Gumweed (4)
The Grindelia genus, Gumweeds, ooze a whitish, viscous, resinous fluid from their flower buds so are very recognizable. There are conflicting descriptions of the species, but I think these are unique enough to be identified individually.
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Curlytop Gumweed Family:
Sunflower (Asteraceae) Grows to 16" with a wiry, reddish stem. Leaves are oblong and toothed with no stalks. Bracts are sticky and curl backwards. Flower heads have only disk flowers. Recognized by the USDA Plants Database but considered a variety of G. squarrosa by Flora of North America |
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Colorado Gumweed Family:
Sunflower (Asteraceae) Grows to 30" with stout stems and fleshy leaves. Flower heads do not have ray flowers, are 1" across and very sticky. Bracts are bright green and curved backwards. Grows south from Denver on the eastern slope. Identified from G. K. Guennel's Wildflowers of Colorado. Flora of North America recognizes it as a variety of Grindelia hirsutula, the USDA Plants Database lists it as a distinct species. |
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Curlycup Gumweed Family:
Sunflower (Asteraceae) Grows to 2 feet with a green or whitish stem. Leaves are oblong and toothed with no stalks. Bracts are in 5 to 6 rows and are strongly hooked. Ray flowers may or may not be present. Flora of North America reference. |
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Pointed Gumweed Family:
Sunflower (Asteraceae) Grows over 3 feet tall with a whitish brownish stem. Leaves have no stalks and lance-shaped and may or may not be toothed. Bracts are thick and are strongly hooked. Flower head has no ray flowers. Flora of North America recognizes it as a variety of Grindelia hirsutula, the USDA Plants Database lists it as a distinct species. |
