-PRODUCINO SEEDS.

By GILBERT H. HICKS, Assistant, División of Botany, U. S. Department of Agriculture.

GENERAL REMARKS. There are over 200 species of plants whose seeds are used in making oil for illumination, medicine, food, soap, and lubricating machinery. A large proportion of these plants are natives of tropical regions, many of which will not thrive in colder climates. On the other hand, there are many plants which could be profitably grown in the United States for the oil contained in their seeds. A few such plants are now cultivated in this country, principally, however, for other pur- poses than the use of their seeds for oil, as in the well-known cases of cotton, peanuts, etc. The object of this article is to collate from reliable sources infor- mation concerning some plants which now are or which might be grown with profit for oil, thus developing a new line of agricultural activity which may in many cases prove profitable. are divided.into three classes: Fatty oils, mineral oils (such as , benzine, etc.), and volatile, or essential, oils (oil of turpen- tine, camphor, etc.). Oils of the first group are subdivided into those of vegetable and those of animal origin. Of the former, seeds furnish the main supply, although no part of the plant seems to be entirely wanting in . That found in the organs of vegetation, however, is more wax-like. The oily matter in seeds is stored up as food to be used by the young plant during the early stages of germination, before it is able to absorb food materials for itself from the earth and air. All seeds store up oil or starch for this purpose. The amount of fat in plants is said to be in nearly an inverse ratio to the amount of starch and sugar which they contain, ranging from ^7 per cent in the brazil nut to only 1 per cent in barley. Oil is obtained from seeds by first crushing and then pressing them in cloth bags, or by boiling them in water and skimming off the oil which rises to the surface, or by using some chemical solvent, such as carbon disulphide, which extracts the oil. The first method is that generally employed, although the chemical process is coming into use to a large extent. Seeds are either pressed cold in mills con- structed especially for that purpose, or heat is used to coagulate any albumen present and to render the oil more liquid. In many 185 186 YEARBOOK OF THE U. S. DEPARTMENT OF AGRICULTURE. instances both cold and warm pressure are used, but in the case of the best medicinal or table oils no heat is employed. The method of using solvents commonly yields a greater amount of oil than does pressure, but is open to objections. The crude oils obtained by pres- sure or extraction are refined by filtering and the use of chemicals. The residue of the seeds after the oil is extracted is called ''oil cake, " and is often of great value as a stock food or fertilizer. It is composed of the woody fiber and mineral matter which the seed con- tained, a small per cent of unextracted oil, and, of more value than all else, the proteid or nitrogenous constituents of the seed. This gives it especial value as food, while the high per cent of phosphoric acid and potash in addition to nitrogen makes it a most valuable fertilizer. The exportation of cotton-seed cake from the United States in 1894 was over 600,000,000 pounds, worth over $7,000,000, while that of ñaxseed amounted to nearly 128,000,000 pounds, valued at $1,700,000. Three-fourths of this material went to Great Britain.

FIG. 26.—Cotton (Gossypium barbadense). a, seed, delinted, magnified3 times; &, seed with coma attached; c, transverse section, showing the crumpled embryo filling the seed coats.

COTTON-.^

The cotton plant (various species of Gossypium) has been culti- vated from time immemorial, principally for the fiber attached to the seeds. It occurs in Asia, Africa, and tropical America, but is also grown in some parts of Europe, and, as is well known, cotton fiber forms one of the principal products of the Southern States of this country. The black seeds (fig. 26) are almost hidden by a tuft of white fiber which covers their surface. They are irregularly egg-shaped, from 6 to 9 mm. 2 long and 4 to 5 mm. broad. The thick seed coat is filled 1 See Farmers' Bulletin No. 36, U. S. Department of Agriculture. 2 For metric system, see Appendix. Consult index. OIL-PRODUCING SEEDS. 187 witli the coiled embryo, whicli is sprinkled witli brownish resin glands easily seen with the naked eye. The cells composing the embryo are filled with drops of fat and other matter. The seeds contain from 15 to 20 per cent of oil, which for hundreds of years was wasted, for the seeds proper were thrown away after stripping off the fiber. It is only within the present century that they were considered of any value except for planting. In 1826 a Virginian was led to experiment with cotton seed. He made a small machine with which he was able to express a dark- red oil that gave a fair light when burned in an ordinary lamp. In the same year, it is reported, an oil mill was constructed at Columbia, S. C, which expressed a good quality of oil from cotton seed. From this beginning there has arisen a great industry, and although cotton is still grown mainly for the fiber, the seeds are now carefully saved for the oil. Great difficulties were experienced at first in extracting all of the oil contained in the seeds, since in the process of delinting a considerable amount of fiber remained attached to the seed coat, and this greedily absorbed a large per cent of the oil. Machines have been invented, however, for removing almost all the lint as well as the hulls themselves. In Europe the seeds are first pressed cold and then warm, but in America warm pressure is generally used from the first. The crude oil is a thick fluid, of a dirty brown color. By refining it becomes straw colored or nearly colorless. Estimating 2 pounds of seed for every pound of ginned cotton, nearly 4,000,000 tons of seed were produced in the United States in 1894-95. Deducting about one-third of this, required for sowing, there would remain over 2,500,000 tons of seed. Of this amount about 1,500,000 tons were worked at the oil mills, each ton producing 45 gallons of crude cotton-seed oil and 800 pounds of cotton-seed cake. This estimate gives the immense total of 60,000,000 gallons of oil and 600,000 tons of oil cake produced in the United States in a single year. At 30 cents a gallon, this crude oil was worth $18,000,000, while the oil cake exceeds $12,000,000 in value. Of this annual pro- duction of oil about 9,000,000 gallons are used in making "compound ," while the rest is either exi3orted or mixed with drying oils or used in the manufacture of soap. Cotton-seed oil is also largely used for adulterating olive, lard, sperm, and other oils. During the last two years the exportations of cotton-seed oil from this country have been as follows: In 1892-93, 9,462,074 gallons, valued at $3,927,556; in 1893-94, 14,953,309 gallons, valued at $6,008,405. The principal European country extracting oil from cotton seed is England, the seed being obtained mainly from Egypt, from which country the imported, in 1894, 314,756 tons. Cotton-seed meal makes an excellent fertilizer. In exchanging with farmers, oil mills give 1 ton of meal for 2^ to 2^ tons of seed. The hulls are used for fuel, paper, or feeding like hay. In Russia oil cake is used to some extent for stock food. In America the cake 188 YEARBOOK OF THE U. S. DEPARTMENT OF AGRICULTURE.

