Ageratina altissima

Species of flowering plant in the daisy family

Ageratina altissima, commonly known as white snakeroot, is a species of flowering plant in the Asteraceae family. It is native to North America and is known for its small white flowers and its toxic properties.

Description

Ageratina altissima is a perennial herb that typically grows to a height of 0.5 to 1.5 meters. The plant has opposite, simple leaves that are ovate to triangular in shape, with serrated margins. The stems are erect and branched, often with a purplish hue.

The flowers are small, white, and arranged in flat-topped clusters called corymbs. Each flower head contains numerous tiny florets. The blooming period is from late summer to fall.

Distribution and habitat

Ageratina altissima is found throughout eastern North America, from Canada to the United States. It thrives in shaded areas, such as woodlands and forest edges, and is often found in moist, rich soils.

Toxicity

The plant contains toxic compounds known as tremetol, which can cause tremetol poisoning in livestock and humans. This condition, historically known as "milk sickness," occurs when animals consume the plant and the toxin is passed through their milk. Symptoms in humans include nausea, vomiting, and muscle tremors.

Ecology

Ageratina altissima plays a role in its ecosystem by providing nectar for various pollinators, including bees and butterflies. However, its toxicity makes it less palatable to herbivores.

Cultivation and uses

While not commonly cultivated due to its toxicity, Ageratina altissima can be used in native plant gardens for its attractive flowers and ability to thrive in shaded areas.

Gallery

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  Flowers of Ageratina altissima
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  Close-up of Schizomyia eupatoriflorae on Ageratina altissima
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  Ageratina altissima plant

Related pages

• Asteraceae
• Tremetol poisoning
• Milk sickness