"All the idle weeds that grow In our sustaining corn." - King Lear.
Old Noah Webster defines a "weed" as "a useless and troublesome plant," i.e., a vegetable vagabond, not only idle, but mischievous. However worthless a plant may be from a utilitarian point of view, it is hence not a "weed " till it becomes so thoroughly at home in the land as to harass the gardener and the farmer; so it is merely a question of locality whether a plant is a weed or not. It may be quite without honor in its own country, where even beauty is no excuse for its being, yet under alien skies it may find itself the pet of the horticulturist. The little pink-tipped English daisy, so tenderly reared in New England gardens, is in its own country a troublesome lawn weed, while our homely mullein, that vagabond of the pastures, is - or used to be - cherished in Irish greenhouses under the name of "American flannel-plant." I have even heard that there are places west of the Mississippi where wild-carrot, despised intruder on Eastern lawns, is cosseted and extolled under the appropriate alias of "lace-flower." It is a pity that we, in the Eastern States, have become blind to the beauty of its feathery leaves and its wheels of delicate bloom, which in later August fill every field and roadside with unloved loveliness.
Fig. 97. - Amaranth and sow-thistle (Amarantus retroflexus and Sonchus asper).
Indeed, all weeds are much in evidence in late summer and autumn. The flowers of most sorts are inconspicuous, but the seeds which follow compel attention by sheer force of numbers and ubiquity. They are here to-day to fight the farmers because they practised, ages ago, what the farmers have learned only within much more recent times.
Nature has taken extraordinary care that the seeds do not drop at the roots of the parent-plant into an exhausted soil. The weeds sow themselves broadcast each autumn. Some are provided with feathery plumes, and thus made so buoyant that the lightest breeze will bear them fast and far. Every autumn gust is freighted with a mixed company of these little flyaways. Thistle, sow-thistle, dandelion, milkweed, and golden-rod seeds all fly on feathery wings, and thus the respective families are kept up, and are spread over the country.
Some weeds lay hold on the passer-by, quadruped or biped, and force him, will he, nill he, to sow their seeds abroad. To bring this result about, the seed or fruits are barbed, and they claw the unwary traveller and cling to him with exasperating constancy. When the "stickers" are at last picked or rubbed off, they fall to the ground, probably many rods from the spot where they grew, and thus Nature's purpose with regard to them is achieved. This is the way the ragweed travels. The thorny seed-vessels of the cockle-bur and the burdock also obtain free transportation in return for their close attachment to some wayfarer, quadruped or biped. So successful have been these schemes that the weeds which put them into practice have travelled half around the globe. Like an invading army they push further and further on, despite all the resistance of the owners of the soil.
Many, indeed most, of the dooryard weeds come from the Old World, and have already travelled across this continent to the newly-cultivated lands of the far West. Some varieties seem unable to live far from human habitations, and persistently follow us up in the teeth of all opposition. Like the mediaeval Highlanders they have become sturdy and resourceful in the stern training-school of continuous war. We can almost say that the worse nuisance a weed is from the agricultural standpoint, the more highly is it adapted to the conditions of its life, the more is it a triumph of reproductive Nature.
It is common just because it has been able to travel, to endure, to survive, to live down and crowd out a host of things, prettier perhaps, but less able to battle for existence.
Some weeds have timed themselves with wonderful accuracy to the operations of the farmer. That bugbear of English wheat-growers, the scarlet-poppy, has acquired the habit of ripening its seed-vessels at the precise time when the wheat is ready for the sickle.
In our land and latitude, after wheat is reaped, the fields are taken possession of by weeds which regulate their affairs with such nicety that they grow, blow, mature their seed-vessels, and scatter their seed, all between the ingathering of the harvest and the coming of the frost, "They blow," we say, for all weeds bear flowers. Most sorts belong to that immense and successful botanical family, the Compositae, which produce a very great number of very minute flowers, often so grouped as to resemble single larger flowers. To the unbotanical public the most familiar is the daisy. Its yellow centre or disk is an assemblage of little trumpet-shaped blossoms, set as close together as possible. In a ring around this disk we see what botanists call the "ray-flowers," and what non-botanists call the "white leaves" of the daisy. On close examination these will be found to be tiny florets with a pistil apiece, but with no stamens, and with their white corollas split open all down one side. So the daisy, which looks like one flower, is really a close mass of very tiny blossoms. The cockle-bur, ragweed, sneezeweed, burdock, and sow-thistle are all Compositae. So are the groundsel and the bur-marigold. So is that enemy to the western farmer and darling of the patriotic Scot, the thistle.
Each of the minute flower-clusters which are massed together in a tuft of golden-rod is made up after the daisy pattern, and proves, on examination, to be a head of disk-flowers surrounded by an aureole of ray-flowers. Asters are clearly seen to be arranged on the daisy plan. So is the brown and yellow "cone-flower" or "black-eyed Susan," and so are the sun-shaped things with names beginning with "heli" which run riot over the August landscape, as if earth had grown enamored of the sun and copied his dear image, again and again in her flowers.