(ground to meal) is used extensively and with good results as food for cattle and sheep, but has frequently been found poisonous to pigs and calves, especially when it has undergone fermentation. The meal is not infrequently used to adulterate mustard. The prin- cipal States manufacturing cotton-seed oil are Tennessee, Mississippi, Louisiana, Texas, and Arkansas. Further data concerning cotton seed may be found in Farmers' Bulletin No. 36, published by this Department.

FLAX. IsText in importance to the cotton seed for oil purposes in the United States is that of the common flax {Linum usitatissimum) ^ which, like the cotton plant, originated in the far East and has been known since the times of Moses and Homer. Flax is an annual, and at present is cultivated in nearly every country of the globe, especially in Russia and . The seeds (fig. 27) are flattened ^ h elliptical oval, pointed at the lower end, smooth, shining, and of different shades of brown. They are 3 to 4 mm. long, 2 to 3 mm. wide, and about one-half mm. thick. They are produced in a 10-seeded globular capsule, which either remains closed at ma- turity or in some forms opens suddenly, scattering the seeds. Unlike cotton, flax- seed contains beneath the shell a hard layer FIO 27 -Common flax {Linum ^f eudospcrm surrouudiug the cmbrvo. usttahssimum). a, seed, mag- . ^ o j nified 6 times ; 6, longitudinal This layer, howcvcr, is Comparatively thin, section, showing embryo im- ^^^ the oil is derived principally from the bedded m the endosperm. ^ T T IT fleshy, oval, or narrowly heart-shaped seed leaves (cotyledons) which it incloses. The outer layers of the seed coat become transformed into a mucilage when moistened with water, which gives the seeds their principal medicinal value. The seeds contain 30 to 35 per cent of oil, 20 to 28 per cent of which is obtained by pressure or extraction. Cold pressure yields 20 to 21 per cent, and the oil thus obtained is used in Russia and as a substitute for lard and in cooking. It is of a pale yellow color, and has a rather pleasant taste and smell. The warm-pressed seeds give 27 to 28 per cent of an amber-colored oil which has a stronger and somewhat acrid taste. The oil from fresh flaxseed is sticky and turbid; hence, as a rule, seeds are pressed when from 2 to 6 months old. is rather thickly fluid, rapidly absorbing oxygen, and becoming thicker, then dry and hard, when exposed to the air. It therefore belongs to the group of drying oils, of which it is the most important. It is used in large quantities for making paints, varnishes, printer's ink, and oilcloth, and to some extent for illumination and in the manufacture of soaps. OIL-PRODUCING SEEDS. 189

