Eryngium yuccifolium
Eryngium yuccifolium, known as rattlesnake master, button eryngo, and button snake-root, is a perennial herb of the parsley family native to the tallgrass prairies of central and eastern North America. It grows from Minnesota east to Ohio and south to Texas and Florida, including a few spots in Connecticut, New Jersey, Maryland, and Delaware. There are two varieties found in the wild, the northern rattlesnake master and the southern rattlesnake master.
Name
The common name "rattlesnake master" is attributed to early European pioneers erroneously believing the plant to be an antidote for rattlesnake venom based upon Native Americans' various medicinal uses of the plant. The species name yuccifolium "yucca-leaved" was given because its leaves resemble those of yuccas.Description
The leaves are stiff, long and narrow with a sharp tip, long but only broad. They are bluish-green, and covered in a waxy coating. On the edges are regularly spaced bristles or spines. The root system consists of a central taproot surrounded by thick fleshy fibrous roots.It grows up to tall, with 10–40 dense, ball-shaped umbels of flowers produced at the top of each stem. Each of these condensed umbels is in diameter, resembling flowerheads. Individual flowers in the umbels are small, 3–4 mm in diameter, with greenish-white or bluish-white petals and a faint honey-like scent. Underneath each flower is a spiny green bract, and underneath each flower cluster is a small star-like rosette of spiny bracts. The flowers are produced in July and August.
After the flowerbuds open, the pollen matures and is released two to three days before the stigmas become receptive. This encourages cross-pollination by making it unlikely that a given flower's pollen will fertilize the stigma of the same flower. Rattlesnake master has unusually high seed set.
Distribution and habitat
Eryngium yuccifolium var. yuccifolium, the northern variety, is distributed widely throughout the eastern, midwestern, and southeastern United States. It grows in pine savannas, pine flatwoods over loamy or clay soils, wet to dry prairies, olivine barrens, diabase barrens and glades, and other open sites with at least periodic moisture.Eryngium yuccifolium var. synchaetum, the southern variety, is endemic to the southeastern Coastal Plain, from southeast North Carolina to south Florida and west across the Gulf Coastal Plain. It is found in wet savannas, particularly those over calcareous clay soils.
Ecology
In remnant natural areas, Eryngium yuccifolium is fairly intolerant of anthropogenic disturbance. It readily establishes when planted in prairie restorations.The flowers attract many insects, including short and long-tongued bees, flies, beetles, and butterflies, but most numerous of all are wasps. It is a larval host to the rare rattlesnake-master borer moth.
E. yuccifolium is mostly self-pollinated, but is recognized to be of special value to native bees because it attracts large numbers of them for pollination.
Fire is known to facilitate the spread of E. yuccifolium, with establishment of its seedlings increasing because of fire. It can increase in overall abundance in response to disturbance from fire.