---- "David L. McNeely" <[email protected]> wrote: > ---- Jason Hernandez <[email protected]> wrote: > > The problem is that "people" (meaning laypersons from the point of view of > > the particular scientific discipline) do not actually read *scientific* > > literature on it. How often have we seen -- in books about horticulture, > > landscape architecture, and so on -- that willows should not be planted > > near underground pipess because their roots will enter and thus destroy > > said pipes? To someone unfamiliar with the science behind it, it would > > *appear* to be saying that the willows somehow detect the presence of water > > in the pipes and grow into them seeking said water. Such literature does > > not make explicit what we know: that this phenomenon presupposes that the > > pipes are already leaking, the willow roots are already in contact with the > > resulting gradient, and grow along the gradient into the existing leaks in > > the pipes. Add to this the phobia of most non-scientists toward reading > > scientific literature -- because they already assume they will not > > understand > > it -- and there is little to counter such misconceptions arising from > > oversimplification.
Another important point that the lay person can certainly understand: the roots do not grow into water service pipes under normal circumstances. How many times has anyone had to call a plumber to "roto-root" the water service pipes? Never. Only the sewer pipes, by the nature of their construction, leak at the joints, and roots enter them due to the water gradient established. Not the water service pipes, which have sealed joints where joints occur. Sewer pipes are typically "layed in," without sealing, and may be "orangeburg" (tarred paper), clay, or cast iron. More recently they are pvc, and those may (but not necessarily) be sealed at the joints. Point that out to the person who believes that the roots have sought out the water. It might help their understanding. mcneely
