American Burnweed, Erechtites hieraciifolius

A daisy (Asteraceae) family member, American burnweed (Erechtites hieraciifolius), also known as eastern burnweed, pilewort, and fireweed, is native to North America. This fast-growing annual has seeds that can withstand harsh conditions and then germinate when conditions are favorable. A pioneer species, it is often found in forest areas following fires and disturbed open sites, roadsides, clearings, and pastures. It can grow in shallow rocky soil and tolerates cultivation. It also has a high reproductive potential due to its numerous seeds.

Native Americans used the plant to treat poison ivy and poison sumac-induced rashes. Medicinally, it has also been used as an emetic and to treat dysentery, eczema, diarrhea, and hemorrhoids. It has been used to create a blue dye for wool and cotton and, despite its intense flavor, can be eaten raw or cooked. Recent studies in Japan have found it to be efficient at assimilating atmospheric nitrogen dioxide, a greenhouse gas, and rendering it into its organic form. This may provide the possibility of using these plants as a nitrogen sink to help sequester pollutants from fossil fuels, reducing atmospheric nitrogen dioxide pollution.

American burnweed has elliptical-shaped leaves with serrated edges that have an unpleasant scent when crushed. They have brittle, grooved stems and may grow to a height of 8 to 10 feet.

Blooming in summer, their numerous panicle-like flower heads have the appearance of buds that never quite open. A white to a yellow disc of flowers is barely visible above the inch-long, green, linear bracts that enclose them. Wasps are their primary pollinator. Once pollinated, burnweed develops a puff of seeds that is reminiscent of dandelions. A cluster of white-silver hairs is attached to a small brown seed, so that the wind can quickly disperse them.

Considered a problem weed for agricultural growers of barley, oats, blueberries, and strawberries, they compete for resources and sometimes harbor crop pathogens. A short taproot with fibrous, shallow, secondary roots makes hand removal easy. Hoeing and cultivation are effective in small populations. Larger populations may require the use of broad-spectrum herbicides. Be sure to examine current product labels before applying any chemical, and for questions or assistance, contact your county extension office. It is important to remove the plants before they release their seeds.  If not, you might have thousands of seeds in the seed bank of your soil for years to come.