PLANT EDUCATION AND ITS RESULTS.

Evening Star, Issue 12883, 4 August 1906, Page 11

PLANT EDUCATION AND ITS RESULTS.

; , In a recent issue of the 'Evening Star' there appeared a paragraph relating a strange suggestion made by a French agriculturist, M. Antoine Ladue, to his Government. He wished a prize to be offcrod for a practicaVo scheme for the education of trees to tie -purpose that they might restrain themselves from sprouting until the frosts of early spring were over. At first glance the idea seems reminiscent of Humpty-Dumpry's remarks to Alice in 'Through the Looking-glass.' yet it is not altogether ridiculous. The next veneration may find its realisation quite feasible. It is. a biological fact that there is no real line of demarcation between animals and plants. All are collections—differently arranged, it is true—of colonies of. protophsta To the chemist each of them is a mixture of cellulose, albuminoids, water, and mineral mat'er. Psychologically Man is distinguished from the "lower" animals by the possession of "soul." It is tTue that some exotic schools of thought would award this to all creatures capible of independent movement, while certain sects have denied its possession by the female of the human genus. But we may take it that our readers btc generally convinced that Man is thus differentiated. It yet remains an established fact that it is quite posible to inculcate foreign habits to most mammals and many birds. A man, a dog, or a canary can be trained by hope of reward or fear of punishment. Why not a pant? There are many things for which Man will put forth his utmost energies. We can d-uw from him his. best by the offer of spiritual, intellectual, or material prizes. We can spur him by shame or physical discomfort. A dog, again, can be controlled by the promise of de'iearies or by fear of the whip. Even so gigantic an animal as the elephant may be goaded or coaxed with a bundle of sugar cane, and birds are equally amenab'e to discipline of a similar character. With plants, the rewards we can offer are purely negative. We can only requite disobedience with death. It is, however, true that a solution of is necessary a.t certain periods of a plant's existence, and that the artificial supplying of this at a critical moment might serve as an encouragement and incentive to do certain work which, nna-sisted, it might neg'ect. The ear'y botanist confined his labors to the consideration of " useful " plants—that i* to say, plants that would furnish food and mrdicine for himself and hw» friends, or poiron for those who inronvenr'nerd him. This mental attitude ruled until the fifteenth century. Meanwhile, the theoretical investhzrtor bus ! ed himself in interminable discussions with his kind as to the meaning of the names which had been .allotted to different varieties by Greek and Li tin writers. As the earliest of thei»e (Theopbrastus) wrote about 300 8.C., it is evident that the pundit found plenty of occupation. Then Charles de I'Eclusc (Clusrns) shook himself free from the tramme'e of casuistry and honestly set about making the personal acquaintance of the flora of Europe. Many observers of like bent followed bim, and the numbpr of species known stendily increased, until in the early years of the eighteenth century it amounted to 10.000. Then Linnaeus to collate the immense mass of undigested data thus accumuhted, and evolved a scheme of classification which set botanical science on a firm footing. Long before this Leeuwenhoek bad comirenced the u?e of the mienreope in biological research, but at first his discoveries were scoffed at r« delusions. Robert Hooke, however, in 1667 convinced the Royal Society of England of their truth by ocular demonstration, and thenceforward the microscope lent its aid to good purpose. At the present day some ?00,000 plants are differentiated. Plant'? have many characteristics in common with Man. They require food and drink, and to obtain there they will grow—their only method of progression—toward l ! the spot where tlie nutrition can be obtained. Their behaviour undei difficulties, the way in _ which their roots turn and twist to avoid obstacles, seek out crevices in rock, and grasp pieces of earth and stones which contain what they are seeking, make it appear as if they possessed something which informed them where to greatest advantage they should forage. Close observers are ratisfied that plants have within them some force, inatinct, or a dim form of reasoning power—call it what you will—which governs their actions. They require rest also. The trees on the Victoria Embankment drooped and died soon ifter the installation there of the electric light. Under the influence of this pseudosunlight they were growing both day and night—" working double-tides," in fact—and naturally enough their constitutions broke down, and they eventually died. Each plant carries within itself innumerable latent tendencies, undeveloped, it is true, but yet present for all that. Occasionally one of these may sjiow itself as a freak. A splash of unwonted color in a flower bed, or a whiff of strange perfume, an "accidental" fmit of unusual size or peculiar flavor will be a manifestation of the existence of one of these forgotten traits. Any of these signs may be noted and followed up by a modem horticulturist. Sometimes the revelations that result make us outsiders pause in amazement. When spring, that season'beloved of the poet, again comes round the trees and plants which have been as it were asleep throughout the dreary months of winter burst into bloom, and are ready to carry on tJie -work of the propagation of their species. The " stamen," an organ varying in shape and position in each variety, will now be found to be covered with " pollen." This term is not particularly apt, for "pollen" simply means "flour," and though in the majority of cases this substance is a dust, in many others .it is wf a gummy nature, sometimes granulated. The " dehiscence," the opening and exocsure of the pollen, mostly takes place during the early hours of the day, but with some oats and grasses it occurs fairly late in the afternoon. In the nettle and others the pollen is actually ejected at the dehiscence, but it usually remains in such a position as to be subject to the action of the passing winds or intruding birds and insects. Thence it is removed _ by these agents, and though much of it is lost, some eventually reaches another flower. Here it is received by an organ called a " stigma," and if this is in a receptive condition, under the action of certain sugary matters secreted by the plant—referred to in an earlier paragraph—the protoplast of the pollen combines with the ooplost beneath the stigma, and fertilisation proceeds, a seed eventually resulting. A sine qua non is thus that both the stamen and the stigma should be in an appropriate condition. It is impossible to say definitely how long these states continue. Some pollen loses its vita! properties in a few days. On the other hand, the Arabs regularly out by a quantity of the pollen of the date palm to ensure the next year's fertilisation should—as sometimes happens—the stamens fail to develop. The length of the period of the stigma's fitness also varies, though within narrower limits. Suffice it to say that the right moment is easily recognised by a man who has lived among flowers. The above explanation may appear bare to readers conversant with the subject, but it will serve for the purposes of this article^ In the case of a field of uniform soil and equally well Irrigated in all parts, and planted with com. one would expect such a cross-porinarion to occur from the silks of one plant to the tassels of every other that all individual characteristics would be ultimately lost. Such, speaking broadly, would be the case. If, however, the pollen from the smaller, weaker, or generally less promising plants was prevented bv screens, coverings, etc., from interfering with plants of a superior clas<—if /ear the seeds of the best specimens were again isolated, and a similar course was followed for several seasons, the logical result would be that a plant would be produced very greatly superior to the average of its ancestry. This has E roved to be the case in actual practice oth with cereals and plants of other classes. The orange known to ourselves—and to our Forebears for many centuries for that matter—as a succulent fruit oriertaally reached Western Europe as a

