Grindelia squarrosa (Gumweed)
|Also known as:||Curlycup Gumweed, Curly-top Gumweed|
|Life cycle:||biennial, short-lived perennial|
|Habitat:||sun; disturbed soil; fields, prairies, along roads and railroads|
|Bloom season:||July - October|
|Plant height:||6 to 36 inches|
|Wetland Indicator Status:||GP: UPL MW: FACU NCNE: FACU|
|MN county distribution (click map to enlarge):|
|National distribution (click map to enlarge):|
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3 to 20 flower heads per plant, each 1-inch across with 25 to 40 yellow petals (ray flowers) around a yellow center disk, the disk about as broad as the rays are long. The narrow bracts surrounding the base of the flower are in 5 or 6 layers; bracts are spreading, strongly curved, and exude a sticky resin.
Leaves and stems:
Leaves are 1 to 2½ inches long, somewhat variable in shape but generally oblong with a pointed tip, stalkless, more or less clasping, and typically twisted in relation to the sun's position. Edges are toothed, the teeth pointed or more often rounded. Surfaces are hairless and gland-dotted. Uppermost leaves are smaller, more linear and may be toothless or nearly so. Stems are erect to ascending, often heavily branched in the upper plant, hairless, straw-colored to tinged red.
Fruit is a dry, brown seed without hairs but with 2 to 8 awns at the tip.
Gumweed is easily identified by its unusual bracts. It is typically found along roadsides, railroads, and other disturbed soils. At one time it was considered a county-level noxious weed but Round-up Ready crops took care of that.
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Photos by K. Chayka taken in Lake and Ramsey counties. Other photos courtesy Peter M. Dziuk.
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