Epiphyte

“ Of all the plants of such regions the epiphytes are the most light-demanding. They must not be mistaken for parasites, as they have roots of their own through which they absorb nourishment, mostly as water vapor, but also as liquid water held in the bark and refuse in which they grow. Thousands of orchids are epiphytes, also ferns, and, only in the American tropics, thousands of different relatives of the pineapple. Many of the latter are among the most gorgeously colored of all plants, their superb foliage being much sought after and the specimens largely grown in our greenhouses. ”

“ Plants are usually terrestrial, that is, growing on earth, or aquatic, i. e. growing in water; but sometimes they may be found attached by their roots to other plants, in which case they are epiphytes when simply growing upon other plants without penetrating into their tissue, parasites when their roots penetrate into and derive more or less nutriment from the plant to which they are attached. ”

“ Most of the larger species of marine Rhodophyceae are attached by means of a disc to rocks, stones or shells. Many are epiphytic on other algae, more especially the larger Phaeophyceae and Rhodophyceae. As in the case of epiphytic brown seaweeds, the rhizoids of the epiphyte often penetrate the substance of the supporting alga. Some Red Algae find a home in the gelatinous substance of Flustra, Alcyonidium and other polyzoa, only emerging for the formation of the reproductive organs. ”

“ These splendid orchids and other epiphytes grow singly. One sees one and not another, there are no broad masses of color to blaze in the distance, the scents are heavy and overpowering, the wealth is embarrassing. ”

“ No brief description can adequately portray the marvellous variety and magnificence of the flora of the tierras calientes. Its forests are not composed of one or a few dominating species, as in the cold temperate zone, but of countless genera and species closely interwoven together—a confused mass of giant trees, lianas and epiphytes struggling to reach the sunlight. This struggle for existence has completely changed the habits of some plants, turning the palm and the cactus into climbers, and even some normal species into epiphytes. ”

“ A question which it will be necessary to leave to wiser heads, only observing that these epiphytes do appear, under certain atmospheric conditions, to invade some plants that had previously seemed to be in perfect health. That they are transported upon the air, in the form of very minute sporules, is unquestioned, and that their growth is dependent upon certain atmospheric conditions, is equally admitted, but whether they induce disease, or are only able to take possession of a plant that is not in a perfectly healthy condition, does not yet appear so clear. ”

“ It should be distinctly understood that, in the case of true epiphytes, there is no need for manures, and, that artificial chemical manures are almost certain to bring about disastrous results, the final collapse being in proportion to the potency of the stimulant used and the recklessness of the grower. Where rain-water can be obtained and stored for use throughout the season, it is safest and most satisfactory to rely on this alone, except for some terrestrial Orchids. ”

“ It may be unable to penetrate into the plant, and finding no suitable food outside it dies: or it may be satisfied with the traces of organic matter on the epidermis and then lives the life of a saprophyte. Or it may be able to establish a hold-fast on the tender epidermal surface, but without entering the cells, and irritate the developing organ by contact stimulation, inducing slight abnormalities; if in its further, purely superficial growth such an epiphyte covers large areas of the leaf, and especially if the hyphae are dark coloured—e.g. ”

“ Each kind of orchid has its own kind of insect, and all of the elaboration of the flower is connected with this fact. In greenhouses orchids are among the most prized of plants, on account of the showy colors and the strange forms of the flowers, the most conspicuous being the epiphytes from the tropical forests. ”

“ Epiphytes abound in the tropics. Certain orchids are among the best known examples (Fig. 37) . The Spanish moss or tillandsia of the South is another. Mosses and lichens that grow on trees and fences may also be called epiphytes. In the struggle for existence, the plants probably have been driven to these special places in which to find opportunity to grow. Plants grow where they must, not where they will.
Suggestions.—114. Is a puffball a plant? Why do you think so? 115. Are mushrooms ever cultivated, and where and how? 116. In what locations are mushrooms and toadstools usually found? ”

“ The majority live in the Tropics and occur, especially, as epiphytes on trees or in the crevices of rocks, to which they are attached by aerial roots. These aerial roots, like those of Araceæ, are covered by several layers of spirally-thickened cells (tracheides) which contain air and form the velamen—an apparatus to absorb moisture from the air. The roots have a white appearance when the cells are filled with air, which changes to a greenish hue when they are filled with water, the chlorophyll then shining through. ”

“ Botrytis, &c. (Mildew) .—Under this head we include a multitude of epiphytes, to which the terms mildew, mealdew, mehlthau (Germ.) are applicable. They appear to the naked eye as patches of white [189] dust or meal on the leaves and stems of the affected plants. With the microscope we see that they are beautifully-organized plants, having a kind of rootlet (mycelium) or spawn entering the tissues of the living plants on which they grow, and delicate pedicels supporting spores at the externally visible portion of the plant. ”

“ In Epiphytes, or plants growing in the air, attached to the trunks of trees, such as orchids of warm climates, the aerial roots produced do not reach the soil; they continue always aerial and greenish, and they possess stomata. ”

“ Again: it will be impossible to enter into details of the different species of epiphytes. We shall hope, therefore, to elucidate their natural history, in so far as the farmer is concerned, by pointing out the more general facts connected with the following forms:—
1. ”

“ As the saltness of the water decreases, in ascending the river, the mangroves give way gradually to a variety of other shrubs and trees, supporting many climbing plants and with their branches often loaded with epiphytes. These epiphytic growths, comprising an astonishing variety of ferns and orchids, and other less familiar types, are a marked feature of this intensely humid region. ”

“ When grown on their own roots, Epiphyllums are useful for planting in wire baskets intended to hang near the glass; large and very handsome specimens form in a few years, if young rooted plants are placed rather thickly round the sides of the baskets, and grown in a warm house. Epiphyllums are employed with good effect for covering walls, which are first covered with peaty soil by means of wire netting, and then cuttings of the Epiphyllums are stuck in at intervals of about 1 ft. ”

