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Roundup Ingredient Lands On State's Dangerous Chemical List

Associated Press
Containers of Roundup, left, a weed killer is seen on a shelf with other products for sale at a hardware store in Los Angeles on Jan. 26, 2017.
Roundup Ingredient Lands On State's Dangerous Chemical List
Roundup Ingredient Lands On State's Dangerous Chemical List GUEST: Nan Sterman, host, "A Growing Passion"

Going out to the garden to do some weeding got more complicated in California. Starting Friday state regulators will list the active ingredient in roundup as a potentially cancerous chemical. They say they will join more than 900 substances identified as dangerous consumers on the states propped -- prop 65 list. Since it is a widely used weed killer the new warning may have lots of people searching for alternatives to keep their gardens weed free. Here was some advice is Nan Sterman host of the KPBS TV show a growing passion. Welcome to the program. Thank you. What is your first go to method of getting rid of weeds? It is betting -- bending over and pulling them out. There's something that can assure they will not go back. There is two different category of weeds. There is a group of weeds that have very find threadlike roots so it doesn't matter what they look like it is belowground and their roots are really fine and threadlike. Then there are plants that have roots that are very thick and fleshy and often deep and that's what you find underground. Weeding those two kinds of weeds is different. When it comes to the weeds that have the narrow threadlike roots as long as you can remove the leaves on top of the ground, those plans are going to die right away because there is nothing to feed the roots, but when you're dealing with those that have the sick roots that are deep or even horizontal but thick and fleshy, removing the leaves is not the complete solution because those fake roots store energy and it will re-sprout leaves. There's a lot more to it than that. I hear you personally find helping rather satisfying. Honestly I find weeding satisfying. The first thing to say is that people are afraid or hesitant for some reason to pull their weeds and get down on their hands and knees and just pull them out. That is the most effective thing to do because you want to get rid of the roots. If you have a space where there's lots of weeds and it's more than you can do by getting on your hands and knees, then you get a [ NULL ] and scrape away the leaves. The mechanical approach is the preferred approach and the first thing you do. Your big recommendation is mulch with -- which adds nutrients to soil but wouldn't that make the soil more attractive for weeds question mark Balz does not add a lot of nutrients but it also helps to improve the soil quality. The reason that I recommend mulch is you are trying to smother the weeds whether there already standing tall or smothering the seeds in the soil that could sprout and become weeds. That is part of what mulch does. That is a whole idea of mulching over weeds. If your weeds are short, that is easy to do just add on a thick layer. Some people who are concerned about the possible cancer warning on Roundup may want to just switch to another product that they can spray. So are there actually organic alternatives to a product like Roundup? That is complicated. Yes and no. There are products that are advertised as being organic weed control. Often they are made of things like cinnamon oil or made from an extract of citrus wind and what it does is it breaks down the waxy layer on the surface of the leaves so they defecate even though you can't see it almost every plant has a thin layer of rocks in the surface. Now the thing is with those kinds of products they don't work in everybody's hands. They work for some people but don't work for others. They will kill whatever hassles find threadlike roots. If you're dealing with Bermuda or something with a thick fleshy route, it's going to be sprout. Should they protect themselves even when they are using organic weed killers. Absolutely. You always want to read the label and use protections. It doesn't matter what the product is you always have to do that. Another thing that people ask about is using vinegar. Vinegar is very weak. It will kill some things but not much. It is 10 to 20%. It's approved as an organic weed killer and you can use it but it will kill those plans that have the find threadlike roots but not the one -- ones that have the thick roots. You and then lay down a thick layer of mulch and then you pick out whatever -- from bird droppings or off your dogs coat or shoes. Nothing stops weeds from landing or blowing in after you've weeded. All you are doing is what you are doing is getting rid of the weeds that are there. It's like dishes and laundry. You will never stop doing them. I've been speaking with Nan Sterman . Thank you. Thank you.

California regulators on Friday will add the active ingredient in the weed-killer Roundup to a list of chemicals that may cause cancer, meaning Roundup and other herbicides with the chemical will have to display warning labels by next year.

Roundup maker Monsanto said the chemical, glyphosate, is not carcinogenic. The company is suing the state to remove the listing under Proposition 65. There are currently more than 900 substances on the state's potentially-dangerous chemicals list.


Since Roundup is the most widely-used weed-killer in California, the new warning may have lots of people searching for alternatives to keep their gardens weed-free. Garden expert and "A Growing Passion" host Nan Sterman said the simplest technique is often the most effective: just pull them out by hand or with a hoe.

"Personally, I find that really satisfying," Sterman said. "I use an asparagus knife and I just stick it in and pop the root out."

Sterman also recommended laying down at least three inches of mulch to help smother any burgeoning weeds. Another benefit is that if new weed seeds land on top of the mulch, it is a lot easier to pull weeds out of mulch than dense dirt.

Sterman joins KPBS Midday Edition on Thursday with more weeding tips, including organic sprays that could replace Roundup as a go-to tool.