LEAFLETS FOR FARMERS, NO. 30.

New Zealand Mail, Issue 1261, 30 April 1896, Page 5

LEAFLETS FOR FARMERS, NO. 30.

New Zealand Department oe Agri

culture. John I). Ritchie, Secretary. NEW COMMERCIAL CROPS FOR NEW ZEALAND. By T. W. Kir I', FLS, &e, Lond. Government Biologist. Past expciicnce has taught the lesson that it is not wise to have all our eggs in one basket, or even two. The time has come when more attention should be paid to the cultivation of auxiliary crops. This country is admirably suited to the growth of many plants yielding oils, drugs and other products of economic value, such ns opium, castor oil, pea-nut oil, linseed, &e., for which large sums are at present annually sent out of the colony. There is no rtason whatever why this money shoidd not be retained in New * Zealand. The value of the opium imported in 1894 was £4788, to which has to he added the duly of £2 per j pound, while castor oil cost the colony £8504 for hulk, on which a duty of Gd per gallon is paid, and £SOB for bottled • oil; this is charged 15 per cent, ml valorem. An illustrated article on the castor oil plant is appended. Others will be issued as opportunity offers. THE CASTOR OIL PLANT (Palma christi, Ricinus cummunis). This plant is generally believed to lie a native of India, but originated, according to A. dc Candolle, in Northeastern Africa. Now found widely spread over the warmer and more temperate regions of the earth. A very handsome and ornamental plant, glowing in tropical countries to a height of 40ft. In temperate climes it seldom reaches more than sft or Oft. There are quite a number of varieties of this species, the principal differences are in the colour of foliage only. The following is a brief description of tin typical plant: Perennial, the stems are smooth, round, with a large pith and wilh a purplish bloom in the upper portions of tho plant. Leaves, bluegreen, paler beneath, on long curved stalks, arranged alternately. Flowers, monoecious (namely, both sexes in one flower). Fruit, about lin long, blunt and deeply groove 1, armed with a “■ number of weak curved spines, as shown in the drawing. The castor oil plant was well known to the Egyptians four thousand years ago, and seeds have been found in the tombs of that date. Iris al*o mentioned by Hero lotus and Hippocrates four hundred years before the Christian era, at which time it wan extensively cultivated for the production of lampoil It is naturalised in several parts of New Zealand, and produces seed abundantly. Its cultivation has frequently been urged in past years, both in agricultural newspapers of the colon), and by witnesses appearing before Committees cf Parliament and Royal Commissions. The chief value of this plant lies in the oil which can be obtained from the seeds, nr beans as they are called. A poultice of leaves applied to the breast is said to increase the secretion of milk. The foliage is also used in the production of a particular kind of silk. Rombyx arrindi requires this plant as food.

Id has been also proved that locusts feeding on the foliage are destroyed in large numbers, while most insects shun its neighbourhood. Why not plant a lino of these shrubs round crops and orchards likely to be invaded by armies of beetles, caterpillars, die. 1 The question of growing plants poisonous or obnoxious to injurious insects has not yet received the study and attention it deserves. The possibility of combating pests by the cultivation of this class of vegetation opens a wide field for useful research. It is also stated that in Australia a belt of castor oil plant has been known to stop grass and bush fires.

As already stated, it yields a large quantity of valuable oil, which is used very extensively for medicinal purposes, as a lubricating material for all classes of machinery, and in the manufacture of soaps, pomatum, perfumed oils, for lamp oil, and for dressing leather, while the residue or marc is a valuable fertiliser, rich in nitrogen. JVleasrs Bently and Trimen give the

following account of the mode of obtaining tho oil : “ Castor oil may be obtained from the seeds in three ways : (1) By decoction, (2) hv expression, (3) by no me solvent, as alcohol. All tho oil, however, now consumed in England, India, and the United States—and, with few exceptions, in other parts of the world—is obtained by expression. All processes in which a high temperature is emuloyed are considered objectionable, from increasing the acridity of the oil. In India, in order to extract the oil, the seeds are first gently crushed between rollers, and afier the seed-coats cr hu>k j , and unsound seeds, have been removed by handpicking, the clean kernels are submitted to pressure in an hydraulic press ; and the oil thus obtained is first healed with water until the water boils, hv which the albuminous matters are separated as a scum, and the oil is then finally strained through a flannel In the north of Italy, mote especially about Verona, tho fresh seeds are alone used, and after the seeds have been broken, and their integuments very carefully removed with a winnowing machine and by the hand, the blanched

sends are put into Htnall hempen hugs, which are arranged in superposed layers in a pnweiful hydraulic press, with a sheer of iron heated to'JO'leg. between each layer, so as to enable the oil to flow readily. They are lastly submitted to pressure in a room, which in the winter is heated to a temperature of about 7Udog. The oil which first flows is of the finest quality ; hut an inferior oil is subsequently obtained by pressing the marc at somewhat higher temperature.

