Conyza canadensis


Botanical description: Horseweed is an early colonizer of sunny, open urban sites with gravel or bare ground. Emerging as a series of single spikes, the plant quickly forms large monocultures that move together as wind sets into motion the top-heavy plumes and evokes a romantic meadow-like effect despite the often rubble-strewn context. Over the course of one summer, Conyza canadensis seedlings will develop into a tapering spike, four to six feet tall. In late summer, the stem branches out from an inconspicuous basal rosette of leaves to a carry an airy panicle of tiny white flowers. These flowers are often covered in a cloud of insects, providing food for small wasps, flies and bees and the occasional muskrat. The botanical name Conyza, derived from the Greek word for flea, speaks to its early use in deterring fleas from taking residence in bedding. Historically, it has been used to treat gout, menstrual issues, and kidney stones. Horseweed contains a compound that can irritate one’s nose and has been used intentionally by humans to induce sneezing as a means to relieve sinus pressure. The dried stems of horseweed are considered one of the best materials with which to make fire using the classic friction technique.



Place of Origin

North America