Itchier poison may increase with Global Warming

Here is another reason to worry about global warming: more and itchier poison ivy.

The noxious vine grows faster and bigger as carbon dioxide levels in the atmosphere rise, researchers reported on Monday.

Higher carbon dioxide levels expected in the next 50 years could breed ivies that grow twice as fast, and, unexpectedly, manufacture a nastier form of poison, research in the United States have shown.

"It'll be more dangerous to go in the forest," team leader Jacqueline Mohan of the Marine Biological Laboratory at Woods Hole, Massachusetts was quoted by Nature magazine as saying.

Poison ivy (Toxicodendron radicans), which grows as a shrub or tree-climbing vine, is already the scourge of gardeners and hikers in North America for the excruciating skin rash it can trigger. The plant makes a fatty toxin called urushiol in its leaves.

Unlike trees, which use extra carbon to grow more wood, vines use it to produce more leaves. The extra leaves help the plant to harvest even more carbon dioxide, the cycle continues and the vines flourish.