More settled science: Our CO2 emissions are simultaneously making the world's plants bigger *and* smaller

Global Warming Prompts Plant Size Decrease - - Softpedia

According to experts, it would appear that the average size of plants tends to decrease in recent years, when compared to the mean sizes they had in past decades. The researchers believe that this effect may be attributed to global warming.

2009: Plants buy Earth more time as CO2 makes them grow - Times Online

TREES and plants are growing bigger and faster in response to the billions of tons of carbon dioxide released into the atmosphere by humans, scientists have found.