Milkweed facts for kids

Kids Encyclopedia Facts
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 pod
Asclepias syriaca seed pods, upper image from August and lower from December.
Milkweed sprout
Milkweed sprout, a few days after sowing
Bee on Antelope Horn-April 2015
Honeybee on antelope horn (Asclepias asperula) with pollinia attached to legs
Milkweed-in-seed2
Seeds
Monarch on milkweed (36440924066)
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.jpg Asclepias albicans Whitestem milkweed, native to the Mojave and Sonoran deserts
Asclepias amplexicaulis Blue Ridge.jpg Asclepias amplexicaulis Blunt-leaved milkweed, native to central and eastern United States
Asclepias asperula - Antelope Horns.jpg Asclepias asperula Antelope horns, native to American southwest and northern Mexico
Asclepias sp. flowers (Marshal Hedin).jpg Asclepias californica California milkweed, native to central and southern California
Asclepias cordifolia.JPG Asclepias cordifolia Heart-leaf milkweed, native to the Sierra Nevada and Cascade Range up to 2000 m.
Asclepiascryptoceras.jpg Asclepias cryptoceras Pallid milkweed, native to the western United States.
Asclepias curassavica (Mexican Butterfly Weed) W IMG 1570.jpg Asclepias curassavica Scarlet milkweed, tropical milkweed, bloodflower, bastard ipecacuanha, native to the American tropics, introduced to other continents
Asclepias curtissii (Curtiss milkweed ) (5771618293).jpg Asclepias curtissii Curtiss's milkweed, endemic to sandy areas of Florida
Asclepiaseriocarpa.jpg Asclepias eriocarpa Woollypod milkweed, native to California, Baja California, and Nevada
Asclepias erosa 5.jpg Asclepias erosa Desert milkweed, native to California, Arizona, and Baja California
Asclepias exaltata (2985661678).jpg Asclepias exaltata Poke milkweed, native to eastern North America
Asclepias fascicularis flowers 2003-06-05.jpg Asclepias fascicularis Narrow-leaf milkweed, native to Western United States
Asclepias hirtella.jpg Asclepias hirtella Tall green milkweed
Asclepias humistrata.jpg Asclepias humistrata Sandhill milkweed, native to southeastern United States
Swamp Milkweed Asclepias incarnata Flowers Closeup 2800px.jpg Asclepias incarnata Swamp milkweed, native to wetlands of North America
Asclepias involucrata
Asclepias lanceolata plant.jpg Asclepias lanceolata Lanceolate milkweed (Cedar Hill milkweed), native to coastal plain of eastern United States from Texas to New Jersey
Asclepias linaria.jpg Asclepias linaria Pine needle milkweed, native to Mojave and Sonoran deserts
Asclepias linearis Slim milkweed
Asclepiasmeadii.jpg Asclepias meadii Mead's milkweed, native to midwestern United States
Asclepias nivea
Asclepias nyctaginifolia.jpg Asclepias nyctaginifolia Mojave milkweed, native to the American southwest
Asclepias obovata Pineland milkweed
Purple Milkweed Asclepias purpurascens Head.jpg Asclepias purpurascens Purple milkweed, native to eastern, southern, and midwestern United States
Asclepias quadrifolia 001.jpg Asclepias quadrifolia Four-leaved milkweed, native to eastern United States and Canada
BB-3386 Asclepias rubra.png Asclepias rubra Red milkweed
Asclepias solanoana.jpeg Asclepias solanoana Serpentine milkweed, native to northern California
R27182818 milkweed img 0312.jpg Asclepias speciosa Showy milkweed, native to western United States and Canada
Asclepias subulata flowers 2.jpg Asclepias subulata Rush milkweed, leafless milkweed, native to southwestern North America
Asclepias subverticillata.jpg Asclepias subverticillata Horsetail milkweed
Asclepias sullivantii.jpg Asclepias sullivantii Sullivant's milkweed
Common milkweed-tracy.jpg Asclepias syriaca Common milkweed
Asclepias texana.jpg Asclepias texana Texas milkweed
Butterfly Weed Asclepias tuberosa Umbel.jpg Asclepias tuberosa Butterfly weed, pleurisy root
Asclepias uncialis lg.jpg Asclepias uncialis Wheel milkweed
Asclepias variegata.jpg Asclepias variegata White milkweed
Asclepias verticillata (3197723098).jpg Asclepias verticillata Whorled milkweed
Asclepias vestita Woolly milkweed
Asclepias viridiflora NPS-1.jpg Asclepias viridiflora Green milkweed
Asclepias viridis 1.jpg Asclepias viridis Green antelopehorn, spider milkweed
Asclepias welshii 1.jpg Asclepias welshii Welsh's milkweed

Milkweed Facts for Kids. Kiddle Encyclopedia.