Monthly Work Plan - Noxious Weeds

Each month we will provide a work plan for the noxious weeds that are active.

Common Teasel flowerheads.
Common mullein along a trail.
Canada thistle flower.
  1. Sept
  2. Oct
  3. Nov
  4. Dec
  5. Jan
  6. Feb
  7. Mar
  8. Apr
  9. May
  10. June
  11. July
  12. Aug

September 

Weed  StageAction Plant InfoNotes
Bull thistle
Flowering, dropping seedClip, bag, and put into trashBiennial
Taproot
Reproduces by seed
Next year plan on doing your removal in the spring and early summer before the flowerbuds form (when plants are less than 12 inches tall)
Bull thistleRosettesRemove or treat with herbicide

Canada thistle Dropping seed, Beginning to move resources to the rootsTreat plants with herbicidePerennial
Deep spreading roots
Reproduces by seed and spreading roots
Do NOT pull.  Pulling breaks the root and creates new plants.
The majority of the seeds are sterile.  Most seed drops near the mother plant
ChamomileOlder plants dropping seedRemove, bag, put into trashPerennial
Fibrous roots
Reproduces by seed

ChamomileSeedlingsRemove or treat with herbicidePerennial
Fibrous roots
 Reproduces by seed

CheatgrassRegrowthTreat site with pre-emergent herbicide - see Fact sheet for detailsAnnual (Winter annual)
Fibrous roots
Reproduces by seed

Common mulleinOlder plants dropping seedRemove, bag, put into trashBiennial
Taproot
Reproduces by seed
Next year plan on doing your removal in the spring and early summer before the flowerbuds form (when plants are less than 12 inches tall)
Common mulleinRosettesRemove or treat with herbicide

Dalmatian toadflaxAll stagesTreat plants with herbicidePerennial
Deep taproot with spreading roots
Reproduces by seed and spreading roots
Do NOT pull.  Pulling breaks the root and creates new plants.
Diffuse knapweedOlder plants dropping seedRemove, bag, put into trashBiennial
Taproot
Reproduces by seed
Next year plan on doing your removal in the spring and early summer before the flowerbuds form (when plants are less than 12 inches tall)
Diffuse knapweedNew rosettesRemove or treat with herbicide

Hairy willowherbDropping seedTreat plants with herbicidePerennial
Spreading roots
Reproduces by seed and spreading roots

Hoary cressPre-growthTreat site with pre-emergent herbicide - see Fact sheet for detailsPerennial
Spreading roots
Reproduces by seed and spreading roots

HoundstoungeNew rosettesRemove or treat with herbicideBiennial
Taproot
Reproduces by seed

KnotweedDropping seedTreat plants with herbicidePerennial
Spreading roots
Reproduces by seed, spreading roots, and plant fragments

Leafy spurgeBeginning to move resources to the rootsTreat plants with herbicidePerennial
Spreading roots
Reproduces by seed and spreading roots

Musk thistleOlder plants dropping seedRemove flowers, bag, put into trashBiennial
Taproot
Reproduces by seed
Next year plan on doing your removal in the spring and early summer before the flowerbuds form (when plants are less than 12 inches tall)
Musk thistleNew rosettesRemove or treat with herbicide

Myrtle spurgeDropping seedRemove or treat with herbicidePerennial
Deep taproot
Reproduces by seed, spreading roots, and plant fragments
Wear gloves and long sleeves if pulling.     The sap of this plant is corrosive.
Oxeye daisyDropping seedRemove, bag, put into trashPerennial
Rhizomes
Reproduces by seed and rhizomes

Oxeye daisyNew seedlingsTreat plants with herbicide

Poison hemlockNew seedlingsTreat seedlings with herbicideBiennial
Taproot
Reproduces by seed

Purple loosestrifeDropping seedTreat plants with herbicidePerennial
Deep spreading roots
Reproduces by seed, spreading roots, and plant fragments

Russian oliveAll stagesCut at base and treat surface with herbicide.
 Chip and scatter 
Perennial
Deep roots
Reproduces by seed

Scotch thistleOlder plants dropping seedRemove flowers, bag, put into trashBiennial
Taproot
Reproduces by seed
Next year plan on doing your removal in the spring and early summer before the flowerbuds form (when plants are less than 12 inches tall)
Scotch thistleNew rosettesRemove or treat with herbicide

TeaselDropping seedRemove, bag, put into trashBiennial
Taproot
Reproduces by seed
Next year plan on doing your removal in the spring and early summer before the flowerbuds form (when plants are less than 12 inches tall)
TeaselNew rosettesRemove or treat with herbicide

Yellow toadflaxAll stagesTreat with herbicidePerennial
Spreading roots
Reproduces by seed and roots
Do NOT pull.  Pulling breaks the root and creates new plants.
OthersVisit our weed profile pages