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Re: [RC] weed free - Sisu West Ranch"....Yes, but who decided this was WRONG? Who decided what is NATIVE? ...."We do not have the luxury of waiting for 10,000 years for an ecosystem to adapt, if it ever does. Some plants are a annoying some really do destroy. Example: In the rather arid Bitterroot Valley spotted knap weed (that came in from Asia, but without the insects that control it there), will take over an area. It secretes a chemical that kills other plants. The result is that grasses that hold the soil from erosion do not grow. Only goats and sheep will eat it. Horses, cows, buffalo, elk, etc. do not. Finally there are some insects being imported that will help control it's spread. (by the way the importation of insect pests is a danger in and of itself and not to be done lightly.) The problem with evolution is two fold. One it is very slow. Often we can't wait the 10 or 100 thousand years. Also it must work with the genetic base it has. There is no guarantee that if a plant comes in, and pushes out the other plants that even after 100 thousand years it will not be the dominant plant in the area. If this plant is poisons or non nutritious, the area will not ever be able to support grazing animals. If it can't support them, there will be no predators (including people) who need to eat the grazing animals. One could claim that if there is a poisonous plant (like the potato leaf), and there is an insect that has evolved to eat it (like the Colorado potato beetle), that this is proof that a new insect will evolve to eat and thus control a noxious weed. Unfortunately, this most likely will not happen. In the dim dark past an ancestor to the potato happened to produce a little bit of a slightly poisonous compound. Most insects and animals avoided it to a certain extent and thus it persisted. At the same time, some of the insects that were to become the potato beetle, could tolerate a small amount of the chemical. Over many generations, the potato produced more and more toxic chemicals, and the beetles became more tolerant of the chemicals etc. Unfortunately, the amount of toxic material in the leaves of a potato now far exceeds the tolerance of every modern insect except the potato beetle. There will most likely never, even in a million years, be an insect that will evolve to eat potato leaves. (Actually, I believe that the potato beetle evolved eating another member of the nightshade family, and thus opportunistically started eating potatoes when people started planting them in the area. This is still an illustrative oversimplified example of the limitations of evolution) ED Ed & Wendy Hauser 2994 Mittower Road Victor, MT 59875 (406) 642-9640 ranch(at)sisuwest(dot)us =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-= Ridecamp is a service of Endurance Net, http://www.endurance.net. Information, Policy, Disclaimer: http://www.endurance.net/Ridecamp Subscribe/Unsubscribe http://www.endurance.net/ridecamp/logon.asp Ride Long and Ride Safe!! =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
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