Pulling down to correct level

Jim McKenney jimmckenney@starpower.net
Wed, 13 Jul 2005 15:40:09 PDT
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

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