Knowledgebase
Horsetail Control #871266
Asked June 03, 2024, 10:31 AM EDT
New York County New York
Expert Response
Hi Blake,
Shannon here from the CCE Ulster Master Gardener volunteer team.
I am assuming you have Equisetum arvense, also known as field horsetail. It's always good to confirm the identification before taking action because knowing your enemy is important.
If you do have Equisetum arvense, you are facing a dynamic adversary. I have only limited personal experience with this plant, but I reviewed some resources for you, included below. In summary, DO NOT attempt to till or dig them out, as they will re-sprout from cuttings. Usually smothering a sun-loving plant will hasten its end, but no luck, horsetail loves poor, moist soils and can thrive in poor light.
It is recommended to take a multi-pronged approach: 1) remove the asparagus-like spore-spreading shoots in the spring (the spores contribute to the spread) by cutting at the base, AND remove new growth of the green stems that appear later. Carefully dispose of cuttings in the garbage to avoid more spread. 2) Improve drainage by removing anything contributing to moisture retention around the plants. 3) *Improve* soil nutrient density by adding compost or fertilizers. It sounds counterintuitive but horsetail is one of the odd plants that prefers infertile soils. You can also try to increase soil PH by adding lyme. Be thoughtful not to add lyme and compost or fertilizer at the same time... they'll offset each other.
If you want to just limit its growth rather than remove entirely, i have seen folks use large rocks to limit its roots from creeping . But as you've probably already seen, it will creep many feet. If your horsetail is near something else you value more, it may be better to try to remove it entirely than fight it every year.
Good luck!!
https://www.maine.gov/dacf/php/gotpests/weeds/factsheets/horsetail-swanson.pdf
