Horsetail Fern erradication - Ask Extension
I have had some horsetail fern slowly (and now not slowly) spreading in my (1/4 acre) yard in West Salem. I've know to dig down to try and get the roo...
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Horsetail Fern erradication #869805
Asked May 23, 2024, 2:46 PM EDT
I have had some horsetail fern slowly (and now not slowly) spreading in my (1/4 acre) yard in West Salem. I've know to dig down to try and get the root and runners, I've tried (once or twice) to use Roundup (which I occassionally use judiciously in my yard). With our wet spring, the horsetail fern has taken off. I recently read that its VERY HARD to eliminate, and that it has the spores which of course aid in spreading! My reading suggested cutting off at the ground (I think) and elimiating its source of sunlight (cover with a board or rock??). My reading also emphasized disinfecting tools which I have not done before. Do you have any further suggestions/corrections? And is there anything I can spray to help to eradicate it.
Polk County Oregon
Expert Response
Dear Gardener,
Thank you for contacting Ask Extension about horsetail control. This is one of the toughest weeds to eradicate as demonstrated by the fact that it has been around for millions of years. Unfortunately, there are no effective chemical controls available for home use.
The link below is for an article from the Extension Service in Maine. It gives a good description of what not to do as well as the most effective way to control it. The method is to improve drainage, raise the soil pH, and raise the nutritional content of the soil.
Raised beds will help provide better drainage. Applying dolomite lime can raise the pH, but first make sure that your plants can tolerate a higher pH. You can fertilize, but I suggest using a slow-release fertilizer and applying at half the directed strength.
Eliminating light is a common recommendation to control weeds, but trying to cover horsetail is not usually practical due to the extensive root system. Pulling it may make the situation worse, but cutting it to the ground regularly will help prevent it from photosynthesizing. The effect may be primarily aesthetic, but cutting will prevent the spread of seeds (spores) in early spring.
Disinfecting tools is usually recommended to prevent spreading plant diseases, but it certainly would not hurt to clean them with witch hazel or rubbing alcohol.
I hope this information is helpful. Please write again if you have more questions.
https://www.maine.gov/dacf/php/gotpests/weeds/factsheets/horsetail-swanson.pdf
Thank you for contacting Ask Extension about horsetail control. This is one of the toughest weeds to eradicate as demonstrated by the fact that it has been around for millions of years. Unfortunately, there are no effective chemical controls available for home use.
The link below is for an article from the Extension Service in Maine. It gives a good description of what not to do as well as the most effective way to control it. The method is to improve drainage, raise the soil pH, and raise the nutritional content of the soil.
Raised beds will help provide better drainage. Applying dolomite lime can raise the pH, but first make sure that your plants can tolerate a higher pH. You can fertilize, but I suggest using a slow-release fertilizer and applying at half the directed strength.
Eliminating light is a common recommendation to control weeds, but trying to cover horsetail is not usually practical due to the extensive root system. Pulling it may make the situation worse, but cutting it to the ground regularly will help prevent it from photosynthesizing. The effect may be primarily aesthetic, but cutting will prevent the spread of seeds (spores) in early spring.
Disinfecting tools is usually recommended to prevent spreading plant diseases, but it certainly would not hurt to clean them with witch hazel or rubbing alcohol.
I hope this information is helpful. Please write again if you have more questions.
https://www.maine.gov/dacf/php/gotpests/weeds/factsheets/horsetail-swanson.pdf
Dear Diana,
Here is a copy of my first response on horsetail. Gypsum does not raise the soil pH and it tends to reduce nutrients in the soil. It
is sometimes used to loosen heavy clay soils or to counteract too many salts (including fertilizers) in the soil. I would not recommend using gypsum.
You could use lime in the areas where the horsetail ferns are more prolific, but keep in mind that soil amendments do not necessarily stay in one place. It may migrate into nearby garden beds through the groundwater. You're in a difficult situation since you need two different types of soil, so you may have to choose your battles.
Best regards,
Lynne
May 24, 2024
Thank you for contacting Ask Extension about horsetail control. This is one of the toughest weeds to eradicate as demonstrated by the fact that it has been around for millions of years. Unfortunately, there are no effective chemical controls available for home use.
The link below is for an article from the Extension Service in Maine. It gives a good description of what not to do as well as the most effective way to control it. The method is to improve drainage, raise the soil pH, and raise the nutritional content of the soil.
Raised beds will help provide better drainage. Applying dolomite lime can raise the pH, but first make sure that your plants can tolerate a higher pH. You can fertilize, but I suggest using a slow-release fertilizer and applying at half the directed strength.
Eliminating light is a common recommendation to control weeds, but trying to cover horsetail is not usually practical due to the extensive root system. Pulling it may make the situation worse, but cutting it to the ground regularly will help prevent it from photosynthesizing. The effect may be primarily aesthetic, but cutting will prevent the spread of seeds (spores) in early spring.
Disinfecting tools is usually recommended to prevent spreading plant diseases, but it certainly would not hurt to clean them with witch hazel or rubbing alcohol.
I hope this information is helpful. Please write again if you have more questions.
https://www.maine.gov/dacf/php/gotpests/weeds/factsheets/horsetail-swanson.pdf
Here is a copy of my first response on horsetail. Gypsum does not raise the soil pH and it tends to reduce nutrients in the soil. It
is sometimes used to loosen heavy clay soils or to counteract too many salts (including fertilizers) in the soil. I would not recommend using gypsum.
You could use lime in the areas where the horsetail ferns are more prolific, but keep in mind that soil amendments do not necessarily stay in one place. It may migrate into nearby garden beds through the groundwater. You're in a difficult situation since you need two different types of soil, so you may have to choose your battles.
Best regards,
Lynne
May 24, 2024
Thank you for contacting Ask Extension about horsetail control. This is one of the toughest weeds to eradicate as demonstrated by the fact that it has been around for millions of years. Unfortunately, there are no effective chemical controls available for home use.
The link below is for an article from the Extension Service in Maine. It gives a good description of what not to do as well as the most effective way to control it. The method is to improve drainage, raise the soil pH, and raise the nutritional content of the soil.
Raised beds will help provide better drainage. Applying dolomite lime can raise the pH, but first make sure that your plants can tolerate a higher pH. You can fertilize, but I suggest using a slow-release fertilizer and applying at half the directed strength.
Eliminating light is a common recommendation to control weeds, but trying to cover horsetail is not usually practical due to the extensive root system. Pulling it may make the situation worse, but cutting it to the ground regularly will help prevent it from photosynthesizing. The effect may be primarily aesthetic, but cutting will prevent the spread of seeds (spores) in early spring.
Disinfecting tools is usually recommended to prevent spreading plant diseases, but it certainly would not hurt to clean them with witch hazel or rubbing alcohol.
I hope this information is helpful. Please write again if you have more questions.
https://www.maine.gov/dacf/php/gotpests/weeds/factsheets/horsetail-swanson.pdf
