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IVY (A.S. ifig, Ger. Epheu, perhaps c...

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Originally appearing in Volume V15, Page 101 of the 1911 Encyclopedia Britannica.
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IVY (A.S. ifig, Ger. Epheu, perhaps connected with apium, anent)  , the collective designation of certain See also:species and varieties of Hedera, a member of the natural See also:order Araliaceae . r . See also:Flower . 2 . See also:Fruit . There are fifty species of See also:ivy recorded in See also:modern books, but they may be reduced to two, or at the most, three . The See also:European ivy, Hedera See also:Helix (fig . I), is a plant subject to See also:infinite variety in the forms and See also:colours of its leaves, but the tendency of which is always to a three- to five-lobed See also:form when climbing and a See also:regular ovate form of See also:leaf when producing flower and fruit . The See also:African ivy, H. canariensis, often regarded as a variety of H . Helix and known as the Irish ivy, is a native of See also:North See also:Africa and t'-e adjacent islands . It is the cornmon large-leaved climbing ivy, and also varies, but in a less degree than H . Helix, from which its leaves differ in their larger See also:size, See also:rich deep See also:green See also:colour, and a prevailing tendency to a five-lobed outline .

When in fruit the leaves are usually three-lobed, but they are sometimes entire and broadly ovate . The See also:

Asiatic ivy, H. colchica (fig . 2), now considered to be a form of H . Helix, has ovate, obscurely three-lobed leaves of a coriaceous texture and a deep green colour; in the See also:tree or fruiting form the leaves are narrower than in the climbing form, and without any trace of lobes . Distinctive characters are also to be found in the appendages of the pedicels and calyx, H . Helix having six-rayed stellate hairs, H. canariensis fifteen-rayed hairs and H. colchica yellowish two-lobed scales . The Australian ivy, H. australiana, is a small glabrous See also:shrub with pinnate leaves . It is a native of See also:Queensland, and is practically unknown in cultivation . It is of the utmost importance to See also:note the difference of See also:char- acters of the same species of ivy in its two conditions of climbing and fruiting . The first See also:stage of growth, which we will suppose to be from the See also:seed, is essentially scandent, and the leaves are lobed more or less . This stage is accompanied with a plentiful See also:production of the claspers or modified roots by means of which the plant becomes at- tached and obtains sup- See also:port . When it has reached the See also:summit of the tree or See also:tower, the stems, being no longer able to maintain a per- pendicular attitude, fall over and become See also:horizontal or pendent .

Coincidently with this See also:

change they cease to produce claspers, and the leaves are strik- ingly modified in form, being now narrower and less lobed than on the ascending stems . In due See also:time this tree-like growth produces terminal umbels of greenish See also:flowers, which have the parts in See also:fives, with the styles See also:united into a very See also:short one . These flowers are succeeded by smooth See also:black or yellow berries, containing two to five seeds . The yellow-berried ivy is met with in See also:northern See also:India and in See also:Italy, but in northern See also:Europe it is known only as a curiosity of the See also:garden, where, if sufficiently sheltered and nourished, it becomes an exceedingly beautiful and fruitful tree . It is stated in books that some forms of sylvestral ivy never flower, but a negative See also:declaration of this See also:kind is valueless . Sylvestral ivies of See also:great See also:age may be found in See also:woods on the western coasts of See also:Britain that have apparently never flowered, but this is probably to be explained by their inability to surmount the trees supporting them, for until the plant can spread its branches horizontally in full daylight, the flowering or tree-like growth is never formed . A question of great See also:practical importance arises out of the relation of the plant to its means of support . A moderate growth of ivy is not injurious to trees; still the tendency is from the first inimical to the prosperity of the tree, and at a certain stage it becomes deadly . Therefore the growth of ivy on trees should be kept within reasonable See also:bounds, more especially in the See also:case of trees that are of See also:special value for their beauty, See also:history, or the quality of their See also:timber . In regard to buildings clothed with ivy, there is nothing to be feared so See also:long as the plant does not penetrate the substance of the See also:wall by means of any fissure . Should it thrust its way in, the natural and continuous expansion of its several parts will necessarily hasten the decay of the edifice . But a See also:fair growth of ivy on See also:sound walls that afford no entrance beyond the superficial See also:attachment of the claspers is, without any exception whatever, beneficial .

