Scientific Name: Asclepias asperula
Common Names: Spider Milkweed, Antelope Horns, Antelopehorn Milkweed, Spider Antelope-horns, Green-flowered Milkweed, Immortal
Growth Habit: Herb/Forb
Arizona Native Status: Native
Habitat: Desert, Upland, Mountain. This attractive wildflower grows in sunny, open locations in dry, rocky and sandy soil.
Flower Color: Pale green with white and maroon
Flowering Season: Spring, Summer
Height: Up to 3 feet (1 m) tall, but usually half that
Description: The flowers are tightly clustered in rounded, up to 3 inch (7.6 cm) wide umbels. The individual flowers have 5 upcurved, point-tipped, green petals and 5 spreading and upcurved, magenta and white hoods. The flowers are followed by erect, green and maroon-tinged, narrowly teardrop-shaped, up to 4 inch (10 cm) long follicles (fruit). The leaves are green, finely haired, alternate or irregularly grouped, narrowly lance-shaped, and up to 8 inches (20 cm) long. The stems are upright or sprawling, unbranched, and covered with fine, short hairs. The plants ooze milky white sap if damaged.
Butterfly Plant – The flowers attract butterflies. The plants are a food source for Queen (Danaus gilippus) butterflies.
Poisonous – The plants are poisonous.
Kingdom: Plantae – Plants
Subkingdom: Tracheobionta – Vascular plants
Superdivision: Spermatophyta – Seed plants
Division: Magnoliophyta – Flowering plants
Class: Magnoliopsida – Dicotyledons
Family: Asclepiadaceae – Milkweed family
Genus: Asclepias L. – milkweed
Species: Asclepias asperula (Decne.) Woodson – spider milkweed
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