Botanising on the Asphalt again

I've been taking Walter Benjamin's phrase literally on walks to and from the station lately, keeping my eyes to the ground and making a rough inventory of the plants breaking through and thriving - at least until the next visit from the weedkiller sprayers - in the gutters and on the edges of kerbs and pavements. It's not until you start counting that you realise how many species there are, happily living in these apparently inhospitable corners. I've identified three or four different grasses (don't ask me their names), various bittercresses and other crucifers, groundsel, sow thistle, chickweed and hawkweeds, willow herb, ivy-leaved toadflax, lesser bindweed, herb bennet, storksbills, green alkanet, mallow, lambstail plantain, redshank, spurge, the inevitable buddleia, and garden escapes including yellow fumitory (Corydalis), Oxalis and various poppies, including the 'Caiforrnia poppy', Escholzia. I'm sure there are many more that an expert botanist, working systematically, would identify - upward of 50 species perhaps, in 100 yards or so of pavement and gutter. All this abundance, all this persistence, the indestructible plant kingdom reminding us of the frailty of our tenure... As Horace would have it, 'Naturam expellas furca, tamen usque recurret' (you may drive out nature with a pitchfork but she hurries right back).
  But tomorrow I am heading for Dieppe to spend a few days as a summer flaneur, botanising the asphalt in the sense that Benjamin meant. Au revoir, amis...