Show Details

Shrubs and CO2

September 25, 2007

Carbon dioxide emissions can help shrub weeds at the expense of grasslands.


How greenhouse gases can change landscapes. I’m Bob Hirshon and this is Science Update.

For over a century, shrub weeds have been crowding out grasslands. It’s been suspected that greenhouse gas emissions are partly to blame. Scientists in Colorado grew grassland plants in two domes: one with today’s atmosphere, and one with carbon dioxide levels doubled, as expected by the end of this century. According to plant physiologist Jack Morgan of the USDA’s Agricultural Research Service, in the high-CO2 condition, a woody shrub called fringe sage grew forty times as much.

JACK MORGAN (USDA Agricultural Research Service):
What this experiment does is it supports the notion that woody plants in general respond to CO2.

If further studies confirm it, it could mean that livestock and wild animals may have to adapt to shrinking grazing areas in the future. I’m Bob Hirshon, for AAAS, the science society.