Part 12

Meadows bright with clover-heads among the grasses, daisies, and buttercups in June resound with the murmur of unwearying industry and rapturous enjoyment. Bumblebees by the tens of thousands buzzing above acres of the farmer's clover blossoms should be happy in a knowledge of their benefactions, which doubtless concern them not at all. They have never heard the story of the Australians who imported quantities of clover for fodder, and had glorious fields of it that season, but not a seed to plant next year's crops, simply because the farmers had failed to import the bumblebee. After her immigration the clovers multiplied prodigiously. No; the bee's happiness rests on her knowledge that only the butterflies' long tongues can honestly share with her the brimming wells of nectar in each tiny floret. Children who have sucked them too appreciate her rapture. If we examine a little flower under the magnifying glass, we shall see why its structure places it in the pea family. Bumblebees so depress the keel either when they sip, or feed on pollen, that their heads and tongues get well dusted with the yellow powder, which they transfer to the stigmas of other flowers; whereas the butterflies are of doubtful value, if not injurious, since their long, slender tongues easily drain the nectar without depressing the keel. Even if a few grains of pollen should cling to their tongues, it would probably be wiped off as they withdrew them through the narrow slit, where the petals nearly meet, at the mouth of the flower. Bombus terrestris delights in nipping holes at the base of the tube, which other pilferers also profit by. Our country is so much richer in butterflies than Europe, it is scarcely surprising that Professor Robertson found thirteen Lepidoptera out of twenty insect visitors to this clover in Illinois, whereas Muller caught only eight butterflies on it out of a list of thirty-nine visitors in Germany. The fritillaries and the sulphurs are always seen about the clover fields among many others, and the "dusky wings" and the caterpillar of several species feeds almost exclusively on this plant.

"To live in clover," from the insect's point of view at least, may well mean a life of luxury and affluence. Most peasants in Europe will tell you that a dream about the flower foretells not only a happy marriage, but long life and prosperity. For ages the clover has been counted a mystic plant, and all sorts of good and bad luck were said to attend the finding of variations of its leaves which had more than the common number of leaflets. At evening these leaflets fold downward, the side ones like two hands clasped in prayer, the end one bowed over them. In this fashion the leaves of the white and other clovers also go to sleep, to protect their sensitive surfaces from cold by radiation, it is thought.

The ZIG-ZAG CLOVER, COW or MARL-GRASS (T. Medium), a native of Europe and Asia, now naturalized in the eastern half of the United States and Canada, may scarcely be told from the common red clover, except by its crooked, angular stems - often provokingly straight - by its unspotted leaves, and the short peduncle in which its heads are elevated above the calyx.

Farmers here are beginning to learn the value of the beautiful CRIMSON, CARNATION or ITALIAN CLOVER or NAPOLEONS (T. incarnatum), and happily there are many fields and waste places in the East already harboring the brilliant runaways. The narrow heads may be two and a half inches long. A meadow of this fodder plant makes one envious of the very cattle that may spend the summer day wading through acres of its deep bright bloom.

GOAT'S RUE; CAT-GUT; HOARY PEA or WILD SWEET PEA (Cracca Virginiana; Tephrosia Virginiana of Gray) Pea family

Flowers - In terminal cluster, each 1/2 in. long or over, butterfly-shaped, consisting of greenish, cream-yellow standard, purplish-rose wings, and curved keel of greenish yellow tinged with rose; petals clawed; 10 stamens (9 and 1); calyx 5-toothed. Stem: Hoary, with white, silky hairs, rather woody, 1 to 2 feet high. Leaves: Compounded of 7 to 25 oblong leaflets. Root: Long, fibrous, tough. Fruit: A hoary, narrow pod, to 2 in. long. Preferred Habitat - Dry, sandy soil, edges of pine woods. Flowering Season - June-July. Distribution - Southern New England, westward to Minnesota, south to Florida, Louisiana, and Mexico.

Flowers far less showy and attractive than this denizen of sandy wastelands, a cousin of the wisteria vine and the locust tree, have been introduced to American gardens. Striking its long fibrous root deep into the dry soil, the plant spreads in thrifty clumps through heat and drought - and so tough are its fibers they might almost be used for violin strings. As in the case of the lupine, the partridge pea and certain others akin to it, the leaves of the hoary pea "go to sleep" at night, but after a manner of their own, i.e., by lying along the stem and turning on their own bases.

