swamp milkweed

Names and Synonyms

Common Names

• swamp milkweed
• Pleurisy Root

Scientific Names

Accepted name

Synonyms

• Acerates incarnata

Regional and Traditional Names

Sources: Wikidata, Catalogue of Life

Taxonomical Classification

This plant, Asclepia incarnata, belongs to the kingdom Plantae and the phylum Streptophyta. Within the class Equisetopsida and subclass Magnoliidae, it is classified under the order Gentianaales and the family Apocynaceae. Finally, it is situated within the genus Asclepias.

Sources: The World Checklist of Vascular Plants (WCVP)

Distribution

This plant exhibits a broad geographical distribution across several different regions of the world. In Europe, its presence can be found within the territory of South European Russia. Moving across the Atlantic, it is widely distributed throughout Eastern Canada, specifically in Ontario, New Brunswick, and Nova Scotia. The species also extends its range into Western Canada, where it is located in Manitoba. These varied locations demonstrate the plant's ability to thrive in diverse environments across both continents.

Sources: The World Checklist of Vascular Plants (WCVP)

Botanical Identification

Life history

The life history of Asclepia incarnata is characterized by its classification as a perennial, meaning it lives for more than two years and typically undergoes a recurring seasonal cycle. As a perennial herb, the plant establishes a robust root system that allows it to survive dormant periods, often emerging from the soil each spring to undergo its reproductive stages. Its lifecycle begins with germination from seeds, which are often dispersed by wind via silky, tufted hairs, or through vegetative spreading. During the growing season, the plant focuses on biomass accumulation and the development of its distinct flowering structures. Once mature, it produces clusters of pink to purplish flowers that serve as a critical nectar source for pollinators, facilitating the sexual reproduction necessary to produce the next generation of seeds. Following the reproductive phase, the plant enters a period of senescence or dormancy as temperatures drop, retreating to its perennial rootstock to await favorable environmental conditions for the subsequent growing season.

Lifecycle :

perennial

Morphology

The morphology of Asclepia incarnata is characterized by its growth form as a non-woody herb, specifically classified as a forb. This terrestrial species grows as a self-supporting plant, rather than acting as a liana or vine, and does not require climbing structures to maintain its stature. It typically reaches a plant height with a mean of approximately 1.5 m. As an independent organism, it does not exhibit parasitic behavior, nor does it function as an epiphyte, remaining firmly rooted in a terrestrial habitat.

Aquatic :

terrestrial

Climber :

self-supporting

Epiphyte :

terrestrial

Growth form :

herb

Growth form :

forb

Parasite :

independent

Plant height mean:

1.5 m

Woodiness :

non-woody

Physiology

The physiology of Asclepia incarnata is characterized by a specialized metabolic framework designed to support its perennial growth habit and reproductive cycles. Central to its energy production is its photosynthetic pathway, which utilizes the C3 mechanism, involving the direct fixation of atmospheric carbon dioxide via the enzyme RuBisCO within the mesophyll cells. This metabolic process drives the synthesis of carbohydrates necessary for the development of its complex floral structures and milky latex. The plant's water relations and nutrient uptake are managed through an extensive root system that facilitates efficient transpiration, regulated by stomatal movements that balance gas exchange with moisture retention. Furthermore, the physiological production of cardenolides—cardiac glycosides—serves as a critical chemical defense mechanism, utilizing secondary metabolic pathways to deter herbivory while influencing the plant's overall physiological resilience.

Photosynthetic pathway :

C3

Reproduction

The reproduction of Asclepia incarnata is characterized by a specific seasonal flowering window and the production of lightweight seeds. The flowering period typically commences in July and extends through August, though the timing can be variable depending on environmental conditions. Following successful pollination, the plant produces seeds with a highly specific mass profile; the mean seed mass is approximately 0.0033 g, with individual seed weights ranging from a minimum of 0.00295 g to a maximum of 0.0044 g.

Flowering time :

Jul

Flowering time :

Aug

Seed mass max:

0.0044 g

Seed mass mean:

0.0033 g

Seed mass min:

0.00295 g

Sources: Global Inventory of Floras and Traits (GIFT)

Chemicals

Asclepias incarnata has 1 reported phytochemicals identified across 0 scientific publications and several other databases. The most consistently reported chemicals include Cardenolide.

Cardenolide

1. The Journal of animal ecology