CULTIVATION OF THE OLIVE IN NEW SOUTH WALES
By Mr. DAVID SHEPHERD.
Read before the Horticultural Improvement Society of New South Wales.
The subject for my paper is the cultivation of the olive in this colony; but before entering particularly upon that subject I think it will be interesting to you (without occupying too much time) to give a brief description and history of the olive tree itself.
The olive, botanically olea Sativa or olia Europea, is a low-branching evergreen tree, from twenty to thirty feet in height, with stiff, narrow, dark green or bluish leaves; the flowers are produced in small axillary bunches, from wood of the former year’s growth. The fruit is a berried drupe, of an oblong spheroidal form, the fleshy part hard and thick, at first of a yellowish green colour, but becoming black when ripe. The matured wood is hard and compact although rather brittle, and has the pith nearly obliterated, as is the case with box. Its colour is reddish, and it takes a fine gloss or polish, on which account the ancients carved it into statues of the gods; the moderns make it into snuff-boxes and other trinkets. The olive differs from most trees in yielding a fixed oil from the pericarp instead of the seed.
The olive is supposed to have been originally a native of Asia and grows abundantly about Aleppo and Lebanon, but it is now naturalized in Greece, Italy, Spain and the South of France, where it has been extensively, cultivated for an unknown length of time, for the oil expressed from its fruit.
The wild olive is found indigenous in Syria, Greece, and Africa on the lower slopes of the Atlas. The cultivated one grows spontaneously in Syria, and’ is easily reared on the shores of the Levant. Tuscany, the South of France, and the plains of Spain are the places of Europe in which the olive was first cultivated. The Tuscans were the first who exported olive oil largely, and thus it has obtained the name of’ Florence oil; but the purest is said to be obtained from Aix, in France. The tree attains an incredible age. Near Farni in the vale of the cascade of Marmora, is a plantation above two miles in extent of very old trees, and supposed to be the same trees mentioned by Pliny as growing there in the first century of the Christian Era.
In ancient times especially the olive was a tree held in the greatest veneration, for then the oil was employed in pouring out libations to the gods, while tho branches formed the wreaths of the victors at the olympic games. Some of the traditions say that it was brought from Egypt to Athens by Cecrops; while others affirm that Hercules introduced it to Greece on his return from his expeditions; that he planted it upon Mount Olympus, and set the first example of its use in the games. The Greeks had a pretty and instructive fable in their mythology on the origin of the olive. They said that Neptune having a dispute with Minerva as to the name of the city of Athens, it was decided by the gods that the deity who gave the best present to mankind should have the privilege in dispute. Neptune struck the shore, out of which sprang a horse; but Minerva produced an olive tree. The goddess had the triumph; for it was adjudged that peace, of which the olive is the symbol, was infinitely better than war, to which the horse was considered as belonging and typifying. Even in the sacred history the olive is frequently mentioned and invested with more honour than other trees. The Patriarch Noah had sent out a dove from the ark but she returned without any token of hope. Then “he stayed yet other seven days, and again he sent forth the dove out of the ark : and the dove came back to him in the evening, and lo, in her mouth was an olive branch plucked off : so Noah knew the waters were abated from the earth.
In Gibbon’s Decline and Fall, he quotes Pliny for the following facts. The olive in the western world followed the progress of peace, of which it was considered the symbol. Two centuries after the formation of Rome both Italy and Africa were strangers to that useful plant; it was naturalized in those countries, and at length carried into the heart of Spain and Gaul. Its usefulness, the little culture it requires, and the otherwise barren situations which it renders productive, quickly spread it over the western face of the Appenines.
According to Humboldt, the olive is cultivated with success in every part of the Old World where the mean temperature of the year is between 58 degrees and 66 degrees; the temperature of the coldest month not being under 42 degrees, nor that of summer below 71 degrees. These conditions are found in Spain, Portugal, the south of France, Italy, Turkey and Greece. The olive also flourishes on the north coast of Africa, but is not found south of the great desert. In Europe, it extends as far north as latitude 44½; in America, scarcely to latitude 34, so much greater is the severity of the winter on that side of the Atlantic. In the neighbourhood of Quito, situated under the equator, at a height of eight thousand feet above the level of the sea, where the temperature varies even less than in the island climates of the temperate zone, the olive attains the magnitude of the oak, yet never produces fruit.
