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Poisonous Plants: Agave spp.

Agaves is a large genus of almost 3000 plants native to hot arid regions of Mexico and Southwestern US and belongs to the asparagus family, Asparagaceae, that also includes yucca, hosta, and lily of the valley. It is a perennial producing a rosette of leaves, flowers once and then dies, but often is survived by suckers produced at the base of the stem. Although the agave resembles cactus, they are not related but are often used together in xerophytic gardens because of their similar tolerance of high temperatures and sparse rainfall. The most commonly cultivated agave is the century plant, A. americana, that usually grows 4-6’ tall and has pale yellow flowers that are carried on a spike 15-25′ tall. Various species of agave are grown for fiber, soap, sweetener, and mescal.

Description: Agaves range in size from 4” to 30’ tall and are succulents with fleshy evergreen leaves that have marginal prickles and often end in a terminal spine. The flowers are usually funnel-shaped with exerted stamens and are produced on stout stalks that arise from the basal rosette. The length of the bloom time is variable and effected by climate, but usually occurs just once in the lifetime of the plant.

Poisonous Properties: The sap of agaves contains saponin. Saponin causes inflammation of the skin to varying degrees depending on the sensitivity of the individual. Contact with the sap causes an instant burning sensation, followed by a red rash, itching welts, and blisters. Immediate removal of the sap usually stops the symptoms within a few days. The sap is also phototoxic causing skin irritation after exposure to sunlight.