2 Answers

Everytime it comes up , spray it with glyphosate . may take 5-10 times but it will get it eventually.

Or try amicide.

Management: Horsetail is difficult to control by cultivation because new stems regenerate from rhizome fragments and from tubers. Black plastic sheeting has been found to kill or suppress rhizomes in the upper layers of soil however, the emerging vegetative stems can penetrate some woven polypropylene mulches. Horsetail can survive periods of flooding and burning but may be sensitive to water stress in drought conditions, especially in competition with other plants.

Control measures on arable land include soil drainage, liming, deep cultivation, improvements in soil texture and persistent cutting of vegetative and spore bearing shoots. In grass, regular mowing over a period of years may eliminate horsetail.

Horsetail is not very competitive in tall crops. The lack of functional leaves may make it intolerant of shading. Horsetail does not respond as quickly as cereals to increased soil fertility.

No effective biological control agents have been found.

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