In similar situations from New York south and southwestward, the MILK PEA (Galactia regularis; G. glabella of Gray) lies prostrate along the ground, the matted, usually branched stems sending up at regular intervals a raceme of rose-purple flowers in July and August from the axil of the trefoliate leaf.

TRAILING BUSH CLOVER (Lespedeza procumbens) Pea family

Flowers - Purplish pink or violet, veined, the butterfly-shaped ones having standard petal, wings, and keel, clustered at end of peduncles; the minute flowers lacking a corolla, nearly sessile. Calyx of 5 slender, nearly equal lobes. Stems: Prostrate, trailing, or sometimes ascending, woolly or downy, leafy. Leaves: Clover-like, trefoliate. Fruit: A very small, hairy, flat, rounded, acute pod. Preferred Habitat - Dry soil open, sandy places. Flowering Season - August-September. Distribution - Massachusetts to the Gulf, and westward to the Mississippi.

Springing upward from a mass of clover-like leaves, these showy little blossoms elevate themselves to arrest, not our attention, but the notice of the passing bee. As the claw of the standard petal and the calyx are short, he need not have a long tongue to drain the nectary pointed out to him by a triangular white mark at the base of the banner. Now, as his weight depresses the incurved keel, wherein the vital organs are protected, the stigma strikes the visitor in advance of the anthers, so that pollen brought on his underside from another flower must come off on this one before he receives fresh pollen to transfer to a third blossom. At first the keel returns to its original position when depressed; later it loses its elasticity. But besides these showy flowers intended to be cross-fertilized by insects, the bush clovers bear, among the others, insignificant-looking, tightly closed, bud-like ones that produce abundant self-fertilized seed. The petaliferous flowers are simply to counteract the inevitable evils resulting from close inbreeding. One usually finds caterpillars of the "dusky wings" butterfly feeding on the foliage and the similar tick trefoils which are its staple. At night the bush clover leaves turn upward, completely changing the aspect of these plants as we know them by day. Michaux named the group of flowers for his patron, Lespedez, a governor of Florida under the Spanish regime.

Perhaps the commonest of the tribe is the VIOLET BUSH CLOVER (L. violacea), a variable, branching, erect, or spreading plant, sometimes only a foot high, or again three times as tall. Its thin leaves are more elliptic than the decidedly clover-like ones of the preceding species; its rose-purple flowers are more loosely clustered, and the stems are only sparingly hairy, never woolly.

On the top of the erect, usually unbranched, but very leafy stem of the WAND-LIKE BUSH CLOVER (L. frutescens), the two kinds of flowers grow in a crowded cluster, and more sparingly from the axils below. The clover-like leaflets, dark green and smooth above, are paler and hairy below. Like the rest of its kin, this bush clover delights in dry soil, particularly in open, sandy places near woods of pine and oak. One readily distinguishes the SLENDER BUSH CLOVER (L. Virginica) by the very narrowly oblong leaves along its wand, which bears two kinds of bright rose flowers, clustered at the top chiefly, and in the axils.

Yellowish-white flowers, about a quarter of an inch long, and with a purplish-rose spot on the standard petal to serve as a pathfinder to the nectary, are crowded in oblong spikes an inch and a half long or less on the HAIRY BUSH CLOVER (L. hirta). The stem, which may attain four feet, or half that height, is usually branched; and the entire plant is often downy to the point of silkiness.

Dense clusters of the yellowish-white flowers of the ROUND-HEADED BUSH CLOVER (L. capitata) are seated in the upper axils of the silvery-hairy, wand-like stem. Pink streaks at the base of the standard petal serve as pathfinders, and its infolded edges guide the bee's tongue straight to the opening in the stamen tube through which he sucks.