It promotes dryness and warmth, reduces to a minimum the corrosive See also:

action of the See also:atmosphere, and is altogether as conservative as it is beautiful . The economical uses of the ivy are not of great importance . The leaves are eaten greedily by horses, See also:deer, See also:cattle and See also:sheep, and in times of scarcity have proved useful . The flowers afford a See also:good See also:supply of See also:honey to bees; and, as they appear in autumn, they occasionally make amends for the shortcomings of the See also:season . The berries are eaten by See also:wood pigeons, blackbirds and thrushes . From all parts of the plant a balsamic See also:bitter may be obtained, and this in the form of hederic See also:acid is the only preparation of ivy known to chemists . In the garden the uses of the ivy are innumerable, and the least known though not the least valuable of them is the cultivation of the plant as a See also:bush or tree, the fruiting growth being selected for this purpose . The variegated tree forms of H . Helix,with leaves of creamy See also:white, See also:golden green or rich deep See also:orange yellow, soon prove handsome See also:miniature trees, that thrive almost as well in smoky See also:town gardens as in the pure See also:air of the See also:country, and that no See also:ordinary See also:winter will injure in the least . The tree-form of the Asiatic ivy (H. colchica) is scarcely to be equalled in beauty of leafage by any See also:evergreen shrub known to See also:English gardens, and, although in the course of a few years it will attain to a stature of 5 or 6 ft., it is but rarely we meet with it, or indeed with tree ivies of any kind, but little See also:attention having been given to this subject until See also:recent years . The scandent forms are more generally appreciated, and are now much employed in the formation of marginal lines, screens and trained pyramids, as well as for clothing walls . A very striking example of the capabilities of the commonest ivies, when treated artistically as garden See also:plants, may be seen in the Zoological Gardens of See also:Amsterdam, where several paddocks are enclosed with wreaths, garlands and bands of ivy in a most picturesque manner .

About sixty varieties known in gardens are figured and described in The Ivy, a Monograph, by See also:

Shirley Hibberd (1872) . To cultivate these is an extremely See also:simple See also:matter, as they will thrive in a poor See also:soil and endure a considerable See also:depth of shade, so that they may with See also:advantage be planted under trees . The See also:common Irish ivy is often to be seen clothing the ground beneath large See also:yew trees where grass would not live, and it is occasionally planted in graveyards in See also:London to form an See also:imitation of grass See also:turf, for which purpose it is admirably suited . The ivy, like the See also:holly, is a scarce plant on the See also:American See also:continent . In the northern United States and See also:British See also:America the winters are not more severe than the ivy can endure, but the summers are too hot and dry, and the requirements of the plant have not often obtained attention . In districts where native ferns abound the ivy will be found to thrive, and the varieties of Hedera Helix should have the preference . But in the drier districts ivies might often be planted on the north See also:side of buildings, and, if encouraged with See also:water and careful training for three or four years, would then grow rapidly and See also:train them-selves . A strong See also:light is detrimental to the growth of ivy, but this enhances its value, for we have no See also:hardy plants that may be compared with it for variety and beauty that will endure shade with equal See also:patience . The North American See also:poison ivy (poison See also:oak), Rhus Toxicodendron (nat. order Anacardiaceae), is a climber with pinnately See also:compound leaves, which are very attractive in their autumn colour but poisonous to the See also:touch to some persons, while others can handle the plant without injury . The effects are redness and violent itching followed by See also:fever and a vesicular eruption . The ground ivy, Nepeta Glechoma (nat. order See also:Labiatae), is a small creeping plant with rounded crenate leaves and small See also:blue-See also:purple flowers, occurring in hedges and thickets .

End of Article: IVY (A.S. ifig, Ger. Epheu, perhaps connected with apium, anent)
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