Eurybia hemispherica
Eurybia furcata
single-stem bog or southern prairie aster, southern prairie aster
fork aster
1–4, erect or ascending, often reddish, simple, straight to stict, proximally glabrous, distally ± sparsely strigillose (at least arrays).
1–5+, erect, simple, ± flexuous distally (± ridged from decurrent leaf bases), glabrate proximally, sparsely villous distally.
basal and cauline, blades with adaxial midvnerves raised (grooved abaxially), sometimes with 1–2 ± parallel pairs of more obscure secondary nerves (veins obscure), lance-ovate or linear-lanceolate to linear, coriaceous, margins usually entire, sometimes remotely spinulose-toothed, often revolute apically, indurate, scabrous, apices acute, acuminate or obtuse, indurate, abaxial faces glabrous or glabrate, adaxial sparsely scabridulous (hairs minuscule, basal “bulb” bearing terminal seta);
basal withering by flowering, petioles marcescent, ± winged;
proximal petiole bases sheathing, blades 50–175 × 3–12 mm, bases attenuate or cuneate;
cauline progressively sessile and reduced distally, 25–125(–150) × 1.5–8 mm, bases clasping to subclasping.
basal and cauline (grayish green abaxially), bases often oblique, margins serrate, veins prominent, abaxial faces scabrous, adaxial hirsute;
basal and proximal cauline withering by flowering (rosettes produced in late season, absent in spring), short-petiolate, petioles winged, sheathing, blades ovate-lanceolate, 40–130 × 20–90 mm, bases rounded to subcordate, apices obtuse to acute;
mid short-petiolate, narrowly winged, wings revolute, bases dilated, sheathing, ciliate, blades ovate to lance-ovate, 100–120(–150) × (30–)60–80 mm, gradually reduced distally, bases shallowly cordate or truncate to rounded, margins sharply serrate, teeth mucronate, apices acuminate;
distal (arrays) subpetiolate or sessile, ovate, 8–70 × 4–23 mm, bases sheathing or clasping.
2–80 mm or subsessile;
bracts 0–4, linear-lanceolate, 10–35 × 0.5–2 mm, mucronulate, grading into phyllaries.
0.5–3(–5) cm, villous;
bracts 0–3.
hemispheric, 8–12(–15) mm, shorter than pappi.
campanulate, 6–8(–10) mm, much shorter than pappi.
15–30;
corollas usually violet-purple, seldom white, (10–)13–15(–20) × 1.3–3 mm.
(12–)15–20;
corollas white, sometimes becoming pink or lavender, 12–18 × 1–2.5 mm.
(40–)52–80+;
corollas light yellow turning brown, 5.8–6.6 mm, ± ampliate, tubes (1.7–2.2 mm) shorter than narrowly campanulate throats (3.4–4 mm), lobes erect, lanceolate and cuspidate or acuminate, 0.7–1.2 mm.
25–35+;
corollas cream or light yellow becoming purple, 6–7(–8) mm, slightly ampliate, tubes cylindric, lengths about twice funnelform throats, lobes erect, lanceolate, 0.8–1.2 mm (glabrous).
48–64 in 4–6 series, oblong-lanceolate or lanceolate (outer) to oblong or lanceolate-linear (inner), unequal, coriaceous (outer) to membranous (inner), bases indurate, rounded (outer), green zones slightly expanded, in 1/2–4/5 distal portions (outer), margins indurate, scabrous or scabroso-ciliate, edges and apices purplish in inner, apices ascending or squarrose to strongly reflexed, acute to acuminate, mucronulate, faces glabrous.
ca. 40 in 5 series, oblong (outer) to linear-lanceolate (inner), strongly unequal, membranous, bases indurate and low-keeled or rounded abaxially, green zones in distal 1/4–1/3, obovate, poorly defined, margins hyaline, scarious, villoso-ciliate, inner often purplish, apices appressed, obtuse to rounded, faces villous, eglandular.
1–35+ in elongate, usually racemiform to spiciform, sometimes ± flat-topped, corymbiform arrays, branches robust, ascending.
4–32+ in flat-topped, corymbiform arrays.
brown, cylindro-obovoid to fusiform, slightly flattened, 2.6–3.7 mm, ribs 9–16 (stramineous to olive, crowded), faces ± densely strigillose;
pappi of tawny to cinnamom (coarse, rigid, sometimes apically clavellate) bristles 6–7.5 mm, equaling disc corollas.
brown, fusiform, (2.5–)3–3.5(–4) mm, ribs 8–10(–12), crowded, stramineous to tan, faces ± strigillose;
pappi of tawny (apically sometimes clavellate) bristles 6–7 mm, equaling or slightly shorter than disc corollas.
= 18, 36.
= 18.
Eurybia hemispherica
Eurybia furcata
Eurybia hemispherica is of conservation concern in Florida, Georgia, and Kentucky. A. Cronquist (1980) stated that this species and E. paludosa are difficult to separate but geographically distinct (see under 21. E. paludosa). The two species are often treated as infraspecific taxa of E. paludosa. Eurybia hemispherica is diploid and tetraploid, while E. paludosa has been reported only as a tetraploid. There is great morphologic variation in E. hemispherica, from slender individuals, reminiscent of E. paludosa, to very robust, distinctive plants. Arrays in E. hemispherica are usually racemiform; well-developed ones may be distally corymbiform and resemble the arrays of E. paludosa, although the proximal part remains somewhat racemiform (i.e., proximal heads borne on short, simple branches, or tufts of leaves are present). Phyllaries in E. hemispherica may be superficially similar to those of E. paludosa, but often the outer phyllaries are similar to peduncular bracts (and in fact may have been recruited from such), being more triangular, coriaceous, and parallel-veined, a feature never encoutered in E. paludosa; such phyllaries strongly resemble those of E. eryngiifolia. Other characters may help distinguish the two species. Eurybia paludosa usually has thin peduncles, hirtello-puberulent to villoso-hirsute peduncles and phyllaries, and ciliate phyllary margins along the indurate bases. In E. hemispherica, the pedicels are thin to usually robust, when present, the phyllaries are glabrous to sparsely strigillose, and the phyllary margins along the indurate bases are scabrous or scabroso-ciliate, not long-ciliate.
(Discussion copyrighted by Flora of North America; reprinted with permission.)
D. H. Les et al. (1991b) studied the population genetics of this restricted taxon, and Les et al. (1992) its distribution and autecology in Wisconsin. J. A. Reinartz and D. H. Les (1994) showed that the species is developing self-compatibility in response to small populations.
Eurybia furcata is uncommon throughout its range and is considered endangered or threatened in all states where it occurs; it is known only from historic records in Arkansas. It is in the Center for Plant Conservation’s National Collection of Endangered Plants.
(Discussion copyrighted by Flora of North America; reprinted with permission.)
KS Wildflowers
LA Plants
MO Plants
WildflowerSearch
iNaturalist
USDA Plants Database
IL Wildflowers
MI Flora
