July

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

Purple Loosestrife

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    • A perennial that spreads by roots and seeds
    • Grows up to six to eight feet tall
    • Produces a spike of showy purple flowers in August
    • Stems have square edges
    • In the past, this weed was intentionally planted in gardens, but has now escaped and is very difficult to control
    • Grows in moist or marshy sites along streams or ditches, and in wetlands
    • Do NOT pull, dig, or cut the roots, as this may stimulate new growth
    • Chemical controls are needed

Russian Knapweed

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    • A perennial weed that spreads by root and seed
    • Grows two to three feet tall
    • Produces small pink, white, or lavender flowers during summer months
    • Upper part of root is dark brown to black in color
    • Grows in dense colonies along roadsides, riverbanks, and ditches, and in pastures and waste places
    • Cut or mow prior to seed set to reduce current year's growth; will not kill plants
    • Chemical controls are needed

Scotch Thistle

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    • A biennial weed that spreads by seed only
    • Grows up to 12 feet tall
    • Violet to reddish flowers are 1 to 2 inches in diameter
    • Stems have broad, spiny wings
    • Plant has a grayish appearance and is very spiny
    • Grows in along roadsides and in waste places and disturbed soils
    • Dig, removing the top two inches of root prior to seed set
    • Chemical controls are available

Spotted Knapweed

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    • A biennial to short-lived perennial weed that spreads by seed only
    • Grows one to three feet tall, sometimes taller
    • Produces small pink, white, or lavender flowers during summer months
    • Bracts below flower head have dark spots but are not spiny
    • Grows in disturbed soil, rangelands, pastures, meadows and roadsides
    • Cut or mow prior to seed set to reduce current year's growth, or dig, removing the top 2-6 inches of root
    • Chemical controls are available

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

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

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

Curlycup Gumweed

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    • Biennial or short-lived perennial
    • Grows 1 to 3 feet tall with fibrous root systems
    • Leaves are about one inch long, rounded at the tip, toothed on the edges and grow alternately on the stem
    • Yellow flowers are about one inch in diameter and sticky or gummy underneath
    • Commonly seen growing along roadsides
    • Difficult to remove by hand or weed wacker
    • Herbicides are available

Dalmatian Toadflx

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    • A perennial that spreads by roots and seeds
    • Grows up to 3 feet tall
    • Has yellow flowers that resemble snapdragons
    • Leaves are heart-shaped and clasp the stem
    • Grows along roadsides and in rangelands or pastures
    • In the past, this weed was intentionally planted in gardens, but has now escaped and is very difficult to control
    • Pull or dig for several years, removing as much root as possible.
    • Mowing is not effective and may spread the weed
    • Chemical controls are available

Mullein

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  • Biennial
  • Grows 2 to 6 feet tall
  • Grayish-green in appearance with fuzzy leaves and stem
  • Leaves grow alternately and are prominently veined
  • Yellow flowers appear on long terminal spikes that form at the top of the plant
  • Remove prior to seed set by pulling, hoeing or mowing,
  • Easiest to pull during the first year of growth
  • Herbicides are available.

Prickly Lettuce

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  • Winter annual or biennial that reproduces only by seed
  • Grows 1 to 5 feet tall
  • Single stem contains a milky sap
  • Lower leaves grow alternately on the stem, are lobed and prickly underneath, and can be 2 to 5 inches long
  • Small yellow flower heads grow on the terminal branches
  • Remove prior to seed set by pulling, hoeing or mowing
  • Herbicides are available

Puncturevine

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  • Annual
  • Forms flat, spreading mat with stems up to 5 feet long
  • Leaves are small and include 4 to 8 pairs of leaflets
  • Flowers are tiny, yellow, and have 5 petals
  • Produces many spiny fruits that break apart into tack-like "goatheads" that can puncture tires and feet
  • Plant continues to flower and produce seed until frost
  • Remove prior to seed set by pulling, hoeing or digging; easiest when plant is small
  • Herbicides are available.

Western Salsify

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  • A biennial
  • Grows 1 to 3 feet tall and has a long taproot
  • Leaves are long and very narrow
  • Flower heads grow at the top of the plant and look somewhat like a dandelion, producing wind-blown seeds
  • Contains a milky juice
  • Remove prior to seed set by pulling, hoeing or mowing
  • Herbicides 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

Diffuse Knapweed

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

Western Whorled Milkweed

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  • Perennial that reproduces by seed as well as deep horizontal-growing root systems
  • Reaches 1 to 3 feet tall
  • Grows a single, unbranched smooth stem
  • Very narrow leaves 2 to 5 inches in length grow in whorls up the stem
  • Greenish-white flowers grow in flat clusters at the top of the plant
  • Produces a milky sap
  • Leaves and other plant parts are poisonous
  • Herbicides are available

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.

Common Mallow

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.

Poison Hemlock

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  • Biennial
  • Grows 6 to 8 feet tall (or more)
  • Stems are large and have purple splotches
  • Leaves are finely divided and resemble parsley
  • Flowers are white and form umbrella-shaped clusters
  • Grows in moist areas along ditches and fencelines
  • All plant parts are very poisonous, including the root
  • Remove prior to seed set by pulling or digging. Be sure to wear gloves and dispose of plant material carefully.
  • Herbicides are available

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

Chicory

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  • A many-branched perennial
  • Grows up to 6 feet tall from a deep taproot
  • Lower leaves are deeply toothed
  • Upper leaves are sparse and small, giving the plant a stemmy look
  • Many sporadic flowers are white to bluish-purple and up to 1 inch in diameter
  • Contains a milky juice
  • Remove prior to seed set by pulling, hoeing or mowing
  • Herbicides may be needed

Other

Broadleaf and Buckhorn Plantain

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  • Perennials
  • Often found growing in lawns
  • Leaves vary in width between species (broadleaf has wider leaves, buckhorn narrower)
  • All have prominent parallel veins in leaves
  • A central flowering stem sends up long, flowering spike
  • Remove prior to seed set by pulling or hoeing
  • Herbicides may be needed

Curly Dock

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