The cake left after the oil is removed is extensively used as a cattle food in countries where flax is grown. It contains large amounts of phosphoric acid (41.98 per cent), potash (25.24 per cent), and magne- sia (14.40 per cent), in addition to its high percentage of nitrogen; hence makes a very valuable fertilizer. In 1894 the United States exported over 127,000,000 pounds of ñaxseed cake, valued at more than 11,700,000. According to Sadtler, three-fourths of this went to Great Britain. The supply of ñaxseed comes from nearly all countries, principally from India and Russia. According to the United States consular reports, European Russia, in 1890, had 3,780,000 acres sown in flax, and the total crop of seed amounted to 1,800,000,000 pounds, or about 21,000,000 bushels. The flaxseed crop of the United States has decreased from 18,000,000 bushels, in 1891, to 7,000,000 bushels, in 1894. Our seed is exported to and Europe in considerable quantities for crushing purposes, not being considered good enough for sowing. American seed is worth about $40 a ton in , while Russian seed brings $55 to $60 a ton. There is a great difference in the amount of oil contained in flaxseed of different origins. Generally speaking, the colder the climate where flax will thrive the better quality of oil it produces, though this depends fully as much on the fertility of the soil and care taken in cultivation. The plant does best in a rather moist, warm climate, though it will stand much drier situations when raised for seed alone. In some countries flax is raised for both seed and fiber, a practice which has its advantages and is approved by the Department. How- ever, the seed is produced to some extent at the expense of the rest of the plant; hence it is claimed by eminent European authorities that the best oil seed is yielded when flax is cultivated for that pur- pose alone. Besides, when both crops are attempted, the flax is har- vested before the seed has attained the degree of ripeness which is said to be necessary to insure a full content of oil. In flax-growing centers where the processes of manufacture are carried on, the pro-* duction of fiber is much more profitable than that of the seed. In this country up to the present time flax has been grown mainly for the seed. Flax requires a deep, rich, loamy soil, well manured and thoroughly cultivated. The seed best adapted to produce a good oil crop in our country comes from Russia. The Baltic region of northern Europe also produces an excellent quality of seed. Flaxseed deteriorates rapidly from year to year, even when careful selection has been prac- ticed; hence constant attention must be paid to this subject. Well- ripened seed from the previous season is recommended for sowing. There is no doubt that in time, with proper methods of selection and cultivation, the United States, especially the northern portion. 190 YEARBOOK OF THE U. S. DEPARTMENT OF AGRICULTURE.

could produce as good seed, botli for sowing and oil, as any part of Europe. The method of cultivation of flax is somewhat different when it is raised for seed from that when fiber is desired. In the former case it is a common American practice to sow 30 to 45 pounds of seed per acre early in the spring upon turned sod of virgin soil without special fertilizing. In Europe the land is cultivated at least 8 inches deep and well fertilized with stable or liquid manure or commercial ferti- lizers. Nothing better can be used for this purpose than ñaxseed cake. The seeds should be sown with a drill, and plenty of room allowed for sun exposure. When the young plants are a couple of inches high, they should be carefully weeded, and thinned if necessary. Flax is harvested for seed when two-thirds or more of the stalks have turned yellow and the seed begins to loosen in the capsules. The harvesting should be done when the plants are free from moisture. Before thrashing, the seed is left for some time in the capsules that it may become thoroughly ripe. Various methods are employed for thrash- ing out the seed. If the seed only is desired, an ordinary thrashing machine is sufficient, but special machines are necessary when both fiber and seed are saved. From 8 to 20 bushels of flaxseed are pro- duced per acre, the latter amount being considered a large crop, secured only on the richest land with the best cultivation. The seed brings about $1 a bushel, which, added to the value of the straw when grown for fiber, makes ñax a very profitable crop. For further information concerning flax the reader is referred to the bulletins of the Department on fiber investigations.

CASTOR-OIL BEAN.

Castor oil is obtained from the seed of the castor bean {Ricinus C07nmmiis)y a member,of the family Euphorbiacese, which furnishes over 20 species of oil-producing plants, most of them indigenous to tropical countries. The castor bean is a native of India, but is culti- •vated in many parts of the globe. In Persia it furnishes the chief illuminating oil. The seed is crushed along with raw cotton wool until the oil is expressed. The cotton thus soaked is rolled up into the form of tapers, which furnish the common household illuminant. The seeds of the common large-seeded variety (fig. 28) a;re oval, smooth, and shining, of a gray ground color, irregularly marked with brown. They are 10 to 20 mm. long, 6 to 10 mm. broad, and about 6 mm. thick, slightly pointed at the upper end, which is provided with a whitish fleshy excrescence (caruncle). They are contained in a three-lobed, spiny capsule, each lobe holding one seed. When ripe, the capsules split from the bottom upward, throwing the seeds to a considerable distance. The kernel is composed of two thick, fleshy, white lobes of endosperm, which inclose a thin, leaf-like embryo. A small-seeded form is used for medicinal purposes, while the large- OIL-PßODUCING SEEDS. 191 seeded variety furiiislies an oil used for and in tlie making of soaps. Castor-oil seed is inodorous, and has at first a sweetish taste, becom- ing sharp afterwards. The shell amounts to 20 to 24 per cent of the entire seed. The kernels contain from 50 to 60 per cent of oil. It is viscid, of a pale yellow color, with a disagreeable smell and taste. is very readily soluble in alcohol, which, with its density (the greatest of the vegetable oils), renders adulteration easy of detection. It is frequently adulterated with poppy-seed oil, to which a few drops of crotón or jatropha oil is added. ^ The best kinds of castor oil come from Italy, Calcutta, and Madras, where the seed is de- prived of its shell before being pressed. This is done by women who pound the seed with wooden hammers. In America and some other countries the shells are re- moved by special machinery. The shelled seed yields from 50 to 60 per cent of oil, which is more than that yielded by almost any other plant. The oil is ob- tained by pressing twice cold and a third time warm, by boiling with water, and extraction by the agency of alcohol. It soon becomes rancid upon exposure to the air. The oil is extensively used in medicine as a purgative, also in pomades,f or illumination,

