Posted: 17/11/2013 at 19:50
As nutcutlet says - spraying glyphosate onto open ground is a waste of money. Glyphosate is a translocated weedkiller. It requires contact with growing/live tissue. Leaves on pants absorb it and it spreads via the plant's vascular system. For e.g. tree stumps you are looking at painting a strong solution onto freshly felled/cut stumps ('freshly as in no longer than about 30 minues) or drilling through the bark into the cambium and carefully injecting it. Spraying it willy-nilly onto bare soil won't help your pocket or anything else.
Talking of weeds, this summer wasn't 'kind' to me in trying to get on top of some of the perennial weeds in the inherited garden. The summer was dry and it affected weed growth (which was delayed by the late spring anyway). At least I had opportunity to hoe off a lot of weed seedlings. I'm tackling celendine, field bindweed, nettle, willow-herb and bramble as well as dandelion, field and creeping buttercup, couch grass plus a variety of annual weeds (and an outbreak of honey fungus). I look on such things as a multi-year 'project'. The past neglect of the garden requires a similar amount of time to put it back into shape. Some of the above mentioned 'weeds' will be welcome in parts of the garden when it comes into shape.
Weeds are a part of gardening. There are times when I've thought of self-sown buddlieas and lady's mantle (alchemilla mollis) as weeds. The latter (garden plant) breeds/seeds prodigiously and isn't fussy at all when it comes to soil types. I'm just thankful I'm not having to battle with Japanese knotweed, ground elder, horsetail and himalayan balsam.
With regard to celendine (that is what is shown in your shots), I recently (1st week of November) cleared a small bed. I knew there were celendine in it (saw them in the spring). The 'pips' were starting to shoot (as were the mish-mash of daff bulbs and crocus corms). I think I managed to get the majority of the celendine pips removed. I may have to give attention to any that remain. I'll also point out that there are named 'types' of celendine that have purple leaves. If they pollinate/seed they are prone to reversion to the original species type. Been there, done that. They seemed like a good idea at the time...
For the plants growing in the cracks I would revert to manual methods. Old knife, patio knife. Persistently destroying the top growth will exhaust the tuberous roots. Another alternative is to lay a weed membrane. That will exclude light and likewise cause the demise of the unwanted plants. It will need pegging down so that the wind doesn't blow it away. At a guess, for celendine it will take a year (maybe two?) and won't look nice in the meantime. After that you would have to keep an eye out for germinating celendine seedlings (seed can remain viable for many years). I remember a rhyme - "one year's seed, ten years weed". (or something like that).