This section is from the book "British Wild Flowers - In Their Natural Haunts Vol2-4", by A. R. Horwood. Also available from Amazon: A British Wild Flowers In Their Natural Haunts.
The flowers that follow man and the plough are perhaps no more artificial than those of the fields and meadows previously described, which have been equally disturbed by agricultural operations following the felling of forests, but there is a difference of degree, and a decidedly marked difference of origin as regards the unstable flora of a truly arable pasture, greater than that of one which is not actually under cultivation, unless we regard grazing as on a par with ploughing, which to be logical we ought to do. But with the former operation there is a marked physiological effect and a repeated reduction of all herbaceous growth to one level, while in the case of a cornfield we have free growth allowed till harvest, following seed ripening, and a temporary cessation of the struggle for existence caused by grazing. But, in the cornfield there is not that stationary association of species that a grass meadow possesses. It is largely ephemeral, the weeds (plants not classed as cultivated -as barley, wheat, oats, etc.) being of sporadic, alien or variable, colonist or denizen type, which may or may not persist perennially or annually.
Arable land generally is well drained and dry, and hence we may class it as pasture on cultivated soil, or under the plough. It is thus a part of the artificial though to some extent (because so stamped by time) natural mesophytic type of community, i.e. requiring a medium supply of moisture.
Really the cornfield flora is on a par with a waste land association (Vol. V, Section XI), which is here kept separate. But though there are many plants common to both, yet there are some peculiar to each; and because they have this distinctive character, though caused by the same abnormal factor, man, we keep them separate, as they are also topographically distinct. And this descriptive account of the common wild flowers blends the natural with the expedient; that is to say, the field botanist, whom we have especially in mind, finds here the most natural botanical mode of mapping the district, combined with the readiest mode of surveying it from a practical point of view.
Moreover, associated with the striking alien plants that come up with cereal and root crops are a good sprinkling of the pasture grasses, etc, which persist in spite of cultivation, especially on the borders of cornfields where the plough does not disturb the turf. Of these other plants, we have included here three at least, the prickly multi-coloured Hemp-nettle, which lurks in the hedge, White Campion, which grows frequently elsewhere, and several Fescue grasses, which are found also at higher levels on dry hills and the sides of walls, such as Sheep's Fescue.
Here between the blades of wheat we expect to find the Mouse-tail. Abundant and pernicious in the farmer's opinion, the neat Corn Buttercup fills many a wide interspace left where the grain has not matured. Towering halfway as high as the cornstalks in the East counties, Larkspur here and there is frequent, with its delicate blue blooms.
Poppies spread a blood-red mantle over the golden grain in almost every field of corn, and lurking low down cowers the foetid Earthsmoke with foliage like maidenhair. Everywhere the young blades of corn are outdone in the massing of colour by the Yellow Charlock, which, to the farmer's chagrin, studs the fields so plentifully in early spring. Sparingly the graceful woad-like Gold of Pleasure struggles upward, too, amid the ripening corn.
Purple and white, the lowly but pretty Candytuft in East Anglian cornfields brings a touch of the garden to the field. So too the little Heartsease, with its diminutive heads like dwarf pansies, recalls the rows of V, tricolor in the garden. The tall graceful White Campion opening to the honey-seeking insects at night is common here. Then no cornfield is complete without its Corn Cockles in the popular mind, but they are really more local than is usually supposed. The useful Spurrey spreads over the bare soil, affording fodder for cattle, but is little used in England. Common Flax reminds us of one of the sources of her greatness to-day, and once many a flax field could be seen in several districts, while now, as a rule, flax is imported.
On the stubble after the corn is cut, or amongst clover, Alsike Clover with its cream-and-pink orbs rises above the sandy soil laid bare at intervals. Shepherd's Needle with its comb-like seedcases, and its delicate little flowers and fine-cut foliage, is to be seen in most cornfields; and the foul and poisonous Fool's Parsley covers all the underglade with dark-green foliage; Field Madder and Lamb's Lettuce both cover the soil at the foot of the cornstalks where light pierces the rows of haulms. Bright-golden appear the flowers of the beauteous corn marigold amid the grain, varied with the rich blue flowerheads of the cornflower. Seeking the sun the scented Corn Sowthistle slowly twists its shocks of golden bloom in the wake of Hyperion. Hiding away itself and its bloom Venus' Looking-glass is rarely seen, though it is fairly common. Small Snapdragon, Ivy-leaved Speedwell, Scarlet Pimpernel, wakeful up till morning, the hard-fruited Corn Gromwell, the prickly but pretty field Bugloss, are all familiar weeds here amid the ancient Wild Oat and the death-dealing Darnel grass.