Common Horsetail
Equisetum arvense
Last reviewed: June 2026
Common Horsetail (Equisetum arvense) is a primitive fern native across most US states that produces spores in spring from March to May. This ancient plant thrives in moist soils and partial shade conditions.
Common Horsetail (Equisetum arvense) is not on the ASPCA Animal Poison Control Center toxic plant list for dogs or cats (aspca.org (opens in new tab), last reviewed 2026-05-21). If your pet shows symptoms after eating any plant, call the ASPCA at (888) 426-4435.
Common Horsetail is listed as toxic to grazing livestock (cattle, sheep, and goats) at a moderate level by the USDA PLANTS Database (opens in new tab). This is a livestock indicator and is separate from pet toxicity.
Light
part shade
Water
medium
Size
4"–24" H × 2"–12" W
Bloom
Mar, Apr, May
Native to
AL, AR, AZ, CA and 42 more states
Browse plants for this ecoregion
Common horsetail is an ancient fern ally that produces distinctive jointed, segmented stems resembling miniature bamboo. This primitive plant spreads by underground rhizomes and produces separate fertile stems with cone-like structures in spring, followed by sterile green photosynthetic stems through summer.
Growing Common Horsetail
Grow Common Horsetail in part shade and medium water. Mature plants reach 4 to 24 inches tall and spread 2 to 12 inches wide. Expect high maintenance to keep it looking intentional in a front yard.
In an HOA neighborhood
Common Horsetail takes more care to keep looking intentional in a front yard. Maintenance level: high. Consider it for backyard or mid-zone beds rather than the street edge.
Works well in: backyard only.
- Aggressive spreading habit can invade other plantings
- Unusual prehistoric appearance may seem unkempt
- Difficult to control once established
Wildlife value
Horsetails provide minimal wildlife value as they do not produce flowers for pollinators and are generally not eaten by wildlife due to their high silica content and primitive structure.
Common questions
- When does Common Horsetail reproduce?
- Common Horsetail produces spores from March through May, releasing them from cone-like structures called strobili that appear on separate fertile stems.
- Where is Equisetum arvense native in the United States?
- Common Horsetail is native to most US states including the Pacific Northwest, Great Plains, Great Lakes region, and eastern states from Maine to Georgia, with scattered populations in the Southwest.
- What growing conditions does Common Horsetail prefer?
- This species grows best in consistently moist to wet soils in partial shade to full shade conditions, though it can tolerate some morning sun.
- Is Common Horsetail toxic to dogs?
- Common Horsetail is not on the ASPCA Animal Poison Control Center toxic plant list for dogs (aspca.org).
- Is Common Horsetail toxic to cats?
- Common Horsetail is not on the ASPCA Animal Poison Control Center toxic plant list for cats (aspca.org).
- Is Common Horsetail toxic to livestock?
- Common Horsetail is listed as toxic to grazing livestock such as cattle, sheep, and goats (moderate severity) by the USDA PLANTS Database. This is separate from pet (dog and cat) toxicity.
- Is Common Horsetail HOA-friendly?
- Common Horsetail takes more care to look intentional in a front yard. Consider it for backyard or mid-zone beds rather than the street edge.
Native range data from the USDA PLANTS Database and regional native plant society lists. Pollinator and host plant associations compiled from GBIF, iNaturalist, and published ecological literature.
Ready to grow Common Horsetail? Add it to your garden in Pollinator Patch to track it and get season-by-season care guidance.
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