Hymenoxys herbacea (E.L. Greene) Cronq. LakesideLakeside daisy, daisy Page 1 State Distribution Best Survey Period Photos by Michael Oldham, NHIC Archives Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Status: Federal threatened, State endangered Hymenoxys herbacea differs from H. acaulis primarily in its bright green leaves that lack pubescence, in Global and state rank: G2/S1 contrast to the dull green and densely soft-hairy leaves of the latter. Other common names: Eastern four-nerved daisy, This species likely originated from ancestors that stemless four-nerved daisy colonized the Great Lakes region in the Xerothermic interval, a post-glacial warming period during which Family: Asteraceae (composite family) many drought-tolerant prairie and western cordillera (mountain range) plants migrated eastward (Cusick Synonyms: Hymenoxys acaulis (Pursh) Parker var. 1991). As climate subsequently changed again, becom- glabra (A. Gray) Parker, Tetraneuris herbacea E.L. ing cooler, increasingly moist, and humid, H. herbacea Green, Actinea herbacea (E.L. Greene) Robinson, persisted in favorable dry habitats (U.S. Fish and Actinea scaposa (Pursh) Spreng. var. glabra (A. Wildlife Service 1990). Gray) Cronquist, Actinella scaposa Nutt. var. glabra A. Gray (Cusick 1991). Total range: Lakeside daisy is an endemic restricted to the Great Lakes area, within which it is one of the Taxonomy: Hymenoxys herbacea was formerly region’s rarest plants. In the United States it is known considered a glabrous Midwestern variety of the wide- only from the Marblehead Peninsula area in northern ranging Hymenoxys acaulis of the western Great Ohio, three restored populations in northern Illinois Plains. Great Lakes populations are separated from this (where it was known historically from two sites), and a very similar species by 900-1400 km (559-870 mi) single, extremely small colony in Michigan’s Upper (Cusick 1991). Based on significant genetic and mor- Peninsula. In Ontario, Canada, where Lakeside daisy is phological data, and in view of the strong physical most abundant, it occurs along much of the southern isolation from western Hymenoxys populations, Cusick coast of Manitoulin Island and in several restricted areas (1991) classified the closely related plants of the Great near the tip of the Bruce Peninsula. Lakes as a distinct species. Our plants are now consid- ered H. herbacea, which Cusick established as the State distribution: This Great Lakes endemic is nomenclaturally correct name. Morphologically, known from a single location in the eastern Upper Peninsula, where a small, extremely localized colony of Michigan Natural Features Inventory P.O. Box 30444 - Lansing, MI 48909-7944 Phone: 517-373-1552 Lakeside daisy, Page 2 approximately 200 clumps occurs along a roadside in Alvars are globally rare natural communities (see Mackinac County. The occurrence of this species was limestone pavement lakeshore abstract), forming unique unknown to Michigan botanists until 1996, when mem- plant assemblages in which prairie grasses, sometimes bers of the Ontario Federation of Naturalists (OFN) mixed with boreal species, form thin turfs over porous divulged this location to members of the State Technical limestone and dolomite, functioning much like karst Committee on plants. (sinkhole) systems. Spring flooding in many sites is followed by summer drought, which impedes woody Recognition: Lakeside daisy is a clump-forming, plant establishment and succession. Fire may also play a herbaceous perennial that produces solitary, daisy- role in these systems. In Ontario, Lakeside daisy like flowers on stout, hairy stalks. The leaves form associates include such characteristic species as dense basal rosettes that arise from a short, thick, Sporobolus heterolepis (prairie dropseed), branching base (caudex) with a similarly short, thick Muhlenbergia richardsonis (mat muhly), Carex taproot. The narrow, one-nerved, dark green richardsonii (Richardson’s sedge), C. scirpoidea leaves, which may range to about 16 cm in length, are (bulrush sedge), Solidago houghtonii (Houghton’s lanceolate (lance-shaped) to oblanceolate (narrower at goldenrod), Juniperus virginiana (Eastern red cedar), the base), and in addition to being somewhat thick in J. communis (ground juniper), Saxifraga virginiensis texture, are strongly punctate (dotted with glands). (early saxifrage), Geum triflorum (prairie smoke), Flowers are borne solitarily on relatively stout, Bouteloua curtipendula (side-oats grama grass), and softly hairy peduncles that elongate through the Cirsium hillii (Hill’s thistle). flowering period, ranging from about 10-40 cm in height In Michigan, Lakeside daisy does not occur in an when seeds are dispersed. The bright yellow, daisy- alvar community, but its setting, albeit