Milkweed facts for kids

Quick facts for kids Milkweeds
Asclepias + ant feeding on nectar
Scientific classification
Kingdom:	Plantae
(unranked):	Angiosperms
(unranked):	Eudicots
(unranked):	Asterids
Order:	Gentianales
Family:	Apocynaceae
Subfamily:	Asclepiadoideae
Genus:	Asclepias L.
Species
See text.

Asclepias syriaca seed pods, upper image from August and lower from December.

Milkweed sprout, a few days after sowing

Honeybee on antelope horn (Asclepias asperula) with pollinia attached to legs

Seeds

Monarch Butterfly on Milkweed

The milkweeds, Asclepias (L. 1753), are a genus of herbaceous perennial, dicotyledonous plants that contains over 140 known species.

Milkweeds are an important nectar source for bees and other nectar eaters, and a food source for caterpillars. The weeds are eaten by caterpillars of the monarch butterfly and its relatives, and by other herbivorous insects (such as beetles, and true bugs). These insects are able to feed on the plants despite their chemical defences. Milkweed is named after its milky sap, which contains alkaloids, latex, and several other complex compounds. Some species are toxic.

Pollination in this genus is accomplished in an unusual manner, as the pollen is grouped into pollen sacs. The feet or mouthparts of flower visiting insects such as bees, wasps and butterflies, slip into one of the five slits in each flower formed by adjacent anthers. The bases of the pollinia then mechanically attach to the insect, pulling a pair of pollen sacs free when the pollinator flies off. Pollination is effected by the reverse procedure in which one of the pollinia becomes trapped within the anther slit.

Milkweeds have three defenses to limit damage by caterpillars and other insects: hairs on the leaves, toxins, and latex fluids. Some more recent milkweed species grow faster than older species. They have the potential to grow faster than caterpillars can eat them. Caterpillars which eat milkweeds, and their adult butterflies, may be protected by the foul taste of the milkweed chemicals. Such butterflies and caterpillars usually show warning colors (see mimicry#warning coloration).

Species

Some Asclepias species:

	Asclepias albicans	Whitestem milkweed, native to the Mojave and Sonoran deserts
	Asclepias amplexicaulis	Blunt-leaved milkweed, native to central and eastern United States
	Asclepias asperula	Antelope horns, native to American southwest and northern Mexico
	Asclepias californica	California milkweed, native to central and southern California
	Asclepias cordifolia	Heart-leaf milkweed, native to the Sierra Nevada and Cascade Range up to 2000 m.
	Asclepias cryptoceras	Pallid milkweed, native to the western United States.
	Asclepias curassavica	Scarlet milkweed, tropical milkweed, bloodflower, bastard ipecacuanha, native to the American tropics, introduced to other continents
	Asclepias curtissii	Curtiss's milkweed, endemic to sandy areas of Florida
	Asclepias eriocarpa	Woollypod milkweed, native to California, Baja California, and Nevada
	Asclepias erosa	Desert milkweed, native to California, Arizona, and Baja California
	Asclepias exaltata	Poke milkweed, native to eastern North America
	Asclepias fascicularis	Narrow-leaf milkweed, native to Western United States
	Asclepias hirtella	Tall green milkweed
	Asclepias humistrata	Sandhill milkweed, native to southeastern United States
	Asclepias incarnata	Swamp milkweed, native to wetlands of North America
	Asclepias involucrata
	Asclepias lanceolata	Lanceolate milkweed (Cedar Hill milkweed), native to coastal plain of eastern United States from Texas to New Jersey
	Asclepias linaria	Pine needle milkweed, native to Mojave and Sonoran deserts
	Asclepias linearis	Slim milkweed
	Asclepias meadii	Mead's milkweed, native to midwestern United States
	Asclepias nivea
	Asclepias nyctaginifolia	Mojave milkweed, native to the American southwest
	Asclepias obovata	Pineland milkweed
	Asclepias purpurascens	Purple milkweed, native to eastern, southern, and midwestern United States
	Asclepias quadrifolia	Four-leaved milkweed, native to eastern United States and Canada
	Asclepias rubra	Red milkweed
	Asclepias solanoana	Serpentine milkweed, native to northern California
	Asclepias speciosa	Showy milkweed, native to western United States and Canada
	Asclepias subulata	Rush milkweed, leafless milkweed, native to southwestern North America
	Asclepias subverticillata	Horsetail milkweed
	Asclepias sullivantii	Sullivant's milkweed
	Asclepias syriaca	Common milkweed
	Asclepias texana	Texas milkweed
	Asclepias tuberosa	Butterfly weed, pleurisy root
	Asclepias uncialis	Wheel milkweed
	Asclepias variegata	White milkweed
	Asclepias verticillata	Whorled milkweed
	Asclepias vestita	Woolly milkweed
	Asclepias viridiflora	Green milkweed
	Asclepias viridis	Green antelopehorn, spider milkweed
	Asclepias welshii	Welsh's milkweed

Images for kids

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  A monarch butterfly on swamp milkweed

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  Male Pepsis grossa, a typical milkweed-pollinating wasp

See also

In Spanish: Asclepias para niños