[Members of the
Sunflower Family with Flower Heads like Sunflowers or Daisies in the Columbia River Gorge of Oregon and Washington]
Idaho Gumweed, Low Gumweed
Grindelia nana var. nana
Synonyms: Grindelia hirsutula, Grindelia nana var. integerrima, Grindelia nana var. integrifolia, Grindelia nana ssp. nana, Grindelia squarrosa var. integrifolia
The photo at left shows the upper stem and flower heads of low gumweed as seen on dry shores of the Deschutes River about one-quarter mile upstream from its junction with the Columbia River.........September 1, 2007. Note the numerous pointed bracts that are reflexed downwards at the tips.The photo at right shows a close-up view of a flower head of low gumweed as seen on dry shores of the Deschutes River about three miles upstream from its junction with the Columbia River.........November 20, 2020.
The photo at right shows a view down onto the flowerhead of low gumweed (var. nana) from Steptoe Butte, Palouse country in eastern Washington.........6/27/98.
Low gumweed is a smooth-surfaced perennial, having a taproot
and many branched stems. It ranges in height from 10 to 80 cm. The leaves are
largest near the base of the stems, and reduced in size towards the tips. Each
leaf is spiny margined to entire, with the lower leaves oblanceolate and occasionally
clasping at the stem, and the smaller upper leaves more often with clasping
bases. Both the leaves and stems are glabrous.
The flower heads have both ray and disk flowers. The involucre
(or bracts below the flowers) are conspicuously spiny-tipped, with the spines
arcing outwards. The bracts are also distinctly non-resinous.
The flower heads of variety nana have a disk about 8
to 15 mm across, and an involucre about 1 cm tall. Variety integrifolia
has disks to 25 mm across, and an involucre 10 to 17 mm high. The species has
roughly 12 to 25 ray flowers.
Low gumweed is found in dry open places in the lowlands and
into the foothills.
Variety Grindelia nana var. nana is found primarily in
eastern Washington and northern Idaho, and southward to Union County, OR.
Variety Grindelia nana var. integrifolia is found in
the range of the species, from eastern Washington and eastern Washington, extending
east to western Montana, and also found in northwestern California and southwestern
Oregon. It may occur at other western locations as an introduced weedy species.
In the Columbia River Gorge, low gumweed is found east of the
mouth of the Deschutes River at elevations below 200'.
The photo at left shows the leafy, branched stem of low gumweed as seen on dry shores of the Deschutes River about one-quarter mile upstream from its junction with the Columbia River........September 1, 2007. Low gumweed as seen at right on the dry (winter-flooded) shores of the Deschutes River about one-half mile upstream from the Columbia River.........July 27, 2011.
Low gumweed as seen at right on the dry (winter-flooded) shores of the Deschutes River about one-half mile upstream from the Columbia River...............July 27, 2011.