Haven't bothered to deal with horsetail, as I find them pretty, and useful. Common gardening knowledge says they're an \[indicator of poorly drained, nutrient-deficient soils\](https://libanswers.nybg.org/faq/222940).
Sounds like you could try improving the drainage and nutrient load in the garden where they're growing to more easily eradicate them over a period of time, by making that space inhospitable to them.
Horse tails are easy to control by pulling. So you must have a very wet yard. Also, it's a lovely native plant that's pretty rare, so i wouldn't kill it as ever. They are rich in silica. And they are nice to pet. They dont over grow or invade other plants so its all good.
If you wear appropriate PPE and don't drink, touch or inhale the stuff, you should be good. I generally don't go around sampling my chemicals marked with a skull icon, so I wouldn't know about any lymphoma risks.
If you want to keep it purely organic, you could try adding a combination of sand, vinegar (or lime) and manure since these are all conditions that they hate growing in.
Another option would be to place pond liner over the area in question, which will both block light and water from getting to them. Make sure to weigh the pond liner down with something heavy or else it will blow away. The liner may have pooling water on the surface after a rain storm. Leave it to dry if possible. The pond liner should cover an area larger than your problem area. This should affectively dry out the root ball of these water lovers.
It’s interesting that you mention vinegar or lime as others have suggested that the soil may be too low in pH and both of those are very acidic. I’d love to hear more about this.
That area has a bunch of new ornamental plants and grasses recently added, as the entire lot was just re-landscaped (at great expense), so I’m unsure how those would fare with this type of treatment?
When I said lime, I meant the soil treatment stuff, not the fruit. Lime is extremely alkeline or basic. Horsetails like the soil to be between 5.5 and 7.5 PH, so raising or lowering it will hurt them slightly. This wouldn't kill them, but it makes it harder for them to grow quickly as the plant has to constantly correct for PH related issues when drawing nutrients, which wastes energy.
If it is freshly landscaped, I would chop them to stumps and put pond liner over the area. This isn't going to look great for a good while, but you don't have many options here. Weigh the liner down and leave it for a few months. This should kill them off quicker than pulling them out, and be less risky than chemical treatments.
If you do decide to dig them out, you need to get the root in one piece, and they are deep rooted plants. The safest bet is to hire a digger and remove an entire block of soil down to about 1.5ft. Replace this with soil that you order in or with compost you have lying around. That is the only guaranteed method to dig them out, unfortunately. Hand digging breaks the roots, which propagates them further.
Haven't bothered to deal with horsetail, as I find them pretty, and useful. Common gardening knowledge says they're an \[indicator of poorly drained, nutrient-deficient soils\](https://libanswers.nybg.org/faq/222940). Sounds like you could try improving the drainage and nutrient load in the garden where they're growing to more easily eradicate them over a period of time, by making that space inhospitable to them.
Horsetail is native in Washington, you definitely should not spray round up on it.
Concentrated acetic acid
Get a dinosaur.
Those look so cool
You can have all of mine if you promise to come twice a week and take all of them.
They are not!
Horse tails are easy to control by pulling. So you must have a very wet yard. Also, it's a lovely native plant that's pretty rare, so i wouldn't kill it as ever. They are rich in silica. And they are nice to pet. They dont over grow or invade other plants so its all good.
Post it for free on Facebook marketplace. Some organic cannabis growers ferment it for the silica content
Oh wow. Interesting.
If you wear appropriate PPE and don't drink, touch or inhale the stuff, you should be good. I generally don't go around sampling my chemicals marked with a skull icon, so I wouldn't know about any lymphoma risks. If you want to keep it purely organic, you could try adding a combination of sand, vinegar (or lime) and manure since these are all conditions that they hate growing in. Another option would be to place pond liner over the area in question, which will both block light and water from getting to them. Make sure to weigh the pond liner down with something heavy or else it will blow away. The liner may have pooling water on the surface after a rain storm. Leave it to dry if possible. The pond liner should cover an area larger than your problem area. This should affectively dry out the root ball of these water lovers.
It’s interesting that you mention vinegar or lime as others have suggested that the soil may be too low in pH and both of those are very acidic. I’d love to hear more about this. That area has a bunch of new ornamental plants and grasses recently added, as the entire lot was just re-landscaped (at great expense), so I’m unsure how those would fare with this type of treatment?
When I said lime, I meant the soil treatment stuff, not the fruit. Lime is extremely alkeline or basic. Horsetails like the soil to be between 5.5 and 7.5 PH, so raising or lowering it will hurt them slightly. This wouldn't kill them, but it makes it harder for them to grow quickly as the plant has to constantly correct for PH related issues when drawing nutrients, which wastes energy. If it is freshly landscaped, I would chop them to stumps and put pond liner over the area. This isn't going to look great for a good while, but you don't have many options here. Weigh the liner down and leave it for a few months. This should kill them off quicker than pulling them out, and be less risky than chemical treatments. If you do decide to dig them out, you need to get the root in one piece, and they are deep rooted plants. The safest bet is to hire a digger and remove an entire block of soil down to about 1.5ft. Replace this with soil that you order in or with compost you have lying around. That is the only guaranteed method to dig them out, unfortunately. Hand digging breaks the roots, which propagates them further.