“lly somewhat modified processes good castor oil is also obtained in this country, and in the United Stales; but in the West Indies it is prepared by boiling the crushed seeds, after depriving them of th- ir integuments, in water, and afterwards separating the oil by skimming or straining. The oil thus extracted ig very inferior to that obtuine I by expression as before descrit <-<l.

“ Generate'huracters and Composition. —Good commercial castor oil has a viscid consistence, and a specific gravity of about O'9G. It is colourless, or pale straw-yellow, with scarcely any odour, and a mild, somewhat unpleasant taste, which is succeeded by a very slight acridity. Inferior oils have a brownish colour, a nauseous odour, and a disagreeable acrid taste. Castor oil is

especially distinguished by its ready solubility in absolute alcohol and in glacial acetic acid ; it is also soluble in about two volumes of rectified spirib It does not generally solidify until about oleg. ; and when exposed to the air in thin layers, it slowly dries up to a varnish, and hence it belongs to the class of drying oils. 11 Medical Properties and Uses Castor oil is a mild and most efficient purgative, and is well adapted for infants and young children, the puerperal state, and in irritable conditions of the alimentary canal or of the genitourinary organs It is one of the safest ami most reliable purgatives we possess for the relief of obstinate constipation, Ith s been strongly recommended by Dr Johnson as an eliminant in malignant cholera, and has the high authority of Sir Thomas Watson and numerous other practitioners in its favour.

“In India, Algeria, Ac., castor oil has been used for burning in lamps ; and the inferior qualities are also employed in India for soap-making. “ Formerly the seeds were employed as a purgative, but on account of their violent action they are not now administered. The leaves have also

been recommended in the form of a decoction or poultice, us an application to the breasts of women to increase the secretion of milk. The decoction has also been reputed to act as a lactagogue and enunenagogue when administered internally.” This plant will grow in almost any kind of soil as long as it is not waterlogged, but thrives best on light ground, and in some places docs well on almost pure sand, and in arid districts, but is cut by frosts.

The castor oil plant may he grown either as a special crop or as an auxiliary only, for the hitter purpose headlands and other such places may be utilised. There are numerous modes of planting and cultivating. If intended for a permanent crop, the land slioul ! 'no ploughed in ridges of about ] Oft in width, and the seeds sown at least Oft apart. Place two Reeds close tog.-ther, and about 2in below the surface ; this lessens the chanco of failure, and, when the plants are about Gin to lOin high pull up the weaker of the two. The advantage of having so much spaco is that the cultivator can be got through between the lines, as also a vehicle for collecting the fruit when ready. If it is intended to gather one crop only, say on the headlands for instance, it i

necessary to allow merely space sufficient to pass between the rows for the purpose of weeding and harvesting, the plants being then destroyed and used as fertilizers. Take care that the seed selected is all of one variety, plump and well matured ; if of several varieties the crop will be uneven Seed, if sown as received, will sometimes remain in the ground for a long time before germinating, several means are therefore adopted to hasten this, tho simplest being to steep the seed in hot water for a day before sowing, which should bo done about tho end of August or eaily in September, or as soon as all danger of frosts has passed. The young plants will appear in about sixteen days, and should be kept clear of weeds for a few weeks til l the foliage is well developed, after which they will be more than a match for most weeds, and need no further attention save to nip back the main stem when it is growing too rapidly, the object being to produce numerous fiuitbearing branches, and prevent the growth of long lanky stems carrying few flowering spikes. Directly the seed-capsules begin to turn brown, and show signs of bursting, they must he gathered, otherwise the seeds will be scattered over t*»e ground; therefore as soon as these

indications are observed, those spikes hearing ripening seeds are cut and thrown into a harrow or cart, the work of cutting being done by boys and girls. It is sometimes necessary to go over tho plants several times, for the seeds do not all ripen at once; this is an advantage, and enables the harvesting to be done by instalments, thus interfering less with the other work of tho farm. Tho fruit or “ pods ” are then spread out on a cloth in a sunny place, where the “ pods ” open and the seed is shed, The whole is then passed through a winnowing machine to clean the seed which is sufficiently dry to he bagged and stored in a dry place till sold to the oil-presser. The average yield is about 25 bushels (of oGlb) per acre, but 50 and even GO bushels have been grown in America, and the seeds yield from 40 to 50 per cent, of oil. The price of seed in England is said to be 12s Gd per hundredweight.