WILD or SPOTTED GERANIUM or CRANE'S-BILL; ALUM-ROOT (Geranium maculatum) Geranium family

Flowers - Pale magenta, purplish pink, or lavender, regular, 1 to 1 1/2 in. broad, solitary or a pair, borne on elongated peduncles, generally with pair of leaves at their base. Calyx of 5 lapping, pointed sepals; 5 petals, woolly at base; 10 stamens; pistil with 5 styles. Fruit: A slender capsule pointed like a crane's bill. In maturity it ejects seeds elastically far from the parent plant. Stem: 1 to 2 ft. high, hairy, slender, simple or branching above. Leaves: Older ones sometimes spotted with white; basal ones 3 to 6 in. wide, 3 to 5 parted, variously cleft and toothed; 2 stem leaves opposite. Preferred Habitat - Open woods, thickets, and shady roadsides. Flowering Season - April-July. Distribution - Newfoundland to Georgia, and westward a thousand miles.

Sprengel, who was the first to exalt flowers above the level of mere botanical specimens, had his attention led to the intimate relationship existing between plants and insects by studying out the meaning of the hairy corolla of the common wild geranium of Germany (G. sylvaticum), being convinced, as he wrote in 1787, that "the wise Author of Nature has not made even a single hair without a definite design." A hundred years before, Nehemias Grew had said that it was necessary for pollen to reach the stigma of a flower in order that it might set fertile seed; and Linnaeus had to come to his aid with conclusive evidence to convince a doubting world that this was true. Sprengel made the next step forward, but his writings lay neglected over seventy years because he advanced the then incredible and only partially true statement that a flower is fertilized by insects which carry its pollen from its anthers to its stigma. In spite of his discoveries that the hairs inside the geranium's corolla protect its nectar from rain for the insect's benefit, just as eyebrows keep perspiration from falling into the eye; that most flowers which secrete nectar have what he termed "honey guides" - spots of bright color, heavy veining, or some such pathfinder on the petals - in spite of the most patient and scientific research that shed great light on natural selection a half-century before Darwin advanced the theory, he left it for the author of "The Origin of Species" to show that cross-fertilization - the transfer of pollen from one blossom to another, not from anthers to stigma of the same flower - is the great end to which so much marvelous mechanism is chiefly adapted. Cross-fertilized blossoms defeat self-fertilized flowers in the struggle for existence.

No wonder Sprengel's theory was disproved by his scornful contemporaries in the very case of his wild geranium, which sheds its pollen before it has developed a stigma to receive any; therefore no insect that had not brought pollen from an earlier bloom could possibly fertilize this flower. How amazing that he did not see this! Our common wild crane's-bill, which also has lost the power to fertilize itself, not only ripens first the outer, then the inner, row of anthers, but actually drops them off after their pollen has been removed, to overcome the barest chance of self-fertilization as the stigmas become receptive. This is the geranium's and many other flowers' method to compel cross-fertilization by insects. In cold, stormy, cloudy weather a geranium blossom may remain in the male stage several days before becoming female; while on a warm, sunny day, when plenty of insects are flying, the change sometimes takes place in a few hours. Among others, the common sulphur or puddle butterfly, that sits in swarms on muddy roads and makes the clover fields gay with its bright little wings, pilfers nectar from the geranium without bringing its long tongue in contact with the pollen. Neither do the smaller bees and flies which alight on the petals necessarily come in contact with the anthers and stigmas. Doubtless the larger bees are the flowers' true benefactors.

The so-called geraniums in cultivation are pelargoniums, strictly speaking.

In barren soil, from Canada to the Gulf, and far westward, the CAROLINA CRANE'S-BILL (G. Carolinianum), an erect, much-branched little plant resembling the spotted geranium in general features, bears more compact clusters of pale rose or whitish flowers, barely half an inch across. As their inner row of anthers comes very close to the stigmas, spontaneous self-fertilization may sometimes occur; although in fine weather small bees, especially, visit them constantly. The beak of the seed vessel measures nearly an inch long.

HERB ROBERT; RED ROBIN; RED SHANKS; DRAGON'S BLOOD (Geranium Robertianum) Geranium family

Flowers - Purplish rose, about 1/2 in. across, borne chiefly in pairs on slender peduncles. Five sepals and petals; stamens 10; pistil with 5 styles. Stem: Weak, slender, much branched, forked, and spreading, slightly hairy, 6 to i8 in. high. Leaves: Strongly scented, opposite, thin, of 3 divisions, much subdivided and cleft. Fruit: Capsular, elastic, the beak 1 in. long, awn-pointed. Preferreed Habitat - Rocky, moist woods and shady roadsides Flowering Season - May-October Distribution - Nova Scotia to Pennsylvania, and westward to Missouri.

