[Thelypodys: The Genus Thelypodium East
of the Cascade Mountains of Oregon and Washington]
Fineleaf Thelypody, Manyflower Thelypody, Many-flowered Thelypody, Multiflora Thelypody, Thick-leaved Thelypodium
Thelypodium milleflorum
Synonym: Thelypodium laciniatum
var. milleflorum
The photo above shows the spidery flowers of fine-leaf thelypody
as seen on the northern edge of the Alvord Basin near Mickey Basin in southeastern
Oregon. Photographed May 29, 2000.
The
photo at right shows a coarsely toothed leaf of the lower stem of fine-leaf thelypody as seen on the northern edge of the Alvord Basin near Mickey
Basin in southeastern Oregon. Photographed May 29, 2000.
Characteristics:
Fine-leaf thelypody is a fairly robust biennial wildflower with
one to several erect stems from 45-130 cm high. The stems are typically much-branched
above, and are hollow or inflated in cross-section. The basal and lower stem
leaves are petioled and more or less narrowly oblong to lanceolate or ovate
in shape with pinnately lobed or occasionally coarsely toothed margins. The
upper stem leaves are much reduced in size. The herbage of the leaves and stems
is glabrous and glaucous.
The inflorescence is a dense, elongated raceme. The sepals are
white and measure 3.5-7 mm long. The petals are white with oblanceolate to spatulate
blades. The stout pedicel is 2.5-5 mm long and spreading in flower and sharply
upcurved in fruit. The fruits are siliques that are erect to erect-ascending,
3.5-8.5 cm long and flattened in cross-section. Each capsule is typically narrowed
between seeds (See photo below.).
Fine-leaf thelypody is very similar to thick-leaved
thelypody (T. laciniatum) but the latter has thinner leaves, a thinner,
non-hollow stem, and leaves which are more divided.
Habitat:
Fine-leaf thelypody may be found in arid, sandy soils below
1400 meters of elevation.
Range:
Fine-leaf thelypody is found along the Columbia River in central
Washington south through central and southeastern Oregon to Nevada and California
and east to Idaho and Utah.
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Fine-leaf thelypody
as seen on ashy soils along the west bank of the John Day River opposite the mouth of Esau Canyon, Cottonwood Canyon State Park. Photographed April 6, 2015.
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Close-up images of the whole plant, blooming inflorescence, and erect to ascending seed pods of fine-leaf thelypody as seen along Oregon Highway 206 at the John Day River.........April 19, 2007.
A habitat view of fine-leaf thelypody as seen next to the Oregon Highway 206 bridge on the west bank of the John Day River.........May 3, 2017.
Basal leaves of fine-leaf thelypody as observed in ashy soils along the Pinnacles Trail opposite the mouth of Esau Canyon, Cottonwood Canyon State Park and adjacent BLM lands, Sherman County, OR......January 20, 2018.
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What may be fine-leaf thelypody as seen along the Steelhead Falls Trail downstream from the falls, Stellhead Falls Wilderness Study Area.......April 25, 2018. If this isn't T. milleflorum, it will be T. laciniatum.
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Fine-leaf thelypody as seen on the
northern edge of the Alvord Basin near Mickey Basin in southeastern Oregon.
Photographed May 29, 2000. The stems are thick and hollow.
Note the sharply upturned pedicels
and the narrowing of the capsule between seeds.
Paul Slichter
