Scientists want to perform an experiment to see if poison ivy grows taller when exposed to more carbon dioxide. how should the control group in this experiment be treated?

The carbon dioxide is one of the green house gases and mainly responsible for the increase of the earth's temperature. The plants uses the carbon dioxide for the photosynthesis process.

The plants that are exposed to the normal carbon dioxide can be used as a control in this experiment. Then the scientists will notice that if the amount of carbon dioxide is increased, does it show any positive or negative effects in the experiment.

explanation:

for  example, forests have higher evapotranspiration than other ecosystems,  such  as grasslands, because of their deeper roots and greater leaf area. thus forests have a net moistening effect on the atmosphere and become a moisture source for downwind ecosystems.