Horse tail weed control
Horsetail (Equisetum spp) is an ancient (and persistent) species of plant that is often difficult to deal with, especially with other desirable plants in immediate vicinity. The key is to be able to make the area less hospitable to Horsetail. It likes low pH soil and wetter soils so you want to raise the pH and cause the soil to hold less water. You can add dolomitic lime to the soil to raise the pH unless the plants, bushes in the area also are acid-loving (low pH).
Herbicides generally are not effective as they will just kill the aboveground portion, but leave the roots to send up new shoots. You should cut the Horsetail to the ground frequently. Remove the pieces and place in the trash because each piece is capable of starting a new Horsetail plant. You will probably have to do this over multiple years in order to eliminate the Horsetail.