''Packera obovata'', commonly known as roundleaf ragwort, spoon-leaved ragwort, roundleaf groundsel, or squaw-weed, is an erect

perennial A perennial plant or simply perennial is a plant that lives more than two years. The term ('' per-'' + '' -ennial'', "through the years") is often used to differentiate a plant from shorter-lived annuals and biennials. The term is also wide ...

herb In general use, herbs are a widely distributed and widespread group of plants, excluding vegetables and other plants consumed for macronutrients, with savory or aromatic properties that are used for flavoring and garnishing food, for medicinal ...

in the

Asteraceae The family Asteraceae, alternatively Compositae, consists of over 32,000 known species of flowering plants in over 1,900 genera within the order Asterales. Commonly referred to as the aster, daisy, composite, or sunflower family, Compositae w ...

(aster) family native to eastern North America. It was previously called ''Senecio obovatus''. Basal and lower leaves are obovate with toothed margins, while upper leaves are pinnately divided. The ray flowers are yellow and the disk flowers orange-yellow, the inflorescences being held well above the foliage.

Description

''Packera obovata'' is an erect perennial herb growing to a height of up to . It has fibrous roots and a basal rosette of leaves up to across. The basal leaves are mid-green and hairless, circular, oval or

obovate The following is a list of terms which are used to describe leaf morphology in the description and taxonomy of plants. Leaves may be simple (a single leaf blade or lamina) or compound (with several leaflets). The edge of the leaf may be regular o ...

in shape and have crinkly toothed margins. The leaf stalks are about the same length as the leaf blades, green or purplish in colour and usually hairless; some have slight winging and may be cobwebby-pubescent. The flower stalk may also be cobwebby at the base, and bears two or three alternate pinnatifid leaves with irregular lobes. It is topped by a flat-headed

panicle A panicle is a much-branched inflorescence. (softcover ). Some authors distinguish it from a compound spike inflorescence, by requiring that the flowers (and fruit) be pedicellate (having a single stem per flower). The branches of a panicle are of ...

, each individual flower-head being up to in diameter. The flower-head has a single row of linear-lanceolate green bracts, eight to sixteen yellow ray-florets and a central mound of orange-yellow disk florets. Both ray and disk florets are followed by brown

achene An achene (; ), also sometimes called akene and occasionally achenium or achenocarp, is a type of simple dry fruit produced by many species of flowering plants. Achenes are monocarpellate (formed from one carpel) and indehiscent (they do not ope ...

s set in tufts of white hair. The achenes are dispersed by the wind, and the plant can also spread by vegetative growth from

stolon In biology, stolons (from Latin '' stolō'', genitive ''stolōnis'' – "branch"), also known as runners, are horizontal connections between organisms. They may be part of the organism, or of its skeleton; typically, animal stolons are external s ...

s or

rhizome In botany and dendrology, a rhizome (; , ) is a modified subterranean plant stem that sends out roots and shoots from its nodes. Rhizomes are also called creeping rootstalks or just rootstalks. Rhizomes develop from axillary buds and grow hori ...

Distribution and habitat

The native range of ''P. obovata'' is northern Mexico, the eastern United States and south-eastern Canada, extending from

Coahuila Coahuila (), formally Coahuila de Zaragoza (), officially the Free and Sovereign State of Coahuila de Zaragoza ( es, Estado Libre y Soberano de Coahuila de Zaragoza), is one of the 32 states of Mexico. Coahuila borders the Mexican states of N ...

Quebec Quebec ( ; )According to the Canadian government, ''Québec'' (with the acute accent) is the official name in Canadian French and ''Quebec'' (without the accent) is the province's official name in Canadian English is one of the thirtee ...

and

Ontario Ontario ( ; ) is one of the thirteen provinces and territories of Canada.Ontario is located in the geographic eastern half of Canada, but it has historically and politically been considered to be part of Central Canada. Located in Central Ca ...

. It is most common in the southern half of the range. Typical habitats include moist but well-drained calcareous soils, wooded slopes, and rocky areas in shaded or semi-shaded locations.

Ecology

Flowers of ''P. obovata'' bloom in the early spring and are visited by

cuckoo bee The term cuckoo bee is used for a variety of different bee lineages which have evolved the kleptoparasitism, kleptoparasitic behaviour of laying their eggs in the nests of other bees, reminiscent of the behavior of cuckoo birds. The name is perhap ...

s, halictid bees, andrenid bees,

hoverflies Hover flies, also called flower flies or syrphid flies, make up the insect family Syrphidae. As their common name suggests, they are often seen hovering or nectaring at flowers; the adults of many species feed mainly on nectar and pollen, whi ...

tachinid flies The Tachinidae are a large and variable family of true flies within the insect order Diptera, with more than 8,200 known species and many more to be discovered. Over 1,300 species have been described in North America alone. Insects in this family ...

and various species of

beetle Beetles are insects that form the order Coleoptera (), in the superorder Endopterygota. Their front pair of wings are hardened into wing-cases, elytra, distinguishing them from most other insects. The Coleoptera, with about 400,000 describ ...

. The larvae of the northern metalmark butterfly (''Calephelis borealis'') feed on the leaves of the plant, and the '' white-crossed seed bug'' (''Neacoryphus bicrucis'') feeds on the seeds. Like many species of ragwort, the plant is

toxic Toxicity is the degree to which a chemical substance or a particular mixture of substances can damage an organism. Toxicity can refer to the effect on a whole organism, such as an animal, bacterium, or plant, as well as the effect on a subst ...

to many herbivorous mammals, but sheep seem more tolerant of it than are most other grazing animals. ''P. obovata'' forms colonies by spreading through

rhizomes In botany and dendrology, a rhizome (; , ) is a modified subterranean plant stem that sends out roots and shoots from its nodes. Rhizomes are also called creeping rootstalks or just rootstalks. Rhizomes develop from axillary buds and grow hori ...

. Dense colonies can form in wet, sunny areas, while the colony will be sparser with shorter plants in drier, shadier spots.

References

External links

Plants Profile for ''Packera obovata'' (roundleaf ragwort)
{{Taxonbar, from=Q7122971 obovata Flora of Northeastern Mexico Flora of the Northeastern United States Flora of the South-Central United States Flora of the Southeastern United States Flora of Eastern Canada Flora of the Appalachian Mountains Flora of the Great Lakes region (North America) Plants described in 1803 Taxa named by Gotthilf Heinrich Ernst Muhlenberg