on a roadside, is like flower heads, as in similar composites, are inflo- unique and similar in many ways to alvar habitat. The rescences composed of both disk (central) and ray colony occurs on a thin mat of vegetation underlain by a (outer) florets, the ray florets 3-toothed on the margin. thick tufa deposit, a rock formation created via the The fruits are small, top-shaped, hairy achenes. precipitation of calcium from alkaline groundwater seeps It is unlikely that flowering plants of Lakeside daisy and springs. In terms of landscape setting, the micro- would be confused with another species, particularly habitat lies in the upland transition zone of an extensive because there are very few early blooming composites northern fen complex to the south. Characteristic and none that would even be superficially similar to this associated plants include Thuja occidentalis (northern rarity. white cedar), Juniperus horizontalis (creeping juniper), Selaginella selaginoides (spikemoss), Tofieldia Best survey time/phenology: Hymenoxys herbacea glutinosa (false asphodel), Carex flava (sedge), Carex is an early blooming composite with a relatively narrow crawei (sedge), Zigadenus glaucus (white camas), flowering period. Michigan’s sole colony has flowered Parnassia glauca (grass-of-Parnassus), Eleocharis from the latter part of May to early June, the best period rostellata (spike-rush), and Senecio paupercula likely being the last week of May through the first week (ragwort). Among the several rare associates are of June. This species is best sought during the blooming Houghton’s goldenrod, bulrush sedge, Richardson’s period, owing to its striking yellow flowers and clump- sedge, Pinguicula vulgaris (butterwort), and Erigeron forming growth habit. Lakeside daisy can be recognized hyssopifolius (hyssop-leaved fleabane). Interestingly, in sterile condition by experienced botanists, who may several notable alvar species are included among the be able to conduct inventories based on knowledge of aforementioned Michigan associates. this species’ growth habitat and specific habitat require- ments. Plants may occasionally bloom in late summer, Biology: Lakeside daisy is a perennial herb. Clumps although it is not common. of genetic individuals can expand by producing additional rosettes at the tip of the caudex. As plants age over the Habitat: In the main portion of its range, such as years, the older rosettes in the middle senesce and die Manitoulin Island in northern Lake Huron, lakeside daisy back as new ones are added on the periphery, resulting occurs primarily in the limestone pavement community in a “donut’-shaped form. Lakeside daisy is a self- known widely as alvar, although it also inhabitats lime- incompatible species, with pollination achieved by stone or dolomite cliffs near the Lake Huron shore. bumble bees and small carpenter or halictid bees, Michigan Natural Features Inventory P.O. Box 30444 - Lansing, MI 48909-7944 Phone: 517-373-1552 Lakeside daisy, Page 3 although wind pollination may also occur. An extensive widely disparate populations in the Great Lakes region. overview of Lakeside daisy reproductive biology is Research regarding management techniques is also provided in the Federal Recovery Plan (U.S. Fish and desirable to determine how to best maintain and per- Wildlife Service 1990) and by DeMauro (1993). petuate this rare Great Lakes endemic. Conservation/management: As a Federally listed Related Abstracts: Limestone pavement lakeshore, species, the conservation of Lakeside daisy in the prairie Indian-plantain, English sundew, prairie smoke, United States is guided by an approved Recovery Plan. dwarf lake iris, mat muhly, Houghton’s goldenrod, prairie The plan provides goals and objectives for recovery dropseed, Hine’s emerald dragonfly, incurvate emerald actions, as well as criteria with which to measure dragonfly. progress toward recovery. Although the Michigan locality was discovered several years after the approval Selected references: of the Federal Plan, useful information is provided within it, and any subsequent plan revisions should also incor- Cusick, A.W. 1991. Hymenoxys herbacea porate information and recovery actions for the Michi- (Asteraceae): An endemic species of the Great gan occurrence. At the present time, the primary need Lakes region. Rhodora, Vol. 93, No. 875, pp. 238- is protection for the highly fragile, remnant Michigan 241. colony. The population occurs on private land, although Cusick, A.W and J.F. Burns. 1984. Hymenoxys it is still uncertain if the colony falls partially within the acaulis (Pursh) Parker var. glabra (Gray) Parker, road right-of-way (ROW). The county road commis- p. A-537. In: R.M. McCance, Jr. and J.F. Burns, sion has been alerted concerning this location,