It must be borne in mind that the cultivation of castor-oil beans, or any other of these special plants mentioned, is not advocated instead of the usual farm crops, hut strictly r.s auxiliary, and, if treated in this way, it will be found that a fair margin of profit is left.

The quantity of castor-oil imported into New Zealand during 1894 for use by the general public was, in bulk, 84,858 gallons, valued at £794G—the duty on this is Gd per gallon ; in bottles, 2107 dozen pints, valued at £SGB, paying a duly of 15 per cent. ad valorem In addition to which, 6387 gallons, valued at £6lB, was imported for Government use, and on this no duty is payable. It w : ll thus he seen that there is a considerable local demand. Surely we should bo able to at least supply our colonial market. This would not only retain in the country the large sums annually spent in oil, but also find increased employment, at any rate during part of ithe year, for the boys and girls of our rural population England in 1893 imported £192,701 worth, principally from India. Large quantities are also produced in America, and in the countries along tl e Mediterranean.

It Ims often b'en said that 'his plant, is poisonous to stock, and that in Australia both horses and cattle have died as a result of eating it. Moreover, it was stated in evidence before the Victoria Royal Commission on Vegetable Products, that “ the eating of two or three of the dry seeds is deadly, inducing ‘ Asiatic cholera.' ’’ Therefore children should he warned. Stock, however, will not touch the castor oil plant unless <l l i ven by hunger. In the Analyst, 1892, it is stated that 1 percent, of castor oil seed in catth-f )od is sufficient tocause harm, ri.d ; '.!• ; death.

A( be ming on this aspect of the quesih-n, it may lie of interest to quote an article by Pol let, Liconibe, and L -scccur ( ; ‘ Jour. Pharm. cl Chim." 1893), as summ.-iiPied by Mr J. I' 1 . Bugger, ( f the United Smtes Department of Agriculture, Washington :—-

“Two pregnant cows were fed on rape cake of good quality, with no effect cn the quantity or quality of the milk, though the butter had a somewhat peculiar flavour. 2Gth May, 1893, each cow received rape cake containing castor-bean pomace. On the 27th and 28th the temperature of one cow rose to 39.6 deg C., a bloody

diarrhee i set in, and the yield of milk fell from eleven to five litres per day. This animal had recovered by the 6th June, when the adulterated cake was again given, followed by the same disturbances as before. Apparently the health of the cow was scarcely affected by the first dose of adulterated cake; but on the Ist June this cow lost her foetus of four months. A feed of adulterated cake given on the 2nd June induced fever and slight diarrhoea. By the 7th June both animals were greatly emaciated, and showed staring coats and dull eyes. The milk, after a brief period of depression, quickly increased, but did not reach the original amount. The quality continued normal, as shown by daily analyses. “ The authors call special attention to the abortive properly of castor pomace, which it is believed has not been noticed before. In addition to the above cases they knew of instances where the accidental use of c.tlce containing castor bean was followed by abortion.

“ Rape cake may bo examined for the presence of castor bean either with or without the mieioscope. A mechanical separation is effected by means of a current of water, the pulp being first washed away, and then the portions of the seed-coat of rape, while the seedcoat of the castor bean remains in the residue. In a microscopic examination the seeds of castor bean show a collection of cells containing small masses of oil and granules quite similar in form and dimension to starch grains These, however, are altered by water. The seed-coats of castor bean furnish marked characteristics. Tho outer membrane shows a network of polygonal cells, some coloured and others colourless. The inner membrane is marked by a great number of spiral ducts. A cross section of the woody membrane shows elongated pigment cells arranged in palisades, and qtiilo different from those of the rape seed. If examined chemically castor bean may he detected by tho solubility of its oil in alcohol, while rape-seed oil is quite insoluble. Rape seed oil is devoid of rotary power, while castor oil rotates yellow light toward the right. In the same way, an alcoholic extract of rape oil showed no rotary power, while a similar extract of castor cil showed a decided rotary power in tho polariscope.” May, 1895.