About Eupatorium album L.
Eupatorium album, commonly called white thoroughwort or snowy white eupatorium, is a herbaceous perennial plant species in the Asteraceae family. It is native to the eastern and southern United States, with a distribution ranging from eastern Texas east to Connecticut, and extending inland as far north as Indiana. Like other species in the genus Eupatorium, Eupatorium album produces flowers arranged in many small white heads. Each flower head contains 4 to 5 disc florets and has no ray florets. Its flowering period runs from late June through October. This plant grows to a height of 50 to 100 cm (20 to 39 inches), making it one of the shorter species in the genus Eupatorium. Eupatorium album can hybridize with other Eupatorium species, including Eupatorium sessilifolium and Eupatorium serotinum. It has a similar appearance to Eupatorium altissimum, but can be distinguished by its flower head base bracts, which taper to a long point. Eupatorium album grows in dry, open locations including power line clearings, old fields, and eroded slopes. It cannot grow under a shady closed canopy, but it can occur in open woodland areas like pine barrens. It is commonly found in fire-dependent habitats, and its population increases in abundance after fire disturbance. There are three accepted varieties of this species: Eupatorium album var. album, which occurs across most of the species' full range; Eupatorium album var. subvenosum A. Gray, which is found in Delaware, the District of Columbia, New Jersey, and New York; and Eupatorium album var. vaseyi (Porter) Cronquist, which ranges from Alabama north to Pennsylvania.