“ I am afraid it has been rather a difficult history to follow step by step, and yet it is perfectly clear when once we master the succession of growths. Starting from a spore, the thread-mass or protonema gives rise to the moss-stems forming the dense green carpet, then the green flowers on some of the leaf-stems give rise to a plant-egg, which roots itself in the stem, and grows into a perfect plant without leaves, bearing merely the urn in which fresh spores are formed, and so the round goes on from year to year. ”

“ As the species and genera unite freely with each other, it is possible to produce, by means of grafting, some very extraordinary-looking plants, and to a lover of the incongruous and "queer," these plants will afford much interest and amusement. Besides the above, we graft Epiphyllums, and the long drooping Cereuses, such as C. flagelliformis, because of their pendent habit, and which, therefore, are seen to better advantage when growing from the tall erect stem of some stouter kind, than if allowed to grow on their own roots. ”

“ For plants with weak stems, stakes will be necessary, and even stout-stemmed kinds, when their roots are not sufficient to hold them firmly, will do best if fastened to one or two strong stakes till they have made new roots and got firm hold of the soil. Epiphyllums, when grown as standards, should be tied to strong wire supports, those with three short, prong-like legs being most desirable, as, owing to the weight of the head of the plant, a single stake is not sufficient to hold the whole firmly. ”

“ The cells grow smaller and more compact toward the outside of the section, until there are no spaces of any size between those of the outside or rind. The cells contain small chloroplasts like those of the higher plants, but owing to the presence of the brown pigment found in all of the class, in addition to the chlorophyll, they appear golden brown instead of green.
No non-sexual reproductive bodies are known in the rock weeds, beyond small branches that occur in clusters on the margins of the main branches, and probably become detached, forming new plants. ”

“ In fact, if the atmosphere in which the plants are placed be kept a little moist, it will not be necessary to water them till signs of fresh growth are perceived. For Epiphyllums and Rhipsalis, water will be required earlier than this; but even they are best left for a few days without water, after they have been repotted. As soon as fresh growth is perceived, the plants may be well watered, and from this time water may be supplied as often as the soil approaches dryness. ”

“ This surface layer in the typically subaerial “shoot” of the sporophyte in Pteridophytes and Phanerogams is known as the epidermis, though the name is restricted by some writers, on account of developmental differences, to the surface layer of the shoot of Angiosperms, and by others extended to the surface layer of the whole plant in both these groups. On the other hand, we have (2) an internal differentiation of conducting tissue, the main features of which as seen in the gametophyte of Bryophytes have already been fully described. ”

“ Leaf-rolling.—The leaves of Beeches, Poplars, Limes, and many other plants, instead of opening out flat, are often rolled in from the margins, or from the apex, by various species of Phytoptus, Cecidomyia, or other insects, which puncture or irritate the epidermis in the young stages and so arrest its expansion in proportion to the other tissues. According as the lower or upper surface is attacked the rolling is from the morphologically upper surface downwards, or vice versa. Very often the mesophyll is somewhat thickened where rolled and Erineum-like hairs may be developed—e.g. ”

“ The seed absorbs water, and the protoplasm of the embryo renews its activity, beginning to feed upon the nourishing substances in the cells of the endosperm. The embryo rapidly increases in length, and the root pushes out of the seed growing rapidly downward and fastening itself in the soil (G, r) . Cutting the seed lengthwise we find that the leaves have increased much in length and become green (one of the few cases where chlorophyll is formed in the absence of light) . ”

“ The Epiphyllums here are grown for flowering in the conservatory, and are usually gay from the first week in November till February. During the remainder of the year, they occupy a three-quarter span-roof house, in which an intermediate temperature is maintained. All our Epiphyllums are grafted on the Pereskia aculeata. We graft a few at intervals of two or three years, so, if any of the older plants become sickly or shabby, they are thrown away, and the younger ones grown on. Some of the stocks are worked to form pyramids, and some to form standards. ”

“ Smaller plants may be kept in position by means of a single upright stake, which should be long enough to stand an inch or two above the head of the plant, so that the stoutest branches may be supported by attaching a piece of matting to them, and fastening it to the top of the stake. In the remarks upon grafting we mentioned the large pyramidal specimens of Epiphyllum which are grown by some cultivators for exhibition purposes ”

“ Epipactis palustris; curious shape of the labellum and its importance in the fructification of the flower—other species of Epipactis—Epipogium—Goodyera repens—Spiranthes autumnalis; perfect adaptation by which the pollen of a younger flower is carried to the stigma of an older flower on another plant—Listera ovata; sensitiveness of the rostellum; explosion of viscid matter; action of insects; perfect adaptation of the several organs—Listera cordata—Neottia nidus-avis; its fertilisation effected in the same manner as in Listera—Thelymitra, self-fertile. ”

“ The Genus Epidendrum, takes its Generic title from its place of growth, being what Botanists term parasitical, that is, growing on another plant; which is the case, with most of the species of this Genus: yet is cultivated here with success, by planting it in a mixture of rotten wood, and loam. ”

“ Intense xerophytes and hydrophytes are much more fixed than mesophytes, though the intensity of the stimulus has doubtless as great an influence as its duration. Composites, labiates, grasses, orchids, etc., are less plastic than ranals, rosals, etc., but there are many exceptions to the apparent rule that fixity increases with taxonomic complexity. ”

“ The aphids attack the opening buds, the young fruits, the growing shoots, and the leaves, sucking the plant juices from the succulent parts by means of long, very slender, tube-like beaks, which they thrust through the skins of the affected organs into the soft tissues beneath. ”