Will Roundup disipate in soil in time?

Question

I had a strip of lawn that was all weeds. I sprayed it with Round-up. I plan to rototill the strip after the weeds die, rake out the dead weeds, then plant new grass in the area. If I put too much Round-up, will that eventually disipate in the soil, or is it there for good?

Answer 1

RoundUp was / is touted as being safe to use, that there is no harmful residue left in the soil. However, they said that about DDT when it was introduced as well, so only time will tell.

In the meantime, and to answer your question - I think you are asking if it will persist in the soil and harm the lawn you want to plant there - no - it only works on the active growth area of a plant when it is applied directly to that green growth.
It was not persist in the soil and thus harm your new lawn. So go ahead and plant it.

Answer 2

Roundup was designed to do just what you want--use it and have it breakdown in 1-2 weeks. They wanted something you could spray a weed patch with and then in a week or two plant flowers. So you could go from a weed bed to a flower bed in a short period of time.

Ironically it was this feature that many people did not like. They would spray the cracks in their driveway to kill the weeds and it worked but a month later the weeds were back. And they said Roundup stinks--it doesn't work. Well, it works like it was designed to work.

If you overdid it it may take a little longer than 1-2 weeks but you will definitely be able to reseed you lawn successfully, UNLESS the Roundup you used was their new version "lasts 4 months" product. If it was regular Roundup you're OK, especially if you're going to rototill. One other note: when you rototill you inevitably bring buried seed to the surface where they can germinate so your first year you may have a lot of weeds and wonder where they came from.

Answer 3

RoundUp has very short residual... you can typically plant things few days after spraying RoudUp. It also has very low environmental impact because it has NO soil residual.

http://www.pestproducts.com/roundup_dry.htm

You can aso get this information on the Monsanto website (manufacturers of RoundUp) and check out the label ad MSDS sheet. There are different kinds of roundup, so make sure you look at the label for the product you used. Some agricultural crops cannot be planted for up to 35 days if they were sprayed with RoundUp, that is why you should look up the product you have.

Many of the pesticides that have long residual (stay in the soil for long periods, like DDT) are no longer available in the U.S. The EPA regulates all of this!

Answer 4

There is a chart available for when certain things can be planted after the use of roundup. Many shrubs and ornamental are 1 day, vegetables and transplants - 3days and some plants you have to wait a month. The active ingredient is broken down by microbes in the soil over time. Plants do not absorb the active ingredient throught the roots, only the leaves.

Answer 5

Yes, round-up will loose it's toxicity in about three weeks. If you water the area heavily, or experience a great deal of rain, the product will probably dilute even more quickly.

Often you will need to apply a second round of round-up to catch any stragglers, or spots that weren't sprayed heavily enough. Be sure to allow for that extra time.

Good luck -

Answer 6

All weed killers are soluble in water, so they will be washed away with rain in time, maybe 3 to 5 weeks.
I suggest you consider using Bayer Advanced lawn weed killer. It kills weeds and really does not harm the grass. If there is any grass left, it will come back. It may save you some work.

Answer 7

the life of substances are measured by their half-lives (the amount of time it takes for 1/2 of the substance to expire). some substances take longer to expire than others. I think certain chemicals in the solution will remain while others hang around for longer than your lifetime. also, the concentration will dissipate as it rains and water washes it all around the area.
if you are worried about chemicals staying there. you will need something to consume it or use itup. I would use an innoculant/probiotic of soil-based organisms/bacteria, such as SCD EM, to begin eating the compounds. the remaining Round-up It will kill some of them off as Round-up is a poison to living things, but eventually it will break down as the microbes consume what compounds they can.
thats probably too much information.

Answer 8

It can dissipate into the soil,but it will so weak,it will not have any environmental effects.The inert ingredients,in the home owner version of Round Up,are only @ 5%,unless you bought the super concentrate (49%).

Answer 9

Regular Round-Up, applied as directed on the label should last for two-three weeks. Then you can plant over the area. If your using Season Long RU, it will need to remain untouched for three months. Good louck!

Answer 10

If you are interested in saving a bit of money, you can make your own "Weed Killers". See Site for 7 Recipes, guaranteed to help you eradicate all weeds, which I have used for years.
http://www.thisgardenisillegal.com/2006/05/7-deadly-homemade-weed-killers.html