Friday, August 28, 2009

Invasive Species

Invasive Species in North and South America

Pestilence comes to mind first the scourge that hit the new world as we in our history phrase it. The Amerind population decimated by European diseases reduced almost wiped out in successive waves of disease originating at European contact points and spreading out way ahead of any physical meetings. Once the Amerinds caught the diseases, dying spread throughout the trade routes, making it easy for the Europeans to move in to a new territory. So European diseases were invasive species in North and South America, dating from at least 1492 onward. Mayan legend has it that death comes from the East, from across the ocean, which might indicate earlier contacts and bouts of disease originating in Africa.

These epidemics were followed by the introduction of European food plants and animals, hitchhikers like wharf rats, roaches and mosquitos, pets like cane toads, lionfish, English sparrows and starlings, working animals like donkeys and horses, food animals, the list goes on and on. Earlier introduction of invasive species through Chinese contact around 1420 and possibly earlier had brought Asian chickens and ducks, the Cherokee rose and a human intestinal parasite. Invasive grasses include Bermuda grass, pampas grass, fountain grass, rice, barley, wheat and rye, some food crops, some not. The mulberry, chinaberry, eucalyptus and tamarack all came in from Asia and the South Pacific.

Economic practices of humans included clear cut logging, burning, plowing, overgrazing, poisoning and dumping waste, all of which favored the new invasive species, much like the European diseases had prepared the way for European victory in the new world.

So now we worry about buffelgrass? The drought brings change in all species of the desert. The drought plus human destruction of habitat is devastating to the Sonoran Desert. Buffelgrass is used as fodder in Sonora and has been here at least 80 years.

The drought has changed the buffelgrass population. That which I observe appears to be damaged by the drought where continuing drying of the soil will kill it, seeing that the Sonoran Desert is on the edge of the possible range for this grass. So far this year I have seen little replication activity in the plants. These buffelgrass plants near I-10/Valencia are either dormant or dead as of 25 August 09.

The drought will do for free what all this controversy over spraying poison will do at a cost to taxpayers. I would like a cost rundown on this spraying project from all the cooperating entities, just to see how much money is being wasted on this poisoning. How many people could be funded to manually remove the grass, if it is that important to some people? Is spraying really what we want to do here? The Agent Orange personal devastation that many recruits suffered in the aftermath of Vietnam has never left my mind.

How soon some of you forget and accept the assurances of those selling the product.