Amianthium muscitoxicum (Walter) A. Gray

Fly Poison


CC = 10
CW = 0
MOC = 13

© SRTurner

Family - Liliaceae

Habit - Perennial forb, from a bulb.

Stems - 30-100 cm, erect, unbranched, glabrous. Plant lacks odor of onion or garlic.

Amianthium_muscitoxicum_stem.jpg Aerial stems with greatly reduced leaves.

© SRTurner

Amianthium_muscitoxicum_cauline_leaf.jpg Aerial stem and leaf.

© DETenaglia

Leaves - Mostly basal, to 45 cm, linear, straplike, weakly pleated longitudinally. Stem leaves greatly reduced.

Amianthium_muscitoxicum_leaves.jpg Basal leaves.

© SRTurner

Inflorescences - Dense terminal racemes of numerous flowers. Flower stalks 12-18 mm long, longer than the flowers, elongating in fruit, subtended by small bracts.

Amianthium_muscitoxicum_inflorescence.jpg Inflorescences.

© SRTurner

Amianthium_muscitoxicum_bracts.jpg Bracts on infructescence.

© SRTurner

Flowers - Perianth 2.5-4.5 mm long, the sepals and petals free, white, turning yellow to green to purplish tinged after flowering. Stamens 6. Styles 3, each with a small stigma. Ovary superior, with 3 locules, each with 2 ovules

Amianthium_muscitoxicum_flowers.jpg Flowers.

© SRTurner

Amianthium_muscitoxicum_flower.jpg Flower.

© DETenaglia

Fruits - Ovoid, deeply 3-lobed capsules; lobes beaked with persistent styles.

Amianthium_muscitoxicum_fruits.jpg Young fruits.

© SRTurner

Amianthium_muscitoxicum_fruit.jpg Young fruit.

© SRTurner

Flowering - May - July.

Habitat - Mesic upland forests, lower slopes of ravines, north-facing slopes. Typically on acid substrates.

Origin - Native to the U.S.

Lookalikes - None when flowering.

Other info. - This striking species can be found mainly in the most southern counties of Missouri but a few disjunct populations are found in counties along the Missouri River. It is more common in southeastern states and into parts of New England. The plant can be identified by its long, thin basal leaves, and its dense, cylindrical inflorescence of many small, white flowers. The flowers typically change from white to yellow or even purplish with age.

A. muscitoxicum is a toxic species which contains many alkaloids. Cattle have been killed from eating the plant. An alternate name is Zigadenus muscitoxicus (Walter) Regel. The classification of these plants has been somewhat controversial, with some authors placing them into the family Melanthiaceae.

Photographs taken in the Appalachicola National Forest, FL., 3-30-05 (DETenaglia); also at Poison Hollow, Howell County, MO, 6-4-2017 and 6-11-2021 (SRTurner).