Diana wrote: " If you tried to punch through asphalt with a shoot of a plant you couldn't do it, but plants frequently are able to do this amazing feat." Yes, they do, and if they are bulbous plants, doesn't that suggest another question? What I mean is, why, when the shoot is pushing up against the asphalt does the bulb itself not get pushed deeper into the ground? Does this mean that the force exerted by the roots which are supposed to pull bulbs downward is greater than the force it takes to pierce asphalt? It's becoming more and more improbable to me. Jim McKenney