Global warming warning! Be on the alert for the attack of the invasive weeds!
This is the latest in a long series of the possible consequences of supposed global warming. The dire scenario is set forth in a San Francisco Chronicle story by Joe Eaton and Ron Sullivan:
For educational purposes, the California Invasive Plants Council will sell you bouquets of plastic weeds, including yellow star thistle, tamarisk, leafy spurge and knapweed. Some recent studies suggest that many gardeners need not invest in these because they can expect more of the real thing to arrive as climate change advances.
Oh goody! I no longer need to shell out big bucks for those all-important plastic weeds. All I need do is wait for global warming to produce them naturally.
A warmer world will have more atmospheric carbon dioxide and nitrous oxide. UC Irvine's Diane Pataki says nitrous oxide has 300 times the global warming potential of carbon dioxide per molecule. It's released when soil bacteria covert ammonium to nitrite.
Aha! A new villain. Nitrous oxide. Remember all those hundreds of billions of dollars that were needed to combat carbon dioxide in the atmosphere? Never mind. We now need to blow our money on fighting the much more deadly nitrous oxide. Paging Al Gore!
Weeds from warm climates are poised to claim new turf as temperatures increase.
They are poised to claim new turf? Stop those poised weeds with a massive infusion of Cap & Trade funds!
Using each weed's preferred habitat characteristics and a scenario in which fossil fuel emissions are not reduced, Bradley and her colleagues created an invasion risk map for each weed.
May I have a weed invasion risk map to place on the wall next to my ManBearPig risk map?
Their results were mixed. The bad news for California: yellow star thistle will keep its current range and probably spread farther here and in Nevada. Tamarisk, an exotic tree that sucks wildland creeks dry, will neither gain nor lose in a warmer West. The largest effects the Princeton group predicted were for cheatgrass and leafy spurge, which will shift their ranges north, and spotted knapweed, which will move to higher elevations.
The bad news for California is that manufactured fear of cheatgrass and leafy spurge will suck taxpayers pockets dry.
Climate change is a moving target, and some effects could turn out to be stronger than the models account for. There's also no foolproof way to identify which plants will become invasives. But with weeds moving both in from wildlands and out into them, it's safe to say that weed control will still be on every thoughtful gardener's agenda.
Climate change certainly is a moving target since lately the climate has been moving in a colder direction. However, why are these writers even worried about this problem which has yet to happen? I mean they are in San Francisco. Wouldn't more weed available there be welcomed? And will global warming result in an epic battle between the invasive weeds and the killer tomatoes?