Equisetum praealtum

Tall Scouring Rush is an herbaceous, non-flowering, evergreen perennial in the Equisetaceae (horsetail) family.  It is native to North America, Greenland, Northeast China, Russian Far East, Japan, and Central America.  It is distributed in all continental U.S. states and has been introduced to Belgium and Taiwan.  Stems have rough silica-containing ridges, making it unappealing to deer and other herbivores.  Although this plant is very similar to E. hyemale, it is sometime classified as a separate species due to morphological differences in height, color, stem diameter and number of ridges. It forms large, dense colonies of upright, reed-like, unbranched stalks up to 11 feet tall. Stems are conspicuously jointed, where small, dark, triangular scale-like leaves are arranged in a ring around each joint. It forms both fertile and infertile shoots. This plant reproduces by means of a spore-bearing cone that forms at the tip of fertile stems. Spores are released in early to mid-summer. Plants also spread by means of a deep network of rhizomes and fibrous secondary roots.  It prefers full to partial sun and is found in moist or wet habitats with sandy or gravely soil such as wetlands, ditches, riparian areas, alluvial flats, swamps, ponds and other areas with standing water.  It is often found in areas containing limestone.  This plant is sometimes available from nurseries and is best suited as a potted specimen to prevent aggressive, invasive spread if planted in-ground.

Insects, Diseases and Other Plant Problems:   No serious problems. It is an aggressive spreader by rhizomes.