I've been making notes about the local flora. Should this be of mild
interest, these are the 20 most widespread (not necessarily the
commonest) species - the figures in brackets are the number of "sites"
in which they are present, where a site averages about a square
kilometre. No grasses, as I can't tell them apart. There are also biases
against late-flowering plants, and arable weeds, so take the figures
with a pinch of salt.

1. Nettle - Urtica dioica (93)
2. Cleavers - Galium aparine (89)
3. Creeping Buttercup - Ranunculus repens (75)
4. Elder - Sambucus nigra (75)
5. Dandelion - Taraxacum officinale agg (73)
6. Hogweed - Heracleum sphondylium (72)
7. White Clover - Trifolium repens (71)
8. Broad-leaved Dock - Rumex obtusifolius (65)
9. Cow Parsley - Anthriscus sylvestris (63)
10. Daisy - Bellis perennis (63)
11. Bramble - Rubus fruticosus agg. (62)
12. Sycamore - Acer pseudoplatanus (61)
13. Common Ragwort - Senecio jacobaea (60)
14. Creeping Thistle - Cirsium arvense (59)
15. Ribwort (Plantain) - Plantago lanceolata (59)
16. Garlic Mustard - Alliaria petiolata (57)
17. Foxglove - Digitalis purpurea (57)
18. Ash - Fraxinus excelsior (57)
19. Spear Thistle - Cirsium vulgare (56)
20. Rosebay Willow-herb - Chamaerion angustifolium (55)

--
Stewart Robert Hinsley