Despite the late summer warmth, not much is left blooming around Laramie this time of year. One exception is the subalpine gumweed, Grindelia subalpina, which is still looking quite robust in the wilder parts of town.
The name subapline gumweed is yet another example of stupid common names, because it grows all the way down to the plains, so the subalpine part isn’t very accurate! Laramie, even at 7200 feet, doesn’t quite reach subalpine heights.
Curlycup gumweed, Grindelia squarrosa, is another similar-looking species of gumweed that grows in the area (and throughout the U.S.). Both species are native, favor dry areas, and bloom well into September. The main way to tell G. subalpina from G. squarrosa is by the leaves. The website Eastern Colorado Wildflowers states “Teeth on leaves of G. subalpina are spaced further apart, are pointed and point outwards from the margin. Teeth on G. squarrosa are close together, somewhat rounded and point toward the leaf tip.”
Coloradowildflowers.org adds, “Subalpine Gumweed’s base of the leaf tapers toward the point of attachment on the stalk, forming a petiole-like structure. Curlycup Gumweed leaves are stemless, oblong in shape & clasping the stem.”
Subalpine gumweed can also be called mountain gumweed, stickyhead or just plain gumweed. By those names, you can probably tell that some part of this plant is viscous (the bracts are sticky with resinous glands). G. subalpina can be found only in Wyoming, Colorado and New Mexico.