soap making, for lubricating ma- FIG. 28.—Castor-oil bean (Ricinus commums). chinery, in veterinary practice, a, frnit, magnified 1^^ times ; 6, seed, front, ' magnified 2i times ; c, back ; d, longitudinal and, in , as a condiment. section. The uses to which castor oil is devoted are constantly increasing, and a very large amount is consumed. In India castor oil is considered the best lamp oil, giving a white light, vying in brilliancy with electricity, far superior to petroleum and other illuminating oils. It burns slowly, without danger, and gives off scarcely any soot. The railway trains of India are lighted almost entirely with castor oil, and an excellent gas made from the cake is being introduced into the railway stations. The principal shipments are from India and Italy. The former country in 1894-95 exported 2,679,236 gallons. American oil is considered superior to that from India, while the Italian is said to be tho best of all, 192 YEARBOOK OF THE U. S. DEPARTMENT OF AGRICULTURE.

In Florida and other warm countries the castor bean is a perennial plant, growing from 15 to 30 feet high and as large around as a man's body. In colder climates it behaves as an annual, dying down upon the approach of winter. The seeds are produced in great abundance, and their tendency to scatter when ripe renders the plant a great pest where it grows wild. The castor bean thrives in the sandiest soil, and its culture is very simple. The seeds germinate with difficulty, owing to their thick and impervious coat; hence nearly boiling water should be poured over them before sowing, and they should remain in this for about twenty- four hours, the temperature of the water in the meantime gradually lowering to that of the atmosphere. They should be planted in hills, 2 inches deep, 8 or 10 seeds to a hill, and afterwards thinned out to 1, or at most 2, plants per hill. The rows are 5 or 6 feet apart, with the hills 2 or 3 feet distant. Between every sixth and seventh row should be left a space of about 8 feet, to permit the passage of a horse and wagon when the beans are harvested. In the South, where the castor bean grows more vigorously, the hills may be 6 or 7 feet apart. Planting should take place as early in the spring as possible, making allowance for frosts, to which the R-icinus is very susceptible. The cutworm, too, is sometimes a serious obstacle to its cultivation. The land should be kept free from weeds and the crop grown much the same as corn or beans, and on very similar soil. In harvesting, the fruiting branches should be cut off as soon as the pods begin to pop open, which is in July in the South. This process must be repeated at least once or twice a week, as fast as the seeds ripen. The fruits are then spread out to dry, either on the floor of a granary or other close room or in a " dry yard " built near the castor-bean ñelds. This yard is made by cutting away the sod, rolling the ground hard, and building a tight board fence around it to prevent loss from the beans scattering. It is better to make a tight board floor for the dry yard, which should be in a sunny place, sloping to the south. The spikes must be turned over occasionally and kept protected from moisture. After the seeds have popped out they are cleaned from the shells with a common fanning mill. Ricinus seeds should show at least 95 per cent germination and 98 per cent purity. The seeds of commerce are sometimes mixed with those of Jatropha curcas, a tropical plant belonging to the same family. Castor-oil plants have been cultivated to some extent in the United States for over twenty years. According to Simmonds, Kansas, in 1895, produced 361,385 bushels of seed from 24,145 acres, nearly 15 bushels per acre, the seed weighing 46 pounds to the bushel. In Iowa the yield is 15 to 25 bushels per acre, while in the Southern States from 35 to 40 bushels, or more, could easily be raised. The seed sells at about $1.25 per bushel. The pomace is considered OIL-PßODUCING SEEDS. 193^ valuable for fertilizing purjDoses. This plant would do well on tho- ught, sandy soil of the Gulf States, and might be made a profitable in- dustry, utilizing land that is now practically valueless.

