Hi Reed.  Thanks for contacting the UVM Extension Master Gardener helpline.

You don't say what kind of horsetail you have but in Vermont, I'm guessing you have Mares' Tails or Equisetum arvense.  Regardless, there are three basic rules for managing horsetail (Equisetum):

1. Test the soil and adjust pH and fertility as recommended. (see https://www.uvm.edu/extension/mastergardener/gardening-resources and scroll down to "Soil and Soil Health" for various information on soil testing and the instructions for submitting a sample to the UVM Soil Testing Lab.)
2. Horsetail likes wet conditions so if you can, improve drainage or adjust your irrigation practices to focus on just watering desirable plants (soaker hose or a drip irrigation system could help).
3. Avoid tillage, since horsetail spreads by rhizome.

Equisetum is one of the earliest plant forms still around today.  It thrived in the swamps/mires with the dinosaurs and still loves wet/boggy places.  To get rid of it, you'll need to dry out your growing area a bit.  Here are a few links that may help you understand what's going on and additional suggestions for suppression.
https://libanswers.nybg.org/faq/222940
https://extension.umaine.edu/gardening/2021/06/01/horsetail/
https://www.canr.msu.edu/resources/field-horsetail-a-plant-as-old-as-time

I hope this information is helpful.  Good luck!