Another member writes he has some areas where couch grass (Agropyrum repens) is invading and that he will have to redo the paving! For what this is worth, I have a patch of creeping thyme [= serpolet??] that flowers beautifully and that I am extending throughout my lawn. I have observed that very few weeds grow in it, and those that do are very shallow rooted. I am now also considering it for the interstices between the flat stones in my footpaths. Anyway, they are steppable on. J. Denys Bourque Saint-Jacques, NB CANADA