EUROPEAN SPURGE. Spurge oil is furnished by Eupliorhia lathyris^ a herbaceous plant indigenous to southern Europe, but found in various parts of the United States, where it is usually an escape from gardens. Charles the Great recommended it to his monks for cul- tivation in their cloister gardens. . a The seeds (fig. 29) are roundish oblong, with blunt ends, reddish brown, having a roughish surface, with a prominent furrow (raphe) ex- tending the entire length of the ventral side. They are 3 to 5 mm. long by 1.5 to 3.5 mm. wide 5-.. and 4 mm. thick, with a small caruncle at the upper end like that of the castor-oil bean, to which family the plant belongs. The seeds contain 35 to 45 per cent of a very fluid, light FIG. 29.—European spurge yellow to brownish oil, which is at first mild, {Euphorbia lathyris). a, but afterwards sharp and odorous. caruncle ; ö, raphe. Mag- nified 5 times. The oil is used as a rubefacient and vesicant; also as a purgative, in doses of 10 to 20 drops. In Europe it is employed to some extent as a luminant and in the manufacture of soaps. It differs from crotón and castor oils by its utter insolubility in alcohol. Notwithstanding its valuable properties, spurge oil is employed but little, on account of its high price. There are many species of spurge growing wild throughout the United States, although the seeds of most of them are a too small to be of much eco- nomic value. Euphorbia lathy- rz5 would grow readily in most parts of the country, and its cul- o tivation might be worth a trial. SUNFLOWER. The common sunflower {Hel- ianthus annuus) is an annual, FIG. 30.—Sunflower (Helianthus annuus). a, akene, 5 to 15 feet high, and indig- magnified 2i times; 6, longitudinal section; c, enous to America. In 1569 it transverse section in outline. was introduced into Europe, and is now extensively cultivated there, particularly in Russia, where it has been grown for over fifty years, principally for the oil contained in its seed-like fruits (akènes). It grows wild throughout the United States. The akènes (fig. 30) vary a good deal in size, some from southern California being but 5 mm. long and one-half as 2 A 95 7 194 YEARBOOK OF THE U. S. BEPAETMEÎÎT OF AGKICüLTüßE. wide, wMle in cultivation they average from 8 to 10 mm. long by 6 to 8 mm. wide and 3 to 4 mm. thick. They are obversely egg-shaped, compressed, usually of a gray color striped with black, and in some cases entirely white or black. The gray and striped seeds are pre- ferred by some growers, the smaller ones being said to contain the most oil. The seeds, after the shells are removed, contain 34 per cent of oil, of which 28 to 30 per cent is extracted by cold and warm pressure. ' is clear, light yellow, nearly odorless^ and of a peculiar, pleasant and mild taste. This oil is said to be superior to both and for table purposes, and is used in making soap, , and for lighting. The residue, after extracting the oil, is made into oil cake for feeding cattle. The export of this cake forms one of the principal industries of Bussia. In Russia the larger seeds are sold in immense quantities to the common people, who eat them much as we do peanuts. The stalks furnish a valuable potash fertilizer, while the green leaves are dried, pulverized, and mixed with meal as food for cows. Sheep, pigs, and especially poultry, fatten rapidly upon the seeds, preferring them to other kinds of food. The stalk is said to produce an excellent fiber by treating it the same as flax. It is said, also, that much of the Chinese silk goods contains sunflower fiber. Five or six cords of stalks are produced per acre, which are sometimes used for fuel, while the flowers furnish a yellow dye. The foregoing remarks apply to the culture and the use of the sun- flower in Europe. In this country attempts at its culture have been made by a few experiment stations and private individuals. Accord- ing to a newspaper report, a farmer in South Dakota planted, in 1895, 100 acres to Russian sunflowers. The main drawbacks thus far to sunflower raising in America are the lack of machinery and the want of a good home market for the oil. It is likely, however, that these difficulties will be ultimately overcome. In Europe old mortar broken up is said to make an excellent fer- tilizer for sunflowers. Fresh manure, especially horse manure, causes an undue development of the stalks and leaves at the expense of the seeds. It is recommended that old manure be applied to the field in the fall, the seed being sown as early as possible in the following spring. The seeds should be planted about 1 inch deep, 6 inches apart, 18 inches between the rows. When the plants are 8 or 10 inches high, thin them out to 30 inches apart and hill them slightly. Keep them entirely free from weeds. When about 3 feet high, the runners should be cut off, leaving one main stem with four or five flower heads. 'No further care is needed until harvesting. The soil should be rich, dark mold, with as little shade as possible, since the sunflower^ as its name indicates, requires plenty of sun. OIL-PRODUCING SEEDS. 195

About 6 pounds of seed per acre is recommended, and it may be sown in drills. The heads must be harvested promptly as soon as ripe, as birds are very fond of the seeds. If the acreage is small, the heads may be taken off one by one as fast as they ripen. Care must be exercised to dry them as rapidly as possible to prevent molding. In Europe the average yield per acre is 2,000 pounds of seed, giving 250 pounds of oil. In America the seed sells from 1^ to 2^ cents per pound. In thrashing the heads it is best to pile them in a row on the barn floor, placing the seeds uppermost. Continue in this manner until the pile is about 2 feet high, placing the last row with the seeds down to prevent breaking them with the flail, this being used in thrashing. The seeds are then thoroughly dried in the sun and run through a cleaning mill. They are next separated by means of screens into two sizes—one large, the other small. Sunflower seed may be purchased from any prominent seedsman. It.should show a germinating per cent of 90 and a purity per cent of 99. The price of labor in Kussia where sunflower raising is such an industry is so much smaller than in this country that the profit in the business for American farmers is a somewhat uncertain factor at present. MADIA SATIVA.

