In every gardening forum I look at, I find that someone still believes that weedkillers like Roundup are inert in the soil/biodegradable/safe. Please do some research and don't believe advertising. Here's a tiny section from a recent review of the expose film, "The World According to Monsanto", and the facts cited here are widely reported elsewhere:
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Cancer is also implicated in Monsanto'ÂÂs showcase herbicide, Roundup. According Professor Robert Bell's research showing disrupted cell division, "Roundup provokes the first stages that lead to cancer." Bell, who is with the National Center for Scientific Research and the Pierre and Marie Curie Institute in France, says, "The tested doses were well below those which people normally use."
Monsanto has promoted Roundup as harmless to both humans and the environment. But their advertised environmental claims, such as "biodegradable," ÂÂ"leaves the soil clean", and "ÂÂrespects the environment", were declared false and illegal by judges in both the US and France. In fact, Monsanto'ÂÂs own studies showed that 28 days after application, only 2% of the product had broken down. They were forced to remove "biodegradable" from the label.
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No one has to resort to chemicals in clearing ground. We've inherited a large, neglected garden on heavy clay and have cleared it by hand. We are not super-fit and don't have much time, but it is surprisingly manageable. The key is to do a thorough job of removing roots the first time. Then, when things re-sprout, they are usually shallow-rooted and can be hoed off easily.