entail and bitter berry. One can go a' step farther, and introduce by hand pollen from a plant of the same species but growing in a different field, in a different district, it may be even in a foreign country with a dissimilar climate. This branch of A—lied Botany has been much developed of recent years, notably bv Luther Burbank, at Sebastopol (Oul.). Thr* man is a lover of Nature, a close observer, and a horticulturist of untiring perseverance. By the methods outlined above he has produced from the thorny cactus, a vegetable pest of sub-tropical regions, a plant which will grow in almost any climate, yielding delicious fruits in great quantity, and with a leaf eminently suitable for the making of conserves. The modus operandi was to fertilise an individual plant seeming to want to bear truit with pollen from one which showed a tendency to thornlessness. It is hardly too much to say that he "encouraged" the thornless cactus by destroying the ethers which seemed to show no signs of improvement. If Mr Burbank had but united commercial acumen to his other qualities, thfs plant alone would have made his fortune, but he dees not appear to be a business man, and seeds from his garden are only to be procured with difficulty. This cr ss-fertilisaticn may be carried a step_ further still, and two nlants of totally dissimiliar species and of habitats widely remote may be forced to unite. The seeds from these would then be sown. The results might show plants possessing the characteristics of both sides in equal or unequal degrees. Atavism might effect the production of species unlike either progenitor. The seeds thus obtained would in due course be set the following year. In many cases they would prove unfertile, but not in all, the rule of the sterility of hybrids being among plants not so invariable as with animals. After a few years the whole of the plants—perhaps many thousands by this time—would be overhauled, and only th< se displaying most beauty, virilitv. and -fecundity wculd be saved ; the remainder would be burnt. For the " white blackberry," for example, Burbank, saved only one plant out of 65.000. As is to be expected, some of his successes have only been partial, and occasionally the isolated freaks produced have been magnified into a class Specimens of his core Jess apple were sent to the Horticultural Srcietv in London, but on being opened proved to be anythinc but coreless. A recent cable from Lordcn stated that some specimens of his pipless orange and " pomato," grown in South Africa, had been exhibited at a recent show of this s eietv. and, it i 9 to be presumed, had passed muster. This " oomato" is a cross between a tomato and a potato, and is said to make a sunerlative salad. _ Another notable example of his work is an inmr-ved prune, five times the size of the ordinary French variety. Reverting to the or>ening paragraph of this article, it may be stated that a certain class of plant—the meadow saffrm is a member—buries itself at the approach of winter. The harder the frcst the deeper the roots are found. It would seem almost as if the plant knew when it was feeling cold, and had some idea of the degree of severity to expect. Another—an aquatic plant this time, the water soldier —will sink to the bottom of the lake on which it ordinarily lives, and lie snug there till snring comes again. When one considers these, and remembers what striking results have already been effected, it does not seem beynd the bunds of possibility that the French horticulturist's nrize may eventually be won. Professor Kerner Von Marilaun, of the University of Vienna, a world-renowned authority, emphasises the value of imaginative power in the investigator in this branch of science. One may be excused. then, perhaos, for projecting the " Nurse Tree" of the future. In the forests of Africa grows the " Cow Tree." secr'ting a juice distantly resembling milk. If this secretion could be enriched with resnect to its phosphates and fats, and the tree crossed with>.say, the helly. a tired mother could leave her babv in perfect security under its shade. If flies were anticipated some strain of pitcher-plant or other fly-catcher—there are 500 to select from—could be introduced. Da.re any person in possession of all the evidence of nast achievements scut even this wild idea as an impossibility?— Contributed.