This plant, belonging to the sunflower family, is a native of Chile, where it has been cultivated a long time for oil. It is an annual, growing from 1 to 3 feet FIG. 3i.-Madia (MO- higli, with a large mass of sticky, iU-smeUing foliage ^¿a^a s ^¿' and yellow flowers. The akènes (fig. 31) are 6 to 7 mm, long, 2 to 2.5 mm. wide, and 1 to 1.5 mm. thick, slightly bow shaped, broadest at the upper end, gray in color, the surface being ridged with fine, longitudinal lines. The seeds contain about 32 per cent of a rich , oil, which is used for food, making soap, and illumination, and is said to be as good for cooking purposes as olive oil, which it supersedes in some countries. The fact that it does not readily congeal makes madia oil valuable for lubricating machinery. Madia has been cultivated to some extent in and Germany and grows wild very abundantly in California. It flourishes on almost any kind of soil, and as it requires but three months to ripen may be sown late in the spring if desired. The cul- tivation of madia is very simple, although, as in the case of other crops, it responds to good soil and tillage. In France it is sown broad- cast from the middle of April to the middle of May on well-prepared mellow soil, about 20 pounds of seed per acre. The seed comes up in ten to twelve days, and as soon as the plants have made a stand they are thinned out. At the first hoeing they are again thinned to 1 foot 196 YEAKBOOK OF THE U. S. DEPARTMENT OF AGRICULTURE. apart. The crop is harvested within ninety to one hundred days after sowing. Harvesting should take place as soon as the seeds are well ''set," without waiting for them to become thoroughly ripe, as they shell out easily; moreover, they finish ripening after the plants are cut. Har- vesting is done in France with a sickle. It is claimed that if properly cultivated and gathered madia will yield from 1,200 to 1,400 pounds of seed per acre, making over 20 gallons of oil. The plants should be thoroughly dried before thrashing. Madia could be successfully grown in California and other sections of the United States. The principal drawbacks are the disagreeable odor exhaled by the flowers, the greasy nature of the foliage, and the irregular ripening of the seeds.

NIGER SEED. Niger-seed oil is made from Ouizotia oleífera, another member of the sunflower family and a native of Abyssinia. It is an annual, fur- nishing the common lamp oil of upper India, Avhere it is cultivated. The akènes are similar to those of madia, but smaller and darker. They are used in this country to some extent as bird food. They yield 35 to 40 per cent of a brownish oil, which becomes pale yellow after refining. It has a slightly aromatic odor resembling thyme. The cold-pressure oil is used for food, and that obtained by warm pressure for making soap, but it can not be used alone for this purpose, since it renders soap brittle. In India the seed is sown in July or August, after the rainy season, and is treated like a wheat crop, no weeding or manuring being required. It yields about 2 bushels per acre, and is exported to Lon- don and Hamburg principally. This plant could undoubtedly be successfully cultivated in the warmer portions of the United States.

PEANUT.^ The earthnut, groundnut, goober, pindar, or peanut [Arachis hypo- gœa), as it is variously called, is a low, somewhat creeping annual belonging to the bean family. It is a native of the tropics, but has been for a long time cultivated very extensively in Africa, India, the West Indies, and warmer portions of America. Only the lowest flowers bear fruit, and after blooming these flowers lengthen their stems, which penetrate the ground several inches, where the fruit ripens. The fruit (fig. 32) is 2 to 3 cm. long and 1 to 1.5 cm. thick, with a furrowed, yellowish pod, which contains from 1 to 4 seeds, 1 or 2 being the common number. In addition to their general use for food

^ The peanut is more fully treated of in Farmers' Bulletin No. 25, U. S. Depart- ment of Agriculture. OIL-PRODUCING SEEDS. 197 and confectionery, the seeds furnish 38 to 50 per cent of oil. The first cold pressing yields an almost colorless oil, of pleasant taste and smell, which is excellent for table nse. After the first pressing the seeds are sprinkled with water and pressed again, cold, to obtain the oil, which is also used to some extent for food purjjoses, but mostly for illumination. The third oil is extracted by warm pressure, and is in great demand for making various kinds of soaps. The cake is considered an excellent food for stock. The peanuts grown in trop- ical countries are said to yield a much greater per cent of oil than those raised in temperate regions. In the United States peanuts are usually planted after corn, 2 bushels of seed being used to the acre. Planting takes place as soon as all danger from frosts is past. A warm, sandy loam containing some lime is the best soil for peanuts. The crop is from 80 to 120 bushels an acre. The oil is chiefly extracted at Marseilles, France, which annually imports 137,000,000 pounds of peanuts. In this coun- try peanuts are principally used for eating, 3,250,000 bushels being a h o

FIG. 32.—Peanut (Avachis hypogœa). a, fruit; 5, seed; c, same with coat removed, showing the fleshy cotyledons. All magnified li times. consumed annually for that purpose. In other countries they are not esteemed so highly for food, hence nearly all the foreign product is used for oil. At present the conditions in the United States are not favorable for making oil from peanuts, although it has lately been attempted on a small scale. It is quite likely, however, that peanut- oil manufacture will become an important industry in America in the future. SESAME. The oil of benne, or , as it is more frequently called, comes from the seeds of Sesamum indicum and Ä orientale, two almost, if not quite, identical plants belonging to the Pedaliacese. They are indigenous to the East Indies, but are extensively cultivated in and other subtropical countries. Within a comparatively few years their culture has been undertaken by Germany, France, Austria, and England. Sesamum orientale has been cultivated in Asia since the earliest times. The Babylonians and ancient Egyptians used the seeds for food, and the Egyptian women prepared a cosmetic from them. The plants are hairy, sticky annuals, about 3 feet high, and pro- duce an abundance of small, flat, pear-shaped seeds (fig. 33), those of 198 YEARBOOK OF THE U. S. DEPÀKT3ÎENT OF AGRICULTURE.

