I've read a lot of the material available about the debate over what came first the crack or the root, in sidewalks and driveways. I lean towards the crack being there first and thus creating an enviroment for the root to grow, it just seems to make more sense. Here is a little more proof for that side of the argument:
ps. Ananova is a great news site....http://www.ananova.com/news/story/sm_806004.html?menu=news.scienceanddiscovery
Ananova:
Scientists study pavement cracks
A group of German scientists has started a research project into the dirt that gathers in pavement cracks.
They say the matter deserves attention because the cracks are the only parts where the underlying ground and the air above it can exchange substances.
The research project is headed by Gerd Wessolek of the Technische Universitaet Berlin.
His team have already found that microbes living in crack dirt are three times more active than those living in natural ground.
They have proved to be effective in holding back harmful substances from car traffic.
A first analysis of Berlin streets and sidewalks also scientists some ideas on how the amount and quality of water let through by crack dirt affects the health of trees planted along the streets.
A spokesman for the project said it was set up to show that crack dirt is "a habitat that research has neglected up to now".
ps. Ananova is a great news site....http://www.ananova.com/news/story/sm_806004.html?menu=news.scienceanddiscovery
Ananova:
Scientists study pavement cracks
A group of German scientists has started a research project into the dirt that gathers in pavement cracks.
They say the matter deserves attention because the cracks are the only parts where the underlying ground and the air above it can exchange substances.
The research project is headed by Gerd Wessolek of the Technische Universitaet Berlin.
His team have already found that microbes living in crack dirt are three times more active than those living in natural ground.
They have proved to be effective in holding back harmful substances from car traffic.
A first analysis of Berlin streets and sidewalks also scientists some ideas on how the amount and quality of water let through by crack dirt affects the health of trees planted along the streets.
A spokesman for the project said it was set up to show that crack dirt is "a habitat that research has neglected up to now".
Sorry, I couldn't help myself.
