It may work, but @$17 per quart, it's vinegar with cooking oil that you could make yourself . "For best results, spray in full sun in the afternoon", same as you would using household vinegar, no oil.

The real trick with your shotweed is to not let it go to seed. Weed it out, mulch to cover any existing seeds that may be present - they won't germinate.

I've used a different non-toxic product, called Weed-aside. The name sounds like it was from Gardens Alive, although I'm not sure where I picked it up. The active ingredient is ammoniated soap of fatty acids, 22%. Claims to kill weeds, algae and moss, which makes it a little dicey for me since I GROW moss.

I tried it on ladybells, Adenophora, which is a pest in my area. It is about as effective as cutting off the tops of the plants - maybe a little less so. It made them wilt, and that's about all it did.

Cardamine hirsuta is an annual, and should be susceptible to any pre-emergent weed "preventer" including corn gluten meal. But maybe that also makes it a good candidate for the non-toxic herbicides that just kill the plant tops; no top, no seeds; I guess whatever you can do to interrupt the life cycle and prevent seed production would work.

It's also possible that the vinegar in phydura might acidify the soil enough to cause problems for other plants growing nearby - depending on how much you need to use.

Here is a link that might be useful: Pydura

morz8,
Thanks for your response I agree with your suggestion of not allowing the hairy Bittercress go to seed but unfortunately for me I have now learned that the hard way. After turning my back on this pest just two short years ago it has now taken over my lawn (that I would have considered a healthy), gardens, shrub borders, woodland, brick path/patio, and to be honest I am half expecting to wake up one morning to find it growing on my pillow case. It wintered over nicely in my zone and I treated my lawn with corn gluten before its first seeding of the year. I am considering this product for areas too large for hand weeding which to be honest this is not a difficult weed to pull. kt

dtd,
Thanks for the great info, there is nothing like first hand experience passed on to other gardeners. I think I am going to give it a try by spot testing under different conditions. I'll report back my success/failures at a later date. kt

It should be remembered that the products mentioned above are not non-toxic. Note the Phydura label: "Keep out of reach of children" and "Causes eye irritation. Wear safety glasses and gloves when applying."; and the Weed-aside label carries a "Warning" label- both of these reflect toxicity precautions higher than some synthetic herbicides. All natural does not equal non-toxic.

What is going to "kill" the plants is the Vinegar, and the oil is there to help the Vinegar stick to the plant leaf. The clove oil is there most likely to make the product smell pleasant. This does nothing more than what the much less expensive Vinegar would not do.

Hmmm...Now I am really confused. As my drinking water comes from a well I am not taking this lightly. I suppose I should ask would any of you apply this product on your own property? kt

This product should not create a problem for your well water, or for you or your family as long as it is applied correctly.

And actually, clove oil is used in various natural based herbicides for its herbicidal properties. In this product it appears to be at 12% concentration, and is the stated active weeed control ingredient, along with sodium lauryl sulfate. The vinegar component is not listed as an active ingredient, but of course this is not the reality. Other plant essential oils are also used in similar products, such as rosemary oil. In high enough concentrations they can affect top growth of weeds. One interesting thing that is not commonly known is that the clove oil component (eugenol) is a well known carcinogen, although a natural one.

I would not use this particular product, not for safety reasons but for price reasons.

I think the main idea to keep in mind is "know thy enemy" - and in this case it means, to me, don't bother killing the plants, because they have such a short life span. Herbicides make many annuals immediately set seed; it's what they're genetically programmed to do to keep their species going.

I was pulling hairy bittercress seedlings all winter in a sunny, protected spot in my yard. They were literally flowering in the snow (what little snow we had this year).

CGM doesn't have much residual effect, which in this case is too bad, since these buggers' seeds seem to sprout continuously. I don't know about the toxicity of longer lasting pre-emergents, but that's what you need, something that will keep seeds from sprouting or keep sprouted seeds from developing.

So far I've seen only a few of these in my lawn, mostly they are in areas where there's bare soil or mulch. They sure are cute and they sure are pests.

I usually dig and pull the grass out . But have rock walls on raised hillside beds and the grass grows between the rocks.
Might the vinegar work? I was getting so frustrated I was considering Roundup...but this discussion convinced me to remain as close to organic as possible. I will be planting members of the squash family in the bed above the rocks and will have to be careful spraying one the plants are in.

The list of components of Phydura from it's MSDS is as follows: Clove Oil, citric acid, malic acid, potassium oleate, lactose, water. I can see how the synergy of these components should make a short life for any plant you spray it on provided it's not too dilute.

Here is a link that might be useful: Phydura datasheet

As some of us learned back in the 1960s and 1970s very often when two rather innocuous chemicals mix they can produced a very toxic substance, and we are still paying a lot of money cleaning up behind chemical companies that made some people very rich and then went banktrupt so the owners would not have to pay for the cleanup that is still going on. While non of the products that make up this, or any other, "weed" killer by themselves may be toxic mixed together may be something else. The EPA does not require anyone mixing GRAS products to test them in combination to see if they are safe, operating under the worng assumption that GRAS products will remain so.