Sesamum indicum being y ello wish white, while the seeds of S. orien- tale are black. Sesame seeds are very rich in oil, yielding from 50 to 56 per cent in the black-seeded varieties, and 47 to 52 per cent in the white-seeded varieties. The former are also said by some to produce a better oil than the latter, while others claim the reverse is true. The seeds are also used in confectionery and for making soups. The oil is clear, of a pale straw color, sweet, and nearly tasteless. It is obtained by three pressures, twice cold and the last time warm. The first pressure gives the best oil for food purposes. Sesame oil is frequently used to adulterate almond oil. It is also used for making soaps, for illumination, in perfumery manufacture, and for the toilet The seeds of commerce come chiefly from the East Indies and the Levant, the oil being pressed at Marseilles and Trieste. The best seed is shipped from Jappa to Mar- seilles, where the oil brings the FIG . 33.—Sesame {Sesamum indicum). a, seed, highest price of a,ny of the many magnified 10 times ; b, transverse section. kinds in the Marseilles market. The leaves of the sesame plant are considered of medicinal value, from the mucilaginous matter which they contain. Sesame ripens its seeds in most of the Middle States, and might be profitably cultivated in the South. The negroes near Charleston, S. C, are said to have grown sesame in a small way for two hundred years. They plant it in April and harvest the seeds early in Octo- ber. The seed used for planting should show a purity of 98 per cent and germination of 90 per cent.

