We are all familiar with the oft-quoted lines: "Tender-handed stroke a nettle and it stings you for your pains," etc. They were written by Aaron Hill on a window in Scotland. Their thought is more tersely expressed in the old Devonshire saying: "He that handles a nettle tenderly is soonest stung," meaning that politeness is wasted on some people. For the physical sting of the vegetable nettle the dock-leaf is a remedy, whence the old adage, "Nettle out, dock in, dock remove the nettle sting." In old-folk medicine nettle-tea was a remedy for nettle-rash, a kind of foreshadowing of the coming doctrine that "similia similibus curan-tur." Carried about on the person, the nettle was supposed to drive away fear, and on this account it was frequently worn in time of danger. "In the Tyrol, during a thunder-storm," says Thistle-ton Dyer, "the mountaineers throw nettles on the fire to protect themselves from lightning, and the same safeguard is practised in Italy." Well might this be a potent weed, for it is own cousin to the famous and fatal upas tree of Eastern story.
The thistle, companion of the nettle in vagabondage and in public execration (Fig. 94), is likewise deserving of a better fate and of a higher place in popular estimation. For it has been renowned in legend and wonder-lore, and has moreover played no mean part in authentic history.
The old world knew it as a potent herb in charm-working and in folk-medicine. It was famed in the heraldry of the Middle Ages. And modern science recognizes it as one of the most highly organized of wild flowers, wondrously fitted to fight its own battles and to make friends for itself in the insect world.
Long, long ago the thistle was sacred to Thor, the Norse god of war and thunder. It must be gathered in silence, and its blossom was supposed to be colored by the lightning from which it defended. In English folk-medicine the weed continues to play a creditable part.
The blessed thistle is so called because it was an antidote to venom. The melancholy thistle, a recently arrived immigrant from the Old World, was a sure cure for that vague but distressful malady, "the blues." In rural England the thistle was - perhaps it still is - used in love divination. "When anxious to ascertain who loved her most," says Thistleton Dyer, "a young woman would take three or four heads of thistles, cut off their points, and assign to each thistle the name of an admirer, laying them under her pillow. On the following morning the thistle which has put forth a fresh sprout will denote the man who loves her most.
Fig. 94. - Common thistle (Cnicus lanceolatus).
As the geese once saved Rome, so the thistle saved Great Britain, by causing a midnight alarm and scaring off a midnight foe. A thousand years ago the inhabitants of England and Scotland were much harassed by the Danes, who sailed far up the rivers in flat-bottomed boats, attacked the villages, destroyed the crops, seized the movables, drove off the cattle, and were back in their boats and away before the astonished British could collect their thoughts and their forces, and punish the marauders as they deserved. But sea-robbers as the Danes were, they had a code of honor which forbade them to attack a sleeping foe. On one occasion, however, they were false to this tradition, and landed on the shores of a Scottish river in moonlight and silence, intending to surprise a sleeping village. But as they crept stealthily upon this evil errand one of them trod, with naked foot, upon a thistle. He very naturally cried out, and his clamor wakened the villagers, who flew to arms, and drove the sea-robbers away. Thereafter the thistle was honored in Scotland as the goose was in Rome. It was adopted as the national flower. It blooms with the rose of England and the shamrock of Ireland in the floral emblem of Great Britain, and many noble Scottish families have portrayed this wayside weed on their escutcheons.
The thistle is a member of the great composite family and its bloom is a mass of flowers set very close together. They are purple to please the bees, for purple and blue are the colors which those busy little insects love best, and they are rich in nectar. In most sorts the tube of each floret is so long and narrow that crawlers find it difficult to get in after the nectar, and winged insects with short pro-boscides cannot reach it either. Nature means to save it, if she can, for the butterflies and bees.
But the little Canada thistle has flower-tubes shorter than those of other species, and hence its nectar can be drained by insects of many varieties. The honey rises into the throat of the flower, so as to be accessible even to insects with very short tongues, and hence it is visited by a large number of species. Muller records no fewer than eighty-eight.
The mechanism of the florets is like that in the dandelion. The long anthers are united into a tube, which closely surrounds the pistil, and the pollen is shed into this tube. The pollen-grains are covered with little points, so that they cling together, and the whole mass of them is pushed out at the top of the anther cylinder by the lengthening of the pistil. The pistil divides, at its tip, into two little arms, which are thickly clothed on their outsides with small pointed hairs. So, when the top of the pistil emerges from the anther-ring it is thickly covered, all over the outer surface, with pollen. In most instances this is soon removed, for the points on the pollen-grains cling to the hairy bodies of visiting insects. A little later the tips of the pistil separate so as to expose the sticky or stigmatic surfaces, and in this position it waits, open-armed, for a pollen-freighted friend. But if no insects visit the flower the arms of the pistil curve over, as do those of the dandelion, and fertilize themselves with home-made pollen. However, Canada thistles are rarely thus thrown upon their own resources, for they are immensely popular and entertain guests from dawn till dusk. As soon as pollen has reached its stigma, or when it begins to wither, the blossom bends downward and outward. Having had its day and its opportunity, it retires into the background to give a better chance to its younger sisters. The florets of the white clover (Fig. 95) have learned a like habit for the family good, and toward midsummer one may find a white-clover head with a single blossom standing straight up while all the rest are folded back against the stalk. Those which bend downward are fertilized florets enfolding the ripening seed, or unfertilized florets which have begun to wither. The one erect flower is a solitary-watcher, still in alert expectation of the hoped-for bee.
Fig. 95. - Gathered in latter summer.