So, what’s new on the patch of re-vegetating quarry spoil I’m watching this month? At first glance, not much – the area in the background here, which was covered with new topsoil around this time last year, now looks to be covered in fairly dense grass, in contrast with the sparser vegetation on the older spoil.
However, things are often not quite what they seem! There are big patches of thistles, amongst the grass – mainly sprawling Creeping thistle but also some Spear and Welted thistles with attendant pollinators.
Last month’s diminutive Field pansies have nearly all finished flowering but amongst the grass there are also three tiny new plants which I haven’t seen here before; Fat-hen, Knotgrass and Black bindweed. All three are inconspicuous but common arable and waste ground species, though not ones I particularly associate with the limestone grassland of this area. Fat-hen is a Goosefoot, named for the shape of its leaves, though its common name is a better indicator of the fact that the seeds are a useful food source for birds and were a supplementary food for early human farmers. The other two are members of the dock family some of which, such as buckwheat, also produce nutritious seeds.
I don’t really find any new species on the older spoil and, in fact, many of the plants which were flowering a month or so ago are now in seed. What is interesting is that this month, for the first time, I find very similar numbers of species in flower in the two habitats – 19 on the disturbed ground where topsoil was added in comparison to 21 on the older spoil. The species are different, but the numbers seem to be evidence of a similar level of latent diversity in the topsoil seed bank.
Here is the August list for the two habitats.
|Disturbed ground||‘Original’ vegetation on older spoil|
|Creeping buttercup||Ranunculus repens||p|
|Slender St John’s-wort||Hypericum pulchrum||p|
|Field pansy||Viola arvensis||p|
|Dame’s violet||Hesperis matronalis||p|
|Scarlet pimpernel||Anagallis arvensis||p|
|Creeping cinquefoil||Potentilla reptans||p|
|Blackberry||Rubus fruticosus agg.||p|
|Red clover||Trifolium pratense||p|
|Tufted vetch||Vicia cracca||p|
|Rosebay willowherb||Chamerion angustifolium||p||p|
|American willowherb||Epilobium ciliatum||p|
|Fairy flax||Linum catharticum||p|
|Cut-leaved Crane’s-bill||Geranium dissectum||p|
|Wild carrot||Daucus carota ssp. carota||p|
|Upright hedge-parsley||Torilis japonica||p|
|Welted thistle||Carduus crispus||p|
|Common knapweed||Centaurea nigra||p|
|Greater knapweed||Centaurea scabiosa||p|
|Creeping thistle||Cirsium arvense||
|Spear thistle||Cirsium vulgare||p|
|Rough hawkbit||Leontodon hispidus||p|
|Oxeye daisy||Leucanthemum vulgare||p|
|Common ragwort||Jacobaea vulgaris||p||p|
|Mouse-ear hawkweed||Pilosella officinarum||
|Prickly sow-thistle||Sonchus asper||p||p|
|Crested dogstail||Cynosurus cristatus||p|
|Annual meadow grass||Poa annua||p|