Horsetail

Equisetum species

The horsetail plant is one of the oldest lineages of plants on earth still living today. Fossil remains show that its ancestors once dominated prehistoric landscapes over 300 million years ago. Today, the living horsetail grows in thick clumps of hollow, jointed stems, with slim branches that give it a brush-like, pine-tree appearance. It’s a very common sight growing in damp soils all over North America, Europe, and Asia. You’ll see it lining riverbanks, ditches, and meadows, or sprouting from patches of damp ground.

Horsetail is unusual among herbs, as it has one of the highest silica contents of any plant on earth. It’s this rich silica and mineral content, which also makes the plant rigid and hard like bamboo, that gives horsetail its power and value in herbal medicine [1][2]. Traditional uses of decoctions made from the stems have focused on connective-tissue repair, bone healing, and hair and nail growth, and the minerals, especially silica, can be slowly extracted by simmering in water.

Horsetail is also a diuretic, and can help reduce water retention and support urinary-tract health [3][4][5]. European and Native American herbal traditions have used it for kidney and bladder conditions as well, but care should be taken if used over a long period of time, as it can deplete potassium.

Horsetail is edible when young, but as the plant matures it becomes too fibrous for most tastes. However, it’s true gift is in its density of minerals. It’s a living connection to both our current wetlands, as well as the ancient forests that once covered the Earth [6].

[1] Law, Chinnoi, and Christopher Exley. “New Insight into Silica Deposition in Horsetail (Equisetum arvense).” BMC Plant Biology 11 (2011): 112. https://europepmc.org/articles/PMC3160890

[2] Carneiro, Danilo Maciel, Thiago Veiga Jardim, Ymara Cássia Luciana Araújo, Ana Carolina Arantes, Andrea Cristina de Sousa, et al. “Equisetum arvense: New Evidences Supports Medical Use in Daily Clinic.” Pharmacognosy Reviews 13, no. 26 (2019): 50–58. https://www.phcogrev.com/sites/default/files/PharmacognRev-13-26-50.pdf

[3] Carneiro, Danilo Maciel, et al. “Randomized, Double-Blind Clinical Trial to Assess the Acute Diuretic Effect of Equisetum arvense (Field Horsetail) in Healthy Volunteers.” Evidence-Based Complementary and Alternative Medicine (2014): Article ID 760683. https://doi.org/10.1155/2014/760683

[4] British Herbal Medicine Association. “Horsetail.” https://bhma.info/indications/urinary-problems/horsetail/

[5] Drugs.com. “Horsetail – Uses, Benefits & Dosage.” https://www.drugs.com/npp/horsetail.html

[6] OnestopGardenShop. “Field Horsetail Plant (Equisetum arvense): Benefits, Side Effects, and Skincare Properties Explained.” https://www.onestopgardenshopco.org/post/field-horsetail-plant-equisetum-arvense-benefits-side-effects-and-skincare-properties-explained