Scouring rush

Encyclopedia Article

Scouring rush               Equisetum hyemale (L.)

Family: Equisetaceae                                                                   
Life cycle: Perennial, reproduces by spores and rhizomes
Native status: Native
Habitat: Wet areas, often found in drainage ditches      

General description: Tall, slender unbranched stems that reach heights of four feet. Stems are hollow, segmented, and rough surfaced. Leaves are reduced to scales at the internodes.  The fertile and sterile stems are similar, with the fertile stems topped with a spore-producing cone.

Key ID traits: Segmented stems that can be pulled apart at the nodes. Nodes have a gray band

Similar species: Field horsetail (Equisetum arvense) produces two distinct types of shoots.  The fertile shoots develop in the spring and are short-lived. They are light brown and 6 to 12 inches tall. The sterile shoots resemble miniature pine trees, approximately 10 to 20 inches tall.

Miscellaneous: Scouring rush has numerous common names, including snakeweed, skeletonweed, jointgrass, etc. The equisetums are considered living fossils since they are relics of the Carboniferous period (325 million years ago). The reduction in tillage and perhaps other factors have led to an increase in the encroachment of scouring rush into crop fields. Most herbicides used in corn and soybean production have little effect on the species (related article).

Stems and spore producing sporobili of scouring rush.  Leaves are reduced to the small scales at stem nodes.

Scouring rush invading crop field via rhizome growth from patch in adjacent road ditch.