June

Purple to Pink Flowers

Canada Thistle

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  • A perennial that spreads by roots and seeds
  • Grows 1 to 4 feet tall
  • Has clusters of small, white to purple flowers at the end of the stems
  • Leaves are very spiny – it hurts to touch this weed!
  • Grows in moist and disturbed sites
  • This invasive weed is very aggressive and difficult to control
  • Pulling and burning do not control this weed, as they favor root resprouting
  • Chemical controls are needed

Musk Thistle

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  • A biennial thistle that sprouts from seed only
  • Grows to seven feet tall
  • Produces a single, large purple flower at the end of a bent, naked stem
  • Leaves have spiny margins
  • Stems are spiny and winged
  • Grows in varied locations, from vacant fields to roadsides to forest and rangelands
  • Dig, removing the top two inches of root prior to seed set
  • Chemical controls are available

Showy Milkweed

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  • Perennial that reproduces by seeds or root stalks
  • Grows 2 to 5 feet tall
  • Leaves large, thick and heavily veined
  • Stems are hairy
  • Leaves and stems contain a white, milky sap
  • Flowers grow in a 5-pointed star pattern in large clusters at the end of the stem
  • Remove prior to seed set by pulling, hoeing or mowing
  • Herbicides may be needed for control

Teasel

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  • A biennial that grows up to 6 feet tall
  • Leaves are large, toothed and prickly
  • Long prickly stems terminate in very spiny, prominent flower heads with tiny flowers
  • Grows in moist areas
  • Remove prior to seed set by pulling or hoeing; can grow back from remaining root fragments
  • Herbicides may be needed for control

Wild Iris

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  • A perennial that grows from a thick root mass
  • Leaves are long, narrow and striated
  • Produces the familiar purple iris flowers
  • Toxic to cattle
  • Grows in moist areas and pastures
  • Pulling or hoeing may be beneficial, but plant will reproduce from any remaining root
  • Herbicides are available

Tamarisk

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  • A perennial weed that spreads by root and seed
  • Grows as a shrub or deciduous tree; may be 5 to 20 feet tall
  • Produces delicate pink to white flowers during spring or summer
  • Leaves are tiny and resemble cedar leaves
  • Grows in dense colonies along riverbanks, and ditches; a mature tree may use as much as 200 gallons per day
  • Weeds will resprout vigorously if cut or burned
  • Chemical controls are needed

Yellow Flowers

Flixweed

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  • Winter annual that blooms early in spring.
  • Grows 8-24 inches tall.
  • Plants are bushy.
  • Leaves are feathery and deeply lobed.
  • Small, four-petaled yellow flowers.
  • Common in disturbed sites.
  • Remove prior to seed set by pulling or hoeing.

Yellow Starthistle

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  • An annual to short-lived weed that spreads by seed only
  • Grows one to three feet tall
  • Bright yellow flower heads are about 1 inch in diameter
  • Inch-long spines form at ends of bracts under flowerheads
  • Stems are winged, but not spiny
  • Grows along roadsides and in waste areas and grasslands
  • Pull, dig or mow at first sign of yellow flowers
  • Chemical controls are available

Sweetclover

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  • Annual or biennial
  • Grows up to 6 feet tall and as wide
  • Small three-lobed leaves
  • Sometimes confused with alfalfa
  • Flower spikes are 2 to 6 inches long, with many small flowers
  • Both yellow and white sweetclover are found locally
  • Used in seed mixes for erosion control
  • Remove prior to seed set by pulling, hoeing or mowing

Tumble Mustard

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  • Annual
  • Bushy and rounded appearance
  • Grows 2 to 5 feet tall
  • Lower leaves are larger and broadly lobed, while upper leaves are fine and segmented
  • Flowers are small and pale yellow, bunching at the top of the stem
  • After maturity, the dead plant can break free and tumble in the wind
  • Remove prior to seed set by pulling, hoeing or mowing

White Flowers

Perennial Pepperweed

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    • A perennial that spreads by roots and seeds
    • Grows to six feet tall
    • Produced white flowers resembling baby’s breath in June
    • Leaves are lance-shaped
    • Grows along streamsides, meadows, pastures, floodplains, and roadsides and forms dense colonies.
    • Do NOT pull, dig, or cut the roots as this may stimulate new growth
    • Chemical controls are needed.

Field Bindweed

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  • A perennial vine groundcover
  • Grows from an extensive root system
  • Leaves are about 1 inch long and arrowhead-shaped
  • Flowers are trumpet-shaped and resemble ornamental morningglory, but are smaller
  • Pulling, hoeing or mowing are likely to be ineffective due to the large root system, which extends up to 20 feet underground
  • Herbicides are available

Prickly Poppy

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  • A bluish-green spiny annual
  • Leaves are deeply lobed and spiny on the edges
  • Flowers are white, large and ruffled-looking, and have a yellow center
  • Plant contains yellow sap
  • Remove prior to seed set by pulling, hoeing and mowing.

Yarrow

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  • A perennial
  • Grows 1 to 2 feet tall
  • Stems are fuzzy
  • Leaves are grayish-green and featherlike
  • Tiny flowers grow in dense flat masses at tops of stems
  • Remove prior to seed set by pulling or hoeing
  • Forms a dense mat if mowed
  • Herbicides may be needed for control

Blue Flowers

Bachelor Buttons

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  • Annual with erect, branching stems and narrow leaves
  • Grayish-green in appearance
  • Grows up to 3 feet tall
  • Flowers are complex and multi-colored, ranging from white to purple
  • Related to knapweeds, but grown ornamentally
  • Remove prior to seed set by pulling or hoeing

Grasses

Medusahead

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    • An annual grass that sprouts from seed only
    • Grows to 2 feet tall
    • Produces a spike flower with long, twisted awns
    • Grows in many of the same locations as cheatgrass
    • Concentrates silica in the foliage, making it unpalatable to wildlife and livestock
    • Burns readily and increases fire danger.
    • Control by preventing seed set. Mow or pull when plants begin to flower.
    • Chemical controls are available

Foxtails

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  • A variety of common species are included in this category
  • Some are perennial, some are annual
  • All are between 1 and 2 feet tall
  • Some are bunchgrasses, some are not
  • They are green and bushy early in the season but become dry and brittle in mid- to late-summer
  • On some species, individual seeds break off and carry easily, sticking in socks and posing a danger to pets
  • Remove prior to seed set by pulling or hoeing
  • Mowing may result in prostrate growth with renewed flowering
  • Herbicides are available