist in various populations throughout the state. Weed control efforts may be directed at reducing or eliminating new or expanding weed populations while known and established weed populations, as determined by the weed control authority, may be managed by any approved weed control methodology, as determined by the weed control authority. Common Name Scientific Name 1. Canada Thistle Cirsium arvense 2. Curlyleaf Pondweed Potamogeton crispus 3. Dalmatian Toadflax Linaria dalmatica ssp. dalmatica 4. Diffuse Knapweed Centaurea diffusa 5. Field Bindweed Convolvulus arvensis 6. Hoary Alyssum Berteroa incana 7. Houndstongue Cynoglossum officinale 8. Jointed Goatgrass Aegilops cylindrica 9. Leafy Spurge Euphorbia esula 10. Milium Milium vernale 11. Oxeye Daisy Leucanthemum vulgare 12. Perennial Pepperweed Lepidium latifolium 13. Plumeless Thistle Carduus acanthoides 14. Poison Hemlock Conium maculatum 15. Puncturevine Tribulus terrestris 16. Purple Loosestrife Lythrum salicaria 17. Rush Skeletonweed Chondrilla juncea 18. Saltcedar Tamarix spp. 19. Scotch Thistle Onopordum acanthium 20. Spotted Knapweed Centaurea stoebe 21. Tansy Ragwort Senecio jacobaea 22. White Bryony Bryonia alba 23. Whitetop (Hoary Cress) Cardaria draba 24. Yellow Flag Iris Iris pseudocorus 25. Yellow Starthistle Centaurea solstitialis 26. Yellow Toadflax Linaria vulgaris (3-15-22) 05. Designation of Articles Capable of Disseminating Noxious Weeds. The following articles are designated by the Director as capable of disseminating noxious weeds: (3-15-22) a. Construction equipment, road building and maintenance equipment, and implements of husbandry. (3-15-22) b. Motorized vehicles such as, all-terrain vehicles, motorcycles, and other off-road vehicles and non- motorized vehicles such as bicycles and trailers. (3-15-22) c. Grain and seed. (3-15-22) d. Hay, straw and other material of similar nature. (3-15-22) e. Nursery stock including plant material propagated for the support of aquarium, pet, or horticultural activities. (3-15-22) f. Feed and seed screenings. (3-15-22) g. Fence posts, fencing and railroad ties. (3-15-22) h. Sod. (3-15-22) i. Manure, fertilizers and material of similar nature. (3-15-22) j. Soil, sand, mulch, and gravel. (3-15-22) k. Boats, personal watercraft, watercraft trailers, and items of a similar nature. (3-15-22)