Scientific American Supplement, No. 430, March 29, 1884 by Various
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page 5 of 132 (03%)
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(devil's hair) in French, and gold thread in English. Because of their
destructive nature they have likewise been called by the unpoetic name of hellweed; and, for the reason that they embrace their host plants so closely, they have been called love weed and love vine. When a seed of _Cuscuta_, germinates, no cotyledons are to be distinguished. This peculiarity, however, the plant has in common with other parasites, and even with some plants, such as orchids, that vegetate normally. The radicle of the dodder fixes itself in the earth, and the little stem rises as in other dicotyledons; but soon (for the plantlet could not live long thus) this stem, which is as slender as a thread, seeks support upon some neighboring plant, and produces upon its surfaces of contact one or more little protuberances that shortly afterward adhere firmly to the support and take on the appearance and functions of cupping glasses. At this point there forms a prolongation of the tissue of the dodder--a sort of cone, which penetrates the stalk of the host plant. After this, through the increase of the stem and branches of the parasite, the supporting plant becomes interlaced on every side, and, if it does not die from the embraces of its enemy, its existence is notably hazarded. It is possible for a _Cuscuta_ plant to work destruction over a space two meters in diameter in a lucern or clover field; so, should a hundred seeds germinate in an acre, it may be easily seen how disastrous the effects of the scourge would prove. These enemies of our agriculture were scarcely to be regarded as injurious not very many years ago, for the reason that their sources of development were wanting. Lucern and clover are comparatively recent introductions into France, at least as forage plants. Other cultures are often sorely tried by the dodder, and what is peculiar is that there are almost always species that are special to such or such a plant, so that |
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