American Burnweed - Weed of the Week

A Late Summer Surprise

Have you ever had a tall weed that grew so quickly it seemed to appear in your yard overnight? There’s a good chance that speedy weed is American burnweed, and your yard is probably not the only one it has popped up in. American burnweed (Erechtites hieraciifolius), also known as fireweed, is a fast-growing, annual weed commonly spotted in gardens and fields around West Virginia in late August and early September.

American Burnweed Identification and Growth Habits

This shallow rooted, herbaceous plant grows under a wide range of conditions in disturbed habitats. The stems are brittle with large basal leaves and deeply serrated upper leaves. It is a relatively benign weed, prone to removal by hand thanks to shallow, fibrous roots attached to a short taproot. It produces numerous cup-shaped flowers in the axil, enclosing densely arranged disc florets in a cylindrical calyx. When the flowers bloom, they display a cluster of silvery hairs attached to tiny seeds. This weed is considered to be native to the forest zones of North America and can stretch to 8 to 10 feet high under ideal growing conditions.

American burnweed has several medicinal properties. The oil derived from the plant is used to treat wounds, hemorrhages, poison ivy rashes and other ailments, such as piles. This plant is particularly efficient in assimilating atmospheric nitrogen dioxide, an important greenhouse gas, and rendering it to its organic form.

As a weed, it can compete and interfere with certain crops, such as blueberries and strawberries, bringing about economic losses. It can also reduce the aesthetic attributes of the landscape where it’s growing. The scent of a crushed plant can be unpleasant to some, but the sap does not trigger any rashes or other allergic reactions.

Control of American Burnweed

American burnweed can easily be hand weeded, taking advantage of its shallow root system. Hoeing or cultivation is also effective to control smaller populations. Large populations can be controlled by applying broadleaf herbicides containing 2,4-D and triclopyr, other broad-spectrum selective herbicides or a non-selective herbicide, such as glyphosate or glufosinate.