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WILD FLOWERS [65]

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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
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