Who was the Robert for whom this his "holy herb" was named? Many suppose that he was St. Robert, a Benedictine monk, to whom the twenty-ninth of April - the day the plant comes into flower in Europe - is dedicated. Others assert that Robert Duke of Normandy, for whom the "Ortus Sanitatis," a standard medical guide for some hundred of years, was written, is the man honored; and since there is now no way of deciding the mooted question, we may take our choice.

Only when the stems are young are they green; later the plant well earns the name of red shanks, and when its leaves show crimson stains, of dragon's blood.

At any time the herb gives forth a disagreeable odor, but especially when its leaves and stem have been crushed until they emit a resinous secretion once an alleged cure for the plague. Flies, that never object to a noxious smell, constantly visit the flower, and have their tongues guided through passages between little ridge-like processes on each petal to the nectar secreted by the base of the filaments at the base of each sepal. To prevent self-fertilization the five stigmas are folded close together when the flower opens, nor do they spread apart and become receptive until after the outer row of anthers, then the inner row, have shed their pollen. When the elastic carpels have ripened their seed, bang! go the little guns, scattering them far and wide.

WHITE OR TRUE WOOD~SORREL; ALLELULA (Oxalis acetosella) Wood-sorrel family

Flowers - White or delicate pink, veined with deep pink, about 1/2 in. long. Five sepals; 5 spreading petals rounded at tips; 10 stamens, 5 longer, 5 shorter, all anther-bearing; 1 pistil with 5 stigmatic styles. Scape: Slender, leafless, 1-flowered, 2 to 5 in, high. Leaf: Clover-like, of 3 leaflets, on long petioles from scaly, creeping rootstock. Preferred Habitat - Cold, damp woods. Flowering Season - May-July. Distribution - Nova Scotia and Manitoba, southward to North Carolina. Also a native of Europe.

Clumps of these delicate little pinkish blossoms and abundant leaves, cuddled close to the cold earth of northern forests, usually conceal near the dry leaves or moss from which they spring blind flowers that never open - cleistogamous the botanists call them - flowers that lack petals, as if they were immature buds; that lack odor, nectar, and entrance; yet they are perfectly mature, self-fertilized, and abundantly fruitful. Fifty-five genera of plants contain one or more species on which these peculiar products are found, the pea family having more than any other, although violets offer perhaps the most familiar instance to most of us. Many of these species bury their offspring below ground; but the wood-sorrel bears its blind flowers nodding from the top of a curved scape at the base of the plant, where we can readily find them. By having no petals, and other features assumed by an ordinary flower to attract insects, and chiefly in saving pollen, they produce seed with literally the closest economy. It is estimated that the average blind flower of the wood-sorrel does its work with four hundred pollen grains, while the prodigal peony scatters with the help of wind and insect visitors over three and a half millions!

Yet no plant, however economically inclined, can afford to deteriorate its species through self-fertilization; therefore, to overcome the evils of in-breeding, the wood-sorrel, like other plants that bear cleistogamous flowers, takes special pains to produce showy blossoms to attract insects, on which they absolutely depend to transfer their pollen from flower to flower. These have their organs so arranged as to make self-fertilization impossible.

Every child knows how the wood-sorrel "goes to sleep" by drooping its three leaflets until they touch back to back at evening, regaining the horizontal at sunrise - a performance most scientists now agree protects the peculiarly sensitive leaf from cold by radiation. During the day, as well, seedling, scape, and leaves go through some interesting movements, closely followed by Darwin in his "Power of Movement in Plants," which should be read by all interested.

Oxalis, the Greek for sour, applies to all sorrels because of their acid juice; but acetosella = vinegar salt, the specific name of this plant, indicates that from it druggists obtain salt of lemons. Twenty pounds of leaves yield between two and three ounces of oxalic acid by crystallization. Names locally given the plant in the Old World are wood sour or sower, cuckoo's meat, sour trefoil, and shamrock - for this is St. Patrick's own flower, the true shamrock of the ancient Irish, some claim. Alleluia, another folk-name, refers to the joyousness of the Easter season, when the plant comes into bloom in England.

VIOLET WOOD-SORREL (Oxalis violacea) Wood-sorrel family

Flowers - Pinkish purple, lavender, or pale magenta; less than 1 in. long; borne on slender stems in umbels or forking clusters, each containing from 3 to 12 flowers. Calyx of 5 obtuse sepals; 5 petals; 10 (5 longer, 5 shorter) stamens; 5 styles persistent above 5-celled ovary. Stem: From brownish, scaly bulb 4 to 9 in. high. Leaves: About 1 in. wide, compounded of 3 rounded, clover-like leaflets with prominent midrib, borne at end of slender petioles, springing from root. Preferred Habitat - Rocky and sandy woods. Flowering Season - May-June. Distribution - Northern United States to Rocky Mountains, south to Florida and New Mexico; more abundant southward.

Beauty of Leaf and blossom is not the only attraction possessed by this charming little plant. As a family the wood-sorrels have great interest for botanists since Darwin devoted such exhaustive study to their power of movement, and many other scientists have described the several forms assumed by perfect flowers of the same species to secure cross-fertilization. Some members of the clan also bear blind flowers, which have been described in the account of the white wood-sorrel given above. Even the rudimentary leaves of the seedlings "go to sleep" at evening, and during the day are in constant movement up and down. The stems, too, are restless; and as for the mature leaves, every child knows how they droop their three leaflets back to back against the stem at evening, elevating them to the perfect horizontal again by day. Extreme sensitiveness to light has been thought to be the true explanation of so much activity, and yet this is not a satisfactory theory in many cases. It is certain that drooping leaves suffer far less from frost than those whose upper surfaces are flatly exposed to the zenith. This view that the sleep of leaves saves them from being chilled at night by radiation is Darwin's own, supported by innumerable experiments; and probably it would have been advanced by Linnaeus, too, since so many of his observations in "Somnus Plantarum" verify the theory, had the principle of radiation been discovered in his day. The violet wood-sorrel produces two sorts of perfect flowers reciprocally adapted to each other, but on different plants in the same neighborhood. The two are essentially alike, except in arrangement of stamens and pistil; one flower having high anthers and low stigmas, the other having lower anthers and higher stigmas; and as the high stigmas are fertile only when pollenized with grains from a flower having high anthers, it is evident insect aid to transfer pollen is indispensable here. Small bees, which visit these blossoms abundantly, are their benefactors; although there is nothing to prevent pollen from falling on the stigmas of the short-styled form. Hildebrand proved that productiveness is greatest, or exists only, after legitimate fertilization. To accomplish cross-pollination, many plants bear flowers of opposite sexes on different individuals; but the violet wood-sorrel's plan, utilized by the bluet and partridge-vine also, has the advantage in that both kinds of its flowers are fruitful.

COMMON, FIELD, or PURPLE MILKWORT; PURPLE POLYGALA (Polygala viridescens; P. sanguinca of Gray) Milkwort family

Flowers - Numerous, very small, variable; bright magenta, pink, or almost red, or pale to whiteness, or greenish, clustered in a globular clover-like head, gradually lengthening to a cylindric spike. Stem: 6 to 15 in. high, smooth, branched above, leafy. Leaves: Alternate, narrowly oblong, entire. Preferred Habitat - Fields and meadows, moist or sandy. Flowering Season - June-September. Distribution - Southern Canada to North Carolina, westward to the Mississippi.

When these bright clover-like heads and the inconspicuous greenish ones grow together, the difference between them is so striking it is no wonder Linnaeus thought they were borne by two distinct species, sanguinea and viridescens, whereas they are now known to be merely two forms of the same flower. At first glance one might mistake the irregular little blossom for a member of the pea family; two of the five very unequal sepals - not petals - are colored wings. These bright-hued calyx-parts overlap around the flower-head like tiles on a roof. Within each pair of wings are three petals united into a tube, split on the back, to expose the vital organs to contact with the bee, the milkwort's best friend.

Plants of this genus were named polygala, the Greek for much milk, not because they have milky juice - for it is bitter and clear - but because feeding on them is supposed to increase the flow of cattle's milk.