I have them also and I keep pulling them out because they grow all over my flower garden. Someone told me to sell my house because ill never get rid of them lol.

I have no personal experience with horsetail but did a lot of research for an elderly relative that had a horsetail problem.

Since you garden organically you probably won't want to use 2,4-D. Which was our method of control. The organic route suggested was to spray the weed with vinegar, as strong as you can find (household is 5% you can get 20%) lay cardboard over top and cover with compost or rich soil 3-4" thick and mulch. Apparently horsetail thrives in poor soil and dies off in nutrient rich soil.

It is a major pain that I think one would want to try and control/eliminate if possible.

SCG

Thanks - I've also read that pulling is a big mistake! I'll try vinegar and also cut the greenery. I only noticed it in summer 2012, but it may take up to 5 years to get rid of it!!