HEMP. Hempseed oil comes from an annual plant of the nettle family {Cannabis sativa)^ which is indigenous in central Asia and the East Indies. It is cultivated in India, Persia, China, North America, Germany, and, more than anywhere else, in Russia. It grows from 4 to 8 feet high in waste and cultivated ground. The odor of the fresh leaves sometimes produces headaches, while the celebrated narcotic, hashish, is prepared from a gelatinous resin contained in the leaves and stems. The latter also furnish the well-known fiber used for cloth and cordage. The male and female flowers are borne on different plants. The nut-like fruits (fig. 34), commonly called seeds, are used in great quantities as bird food. They are nearly egg-shaped in outline, flattened at the margins. Color, dark gray, with fine, net-like, w^hitish markings on the smooth and shiny surface. Each fruit is completely filled with the seed proper, which is of the same shape and about 4 mm. OIL-PRODUCING SEEDS. 199 long bj^ 3 mm. wide and 2 to 3 mm. thick. The seeds contain no endosperm, but are filled with a whitish embryo which yields 30 to 35 per cent of a peculiar-smelling, mild-tasting oil, greenish yellow when freshly pressed, becoming brownish yellow with age. Hempseed oil is used to a considerable extent in the preparation of paints and var- nishes, although it does not dry as readily as linseed oil. In Europe it enters largely into the comx30sition of soft soaps. Sometimes it is used in the Old World as an illuminant and, rarely, for food. Hemp will thrive in most parts of the United States, and is said to produce from 20 to 40 bushels of seed to the acre, worth about $2.50 per 100 pounds. With extra good care and soil the yield may reach 50 to 60 bushels. The seed should be planted in drills, early in April in the South, two weeks later in the North. The young plants are thinned out when a foot high, and must be kept free from weeds. The male plants should be pulled as soon as they have shed their pollen, so as to allow the seed-producing ^ plants plenty of room and all of ^_ h the available soil food. Hemp should be harvested promptly as soon as the seed begins to drop, which always takes place after a sharp frost, if not before. The seeds scatter easily ; hence hemp should be cut early in the morning when the ^i^. 34.-Heinp {CannaUs sativa), a, fruit; 6, _, , _ , transverse section of seed. Magnified 6 times. dew IS on, and great care exer- cised to prevent waste. When cut, hemp should be set up in loose shocks to dry, a sheet being placed under each one, and some protec- tion afforded from birds, as they are fonder of this seed than almost any other. Drying is completed by spreading the plants out on a tight barn floor, where they are thrashed by hand. Hempseed, nothwithstanding its oily content, loses its germina- tive power quickly, usually by the end of one year; hence only fresh seed should be sown. Neither cracked nor dull-looking seed will ger- minate well. Hemp culture in America is mostly confined to Ken- tucky and Missouri, principally the former State. The value of hemp for fiber, birdseed, and oil would seem to make its cultivation a very profitable one. RAPE. , or colza, oil is obtained from the seeds of different vari- eties of the genus Brassica, rape {Brassica napus) in particular. In Europe the term rapeseed oil is sometimes applied to the product of rape alone, colza being restricted to the oil obtained from the ruta-baga, or Swedish turnip {B. campestris), while "Rübsen" oil is furnished by the common turnip (B, rapa). There is great confusion among authors in the use both of the common names of 200 YEARBOOK OF THE U, S. DEPARTMENT OP AGRICULTURE. the oils and the scientific names of the varieties of Brassica which produce them. Since the characteristics of the different varieties of rapeseed oil, as well as the methods of culture of the plants themselves, are practi- cally the same, we shall include them all under the head of rape. According to Blomeyer, rape originated on the coasts of Holland and England. It has been cultivated extensively in Europe since the middle of the sixteenth century. In France rape constitutes seven- tenths of the acreage of oil seeds in cultivation, though this has decreased somewhat in recent years, owing to the more extensive use of mineral oils. In Germany there were 445,000 acres planted to the different varieties of Brassica in 1882, the value of the crop of rape- seed being over $10,000,000. Besides this, large amounts of rapeseed were imported, so that the value of rapeseed oil from Germany alone was $12,000,000 to $14,000,000, while in addition over $4,000,000 worth of rapeseed oil cake was produced. The total consumption of rape and colza oil in Europe is estimated at nearly 330,000,000 pounds per annum, valued at over $43,000,000. India annually exports from 2,500,000 to 4,000,000 hundred b weight of rapeseed. A large part of this naturally goes to Great Britain, which imports about 880,000 pounds per year. The seeds of all the varieties of Brassica are spherical and not easily distinguishable from one another. Those of B, napus FIG. 35.-Rape {Brassicanapus). a, seed ; 6, trans- /ßg^ 35) ^r^ mOStly bluish-black, verse section. Magnified 14 times. V^ , . _.,.,_ ' B, campestris reddish-brown, B, rapa almost black. As a rule the seeds of B, campestris are somewhat larger than those of the other varieties, whose seeds average about 2 mm. in diameter. Brassica seeds are more or less pitted when seen under a lens. The seeds of rape contain from 33 to 43 per cent of oil, which when crude is a dark yellow brown and used for lubricating. Refined and freed from albumen and mucilage the oil becomes bright yellow. Rape oil is extensively used for lamps, lubricating machin- ery, and for adulterating both almond and olive oils. It is frequently adulterated with poppy seed, camelina, flaxseed, mustard, whale and fish oils, and with . The refuse cake is a well-known and valu- able cattle food. Brassica campestris (colza) is said to yield one-third more oil than rape. Both rape and colza thrive best on rich, deep soil, especially after barley, wheat, and clover. The soil must be well drained. In a very light or very stiff soil heavy manuring is required, rapeseed cake being excellent for this purpose. Rich liquid manure, such as night soil mixed with water and drainings from barnyards, produces OIL-PRODUCIKG SEEDS. 201 extremely luxuriant plants. Under such conditions in Germany rape sometimes grows 6 feet high, yielding 1,200 to 1,500 pods to each plant, with 40 to 50 seeds in a pod. But such crops as this require the utmost fertility and care. No plant responds more noticeably to manuring and cultivation than rape, the difference often being more than 50 per cent over a neglected crop. The different varieties of rape fall under two heads, summer rape and winter rape. The former comes from seed sown early in the spring and maturing in the same season, the plant being an annual. Winter rape is a biennial, or, more properly, a winter annual, and is considered a better oil plant. In Germany winter rape ripens in three hundred to three hundred and fifty days; summer rape in one hundred and forty to one hundred and eighty days. Summer rape is said to be a more uncertain crop than winter rape, being better adapted to a light soil. The yield is 33 to 50 per cent less than from winter rape. Rape will not withstand severe winters well unless covered with snow; hence, although bottom lands are considered excellent for summer varieties, they are not recommended for winter rape on account of their liability to frosts. When planted for seed purposes, rape should be sown with a drill or a seeding machine. The seed should show a germinating per cent of 95 and a purity percent of 99. In Germany different methods are used for sowing rape. In some cases it is drilled in rows 1^ to 2 feet apart, with the seed 4 to 5 inches apart in the row. Four to 7 pounds of seed is used per acre, winter rape being sown the last of July or before the middle of August, summer rape in May or as soon as danger of spring frosts is past. The land should be prepared thoroughly, and it is recommended that the seed be ^ut in the fresh furrow the same day the land is worked. Sow one-half to 1 inch deep, rolling or dragging the land afterwards. About the middle of September the ground is cultivated, and in October hilled once or twice with a hill plow. If seeded too thick, it must be thinned as soon as the seedlings are well established in the soil, and again in the spring. Another common practice in cultivating rape for seed is to sow in large beds and afterwards transplant. The seed bed may be prepared by digging trenches in well-manured, loamy soil. As soon as the plants have five or six leaves they are thinned to 4 or 5 inches apart. One acre of seed bed will furnish enough plants for 10 acres or more in the field. As in the other method, the seed is not sown until July or August, to prevent the plants from running to seed the same year. Transplanting takes place in September or October, great care being exercised not to injure the roots. The plants should be care- fully lifted out of the soil with a fork, the earth still clinging to their roots, and placed in flat baskets, tops upward. In planting, the holes should be made with a large dibble or narrow hoe. The earth is 2 A 95 -7* 202 YEARBOOK OF THE U. S. DEPARTMENT OF AGRICULTURE. drawn up to the plant with another hