Hieracium caespitosum Dumort.

Yellow King-Devil

Hieracium_caespitosum_plant.jpg
STATS

Introduced
CC = *
CW = 5
MOC = 1

© SRTurner

Family - Asteraceae/Cichorieae

Habit - Perennial forb with rhizomes and usually stolons, colonial, with milky sap.

Hieracium_caespitosum_offsets.jpg Vegetative offsets.

© SRTurner

Stems - Erect, to 1 m, solitary to several, unbranched below the inflorescence, moderately to densely pubescent toward the base with light orangish brown, spreading to loosely ascending hairs 2-4 mm long having a bulbous or slightly expanded base, these becoming sparse or absent toward the tip, also inconspicuously pubescent with minute, branched hairs, especially toward the tip, also with moderate to dense, dark-colored, gland-tipped hairs toward the tip.

Hieracium_caespitosum_stem1.jpg Lower stem and node.

© SRTurner

Hieracium_caespitosum_stem2.jpg Upper stem just below inflorescence.

© SRTurner

Leaves - Basal and alternate, simple. Basal leaves persistent at flowering, sessile or with a short, indistinct, winged petiole, the blade 4-25 cm long, narrowly oblanceolate, sharply pointed at the tip, the surfaces and margins pubescent with moderate to dense, spreading, bulbous-based hairs (these often relatively dark-colored) and sparse to moderate, minute, branched hairs. Stem leaves only 1 or 2 toward the stem base, similar to but shorter than the basal leaves, mostly sessile, narrowly oblanceolate to linear, the base not clasping the stem.

Hieracium_caespitosum_basals.jpg Basal leaves.

© SRTurner

Hieracium_caespitosum_leaf1.jpg Lower stem leaf, adaxial.

© SRTurner

Hieracium_caespitosum_leaf1a.jpg Adaxial leaf hairs.

© SRTurner

Hieracium_caespitosum_leaf2.jpg Lower stem leaf, abaxial.

© SRTurner

Hieracium_caespitosum_leaf2a.jpg Abaxial leaf surface, showing both long simple hairs and minute stellate hairs.

© SRTurner

Inflorescences - Short, spreading panicles, sometimes reduced to a loose or dense terminal cluster of few to several heads.

Hieracium_caespitosum_inflorescence1.jpg Inflorescence.

© SRTurner

Heads - Ligulate. Involucre 6-9 mm long, the inner series of bracts narrowly oblong-elliptic, pubescent with spreading, dark-colored, gland-tipped hairs and usually also inconspicuous, minute, cobwebby, branched hairs, the outer series variable and grading into the inner series, some of the bracts more than 1/2 as long as those of the inner series. Florets 25-70 per head.

Hieracium_caespitosum_involucres1.jpg Flowering heads.

© SRTurner

Hieracium_caespitosum_involucres2.jpg Involucres.

© SRTurner

Florets - Corollas 8-14 mm long, bright yellow. Pappus bristles 4-6 mm long, white.

Hieracium_caespitosum_ligules.jpg Ligulate florets.

© SRTurner

Hieracium_caespitosum_florets.jpg Florets, with white pappus bristles.

© SRTurner

Fruits - Achenes 1.5-2.0 mm long, more or less cylindrical, not tapered at the tip.

Flowering - June - September.

Habitat - Open grassy areas.

Origin - Native to Europe.

Lookalikes - Other species of Hieracium. More broadly, numerous other species within the Cichorieae tribe (e.g. species of Crepis, Hypochaeris, Leontodon, and others).

Other info. - This plant is rare in Missouri, thus far reported (in 1993) from only a single location at or near Shaw Nature Reserve in

Franklin County. The Missouri occurrence is far disjunct from other populations, and its history is unknown. The plant is more common in the northeastern U.S., and also in the Northwest, where it is considered a noxious weed. It is distinguished from other species of Hieracium by its white pappus bristles (other Missouri species have tan to brown pappus). Another differentiating factor is its colonial habit, resulting from its production of stolons and rhizomes. The dark colored hairs on the involucre and upper stem, and the relatively few and basally disposed stem leaves, are also characteristic. The plant is tolerant of drought and poor, compacted soils.

Species in the Hieracium genus are often named hawkweeds. Some were once used in traditional medicines to improve eyesight, and the ancient Greek Pliny reported that hawks ate it in order to gain sharper vision.

Another name for the species is Pilosella caespitosa.

Photographs taken at Shaw Nature Reserve, Franklin County, MO, 5-31-2021 (SRTurner).