Olive oil may be said to form the cream and butter of those countries in which it is grown; the tree has been celebrated in all ages as the bounteous gift of heaven and the emblem of peace and plenty. Some authors have styled it a mine upon earth.
In Italy the young olive tree bears fruit at two years old, that is in two years after it has been placed in the plantation; in six years it begins to repay the expense of cultivation if the ground is not otherwise cropped. After that period the produce is the surest source of wealth to the farmer. The age at which an olive tree ceases to be productive is not clearly ascertained. The plantation I have already mentioned as still existing near Farni, in Italy, must have attained the almost fabulous age of two thousand years, and is still in a state of productiveness. “There is” says a traveller, “an old olive tree near Gerecomio which last year yielded two hundred and forty English quarts of oil; yet its trunk is quite hollow, and its empty shell seems to have barely enough hold in the ground to secure it against mountain storms.” There is a common saying in Italy, ” that if you want to leave a lasting inheritance to your children’s children plant an olive.”
Like most other trees that have been cultivated for a length of time the olive has produced numerous varieties, different countries or even different districts cultivating their peculiar favourite. The variety longifolia and its many sub-varieties are chiefly cultivated in France and Italy. The variety latifolia and its sub-varieties are those chiefly cultivated in Spain. The fruit of the variety latifolia is nearly twice the size of the common olive of Provence and Italy, but the oil is greatly inferior.
Now if we compare the temperature of our climate with that which, according to Humboldt (and which I have already noticed), is adapted to the cultivation of the olive we shall at once perceive that we possess every advantage, as far as climate is concerned. Humboldt says that the olive is cultivated with success where the mean temperature of the year is between 58 degrees and 68 degrees; the temperature of the coldest month not being under 40 degrees, nor that of the summer below 71 degrees. The mean temperature of the year at Sydney is 65 degrees, the mean of summer 74 degrees, of winter 55 degrees, and of the hottest and coldest months respectively 75 degrees and 54 degrees. This comparison shows that our mean yearly temperature is precisely that required; the mean temperature of our coldest month is 54 degrees, or 12 degrees above the lowest in which the olive will thrive, and that of our summer 74 degrees, or 3 degrees above that required. Thus we find combined in our climate all those conditions of temperature necessary to the cultivation of the olive, which there can be no doubt were deduced from actual observation. But besides this we have a more practical proof in the fact, that the production of small quantities of oil and pickled olives of a very superior quality has already been accomplished.*
Now, although, this may be considered as only an experiment on a small scale, yet coupled as it is with the facts that small trees have produced fruit in great abundance and that little expense is incurred in the cultivation of an olive plantation, the result of this experiment is of the greatest importance to those who may be desirous of entering upon this branch of horticulture. Indeed, when the small amount of outlay necessary for their formation, and the little care and labour required in their cultivation is considered, it is a matter of surprise that plantations have not more rapidly sprung up, and that the cultivation of the olive has not received the same attention as the more expensive, and I am inclined to think less profitable, cultivation of the grape. However, a few plantations have recently been formed, and there is every reason to suppose that the proprietors will ere long be rewarded for their enterprise. But it is highly desirable that the cultivation of the olive should be more widely extended, and that all colonists who have it in their power should take up this important enterprise, which, if carried out with spirit, cannot fail to prove not only highly remuneratlve to the individuals immediately concerned, but beneficial to the colony at large. The annual cost of our imports of olive oil and pickled olives amounts to about £10,000. These imports would long before this have been rendered unnecessary had colonists been more enterprising in this matter. But besides this large saving to the colony, a great advantage would be gained in having the oil fresh and free from adulteration.
