High CO2 reduces roundup effectiveness http://goo.gl/652N

I encourage everyone to download and read the climate change report put out by the US Global Change Research Consortium.

http://goo.gl/652N

Here is an excerpt:

"Controlling weeds currently costs the United States

more than $11 billion a year, with the majority

spent on herbicides;241 so both herbicide use and

costs are likely to increase as temperatures and

carbon dioxide levels rise. At the same time, the

most widely used herbicide in the United States,

glyphosate (RoundUp®), loses its efficacy on weeds

grown at carbon dioxide levels that are projected

to occur in the coming decades (see photos below).

Higher concentrations of the chemical and more

frequent spraying thus will be needed, increasing

economic and environmental costs associated with

chemical use."