Agriculture, Dept. of

General Agency, Board or Commission Rules

Chapter 63: Prohibited, Restricted, and Regulated Noxious Weed Seed List

Effective Date: 04/17/2024 to Current

Rule Type: Current Rules & Regulations

Reference Number: 010.0005.63.04172024

Chapter 63

Prohibited, Restricted, and Regulated Noxious Weed Seed Lists

Section 1. Authority. Pursuant to Wyoming Statute § 11-12-104(a), the Department of Agriculture promulgates these regulations.

Section 2. Definitions.

1. (a) “Large seeded crops” means crops with seeds the size of winter wheat or larger.
2. (b) “Small seeded crops” means crops with seeds smaller than winter wheat.

Section 3. Prohibited Noxious Weeds. The noxious weeds listed in this section are established as prohibited noxious weeds.

Amaranth, Palmer	Amaranthus palmeri
Bindweed, field	Convolvulus arvensis L.
Blueweed	Echium vulgare L.
Burdock, common	Arctium minus (Hill) Bernh.
Bursage, skeletonleaf	Ambrosia tomentosa Nutt.
Camelthorn	Alhagi maurorum Medik.
Campion, bladder	Silene vulgaris (Moench) Garcke subsp. vulgaris
Crupina common	Crupina vulgaris Cass.
Daisy, oxeye	Leucanthemum vulgare Lam.
Dodder	Cuscuta spp.
Goatgrass, jointed	Aegilops cylindrical Host
Halogeton	Halogeton glomeratus (M. Bieb.) Ledeb.
Hawkweed, orange	Hieracium aurantiacum L.
Hemlock, poison	Conium maculatum L.
Henbane, black	Hyoscyamus niger L.
Hound’s tongue	Cynoglossum officinale L.
Knapweed, black	Centaurea nigra L.
Knapweed, diffuse	Centaurea diffusa Lam.
Knapweed, meadow	Centaurea x moncktonii C. E. Britton
Knapweed, Russian	Rhaponticum repens L. Hidalgo
Knapweed, spotted	Centaurea stoebe subsp. micranthos (Gugler) Hayek
Knapweed, squarose	Centaurea squarrosa Willd.
Loosestrife, purple	Lythrum salicaria L.
Medusa-head	Taeniatherum caput-medusae (L.) Nevski subsp. caput-medusae
Millet, wild proso	Panicum milliaceum L. subsp. ruderale (Kitag.) Tzvelev
Olive, Russian	Elaeagnus angustifolia L.
Pepperweed, perennial	Lepidium latifolium L.

Puncturevine	Tribulus terrestris L.
Quackgrass	Elymus repens L. Desv. ex Nevski
Saltcedar	Tamarix spp.
Salvation jane	Echium plantagineum L.
Sandbur, field	Cenchrus incertus M. A. Curtis
Sandbur, longspine (mat)	Cenchrus longispinus (Hack.) Fernald
Skeletonweed, rush	Chondrilla juncea L.
Sowthistle, perennial	Sonchus arvensis L.
Spurge, leafy	Euphorbia esula L.
Starthistle, purple	Centaurea calcitrapa L.
Starthistle, yellow	Centaurea solstitialis L.
St. Johnswort	Hypericum perforatum L.
Swainsonpea	Sphaerophysa salsula (Pall) DC.
Tansy, common	Tanacetum vulgare
Thistle, Canada	Cirsium arvense (L.) Scop.
Thistle, musk	Carduus nutans L.
Thistle, plumeless	Carduus acanthoides L.
Thistle, Scotch	Onopordum acanthium L.
Toadflax, Dalmatian	Linaria dalmatica (L.) Mill.
Toadflax, yellow	Linaria vulgaris Mill.
Tussock, serrated	Nassella trichotoma (Nees) Hack. ex Arechav.
Whitetop	Lepidium draba L.
Woad, dyers	Isatis tinctoria L.

Section 4. Restricted Noxious Weeds. The noxious weeds listed in this section are established as restricted noxious weeds. The tolerance for restricted noxious weeds, unless otherwise stated, shall be 50 seeds per pound in small seeded crops and five seeds per pound in large seeded crops.

Cinquefoil, sulphur	Potentilla recta L. ‘Warrenii’
Dock, curly	Rumex crispus L.
Knotweed, Japanese	Fallopia japonica (Houtt.) Ronse Decr.
Lettuce, blue	Lactuca tatarica subsp. pulchella (Pursh) Stebbins
Licorice, wild	Glycyrrhiza lepidota Pursh
Mallow, Venice	Hibiscus trionum L.
Mustard, wild	Sinapis arvensis L. subsp. arvensis
Oat, wild	Avena fatua L.
Plantain, buckhorn	Plantago lanceolata L.
Povertyweed	Iva axillaris Pursh
Ragweed, perennial	Ambrosia psilostachya DC.

Section 5. Regulated Weeds. The noxious weeds listed in this section are established as regulated noxious weeds. The tolerance for regulated noxious weeds is specified for each species as shown below.

1. (a) Cheat Bromus secalinus L. – Tolerance shall be 1,200 seeds per pound.
2. (b) Downy brome Bromus tectorum L. – Tolerance shall be 1,200 seeds per pound.
3. (c) Feral rye Secale cereale L. subsp. cereale – Tolerance shall be none in small grains other than rye.
4. (d) Japanese brome Bromus japonicus Thunb. – Tolerance shall be 1,200 seeds per pound.
5. (e) Ripgut brome Bromus diandrus Roth var. rigidus (Roth) Sales – Tolerance shall be 1,200 seeds per pound.
6. (f) Ventenata Grass Ventenata dubia - Tolerance shall be 1,200 seeds per pound.