A dry, calcareous, schistous, sandy, or rocky situation is the most congenial to the growth of the olive. Where soils of this description exist with a loose and permeable sub-soil, and a sloping surface, sheltered from high winds, and a distance not too great from the sea, every natural advantage that can be wished for is obtained. The olive tree, however, will accommodate itself to soils and situations far less favourable; and there are few places in this colony within fifty miles of the sea where undulating land and a cultivable soil is to be found, in which it could not be profitably grown, but of course the more favourable the circumstances are, the less the cost and the more profitable the cultivation. Frequent complaints have been made by persons who have planted olive trees in rich alluvial soil (such for instance as the banks of the Hunter) that although their trees grow most luxuriantly they scarcely ever produce fruit. The cause of this is evidently to be attributed to the continued and too vigorous growth of the trees, induced by the great fertility of the soil. Now, as long as the trees continue in this state an abundant crop of fruit need not be expected, but I have little hesitation in saying, that when their vital energies become less vigorous, either from age or from artificial treatment, they will be found to produce large quantities of fruit. Depriving the trees of a portion of their roots is most probably the simplest and most effectual means by which to induce them to bear quickly and permanently. In the Sydney Botanic Gardens the olive planted in a poor sandy soil produces abundant crops of fruit; the same result is observable in several gardens in the vicinity of Sydney where the soil is of a strong clayey nature.
If the land selected for a plantation be of an open pliable nature trenching may be dispensed with, deep ploughing will be sufficient protection; on the other hand, if it be of a close and binding nature, it will be useless waste to plant without first trenching the whole to an uniform depth of at least two feet. In trenching this description of land where the subsoil is stiff and binding, it will be found of great advantage to future cultivation to keep the original surface soil on the top; care being taken, however, to have the whole broken up to the depth above stated. After the land has been prepared, the intended position of each tree should be staked out, so as to insure uniformity in the plantation; the proper distance from tree to tree every way is forty feet; but if it is not intended to cultivate other crops between them, in the first instance they may be planted at half that distance apart, with the intention of removing every alternate tree to a fresh plantation when their branches meet together, which, under ordinary circumstances, they will do in about fifteen years.
Planting may be proceeded with at any time between the months of April and September, but May is considered the most favourable; if the weather is moist : the plants should not be less than three years old, and if older all the better; in removing strong trees it is advisable to head them down hard, that is, cut them down to within two or three feet of the ground, otherwise their growth will be much retarded; small trees should not be cut down more than sufficient to prevent strong winds blowing them down.
The olive may be propagated by cuttings, truncheons, suckers, layers, grafts, and seeds; but it is only necessary to mention those methods which are considered the best and most suitable to the circumstances of the colony. Truncheons are large cuttings taken from the branches, of not less than two inches in diameter, and cut in lengths of four feet. They should be planted in trenches, leaving a few inches of the upper end above the surface; the soil for this purpose should be light, friable, and sandy, and so situated that it may be kept moderately moist. In three years they will be flt for the plantation; autumn and winter are the proper seasons to operate. This is undoubtedly the quickest method we have for getting trees into an advanced state, but it retards the trees which furnish the truncheons, whose supply for some time to come will be limited. In Europe the general mode of propagation is by suckers, which arise abundantly from the roots of the old trees. A number of years, however, must elapse before a supply from a similar source can be obtained in this colony. The next best and to us most available method, is grafting upon seedlings of the wild olive, which are easily obtained and are fit for grafting when the stem has attained the thickness of a man’s finger. August and September are the proper months to proceed with this operation; very good plants may be obtained from what the Italians call novoli, which are chips of the stock or main root of old trees cut into pieces of nearly the shape and size of a mushroom, care being taken that each novoli shall have a portion of bark attached. To obtain these the tree must generally be destroyed, and the plants so produced are little in advance of seedlings. Propagation by layers and small cuttings is tedious, and need only be practised where the other methods are impracticable. In England, stock of the common privet are sometimes used for grafting upon; but there the tree is only grown for curiosity or ornament, and it is not likely the practice will be found of any service where productiveness is the main consideration. Although the propagation of the olive from seed cannot be recommended as a method for stocking the plantation, yet it should not be altogether overlooked. If a few trees were occasionally raised in this way, it is very probable that a variety might be originated which would suit the situation and the soil better than its parents. But this result is by no means to be depended upon; indeed, the qualities of the seedling tree are oftener found to be inferior than superior to those of the parent. Hence this method of propagation should only be adopted as an experiment.
After the plantation has been made, it is only requisite to keep down the weeds. Should the land be required for other crops, the tillage for such will be an advantage rather than otherwise such crops as do not root deeply and are calculated not to impoverish the soil to any great extent, are the most suitable.
The proper time for gathering olives for the press is the eve of maturity, which is in April or early in May. If delayed too long the next crop is either wholly prevented or materially lessened, and the tree is only productive in the alternate years. At Aix, where the olive harvest takes place in November, it is annual. In Languedoc, Spain, and Italy, where it is delayed till December or January, it is in alternate years. The quality of the oil also depends upon the gathering of the fruit in the first stage of its maturity. The fruit should be carefully gathered by the hand, and the whole harvest completed as quickly as possible, to concoct the mucilage, and allow the water to evaporate. The fruit is spread out during two or three days in layers or beds three inches deep, it is then put under the mill (which is very simple), and care is taken not to crush the nut of the olive, as the oil of the kernel is said to injure that of the fruit and cause it to become sooner rancid. The pulp covering the stone, and containing the oil in its cells, being thus prepared is put into sacks made of coarse linen, grass, or rushes, and moderately pressed. The oil thus obtained ls, from its superior excellence, called virgin oil. The marc remaining after the first pressure is broken to pieces, moistened with water, and returned to the press; from this an oil is obtained which, though inferior to the former, is of good quality, and fit for the table. A third description of oil, valuable to the soap maker and other manufacturers, is obtained by fermenting the marc remaining from the second pressure, and again submitting it to the press.
Pickled olives are prepared by steeping the unripe fruit in an alkaline solution to extract a part of their bitter; the solution should be changed every twenty-four hours for about three weeks, after which pure water only must be used for a few days, when they are ready for preserving in salt and water, to which an aromatic is sometimes added.
The cultivation of the olive cannot be too highly recommended to the consideration of every person engaged in the cultivation of the soil. To our numerous small farmers it opens up a new field of enterprise, which, although considered in the old world one of the surest sources of wealth, requires no greater outlay of capital than that which it is in the power of all to command.
The cost of preparing and planting an acre of land with olive trees will be about thirty-five pounds. The future cultivation will cost not more than from three to four pounds a year; but by the economy of labour on a small farm, this expense may, of course, be greatly lessened. The cost of gathering the fruit and preparing the oil we have as yet (from the want of experience in the matter) no means of knowing.
In Italy and Greece, where the olive is largely cultivated, a few trees are considered sufficient for the support of a family. A full grown olive tree will produce yearly sufficient fruit to make from twenty to thirty gallons of oil, and in one instance a single tree has yielded as much as sixty gallons, but, of course, to produce such a crop this tree must have been most favourably situated as regards climate and soil.
An acre of land will contain thirty trees, and if on the average each tree produces twenty gallons of oil (in the Old World the average is greater) we shall have from this one acre six hundred gallons; which, at the moderate rate of 10s. per gallon (the present price in the Sydney market being 15s.), will be worth £300.
Now, the expense of gathering the fruit and preparing the oil must be very great indeed, not to leave a very ample profit to the cultivator.
In conclusion, I hope when the advantages to be derived from the cultivation of the olive in this colony are made more generally known, that parties who may have it in their power may be induced to give it a fair trial; and that when hereafter they are gathering their rich harvests of oil, they will acknowledge that our society has been the means of assisting in the development of some of the resources of this our beautiful land.
* A sample of colonial olive oil, grown and manufactured by Mr. Shepherd, was exhibited at the meeting. It possessed all the qualities of the finest olive oil of commerce. It was stated at the close of the reading that a sample of the same oil had been forwarded to the Paris Exhibition, and that the Judges had declared it equal to any of the olive oils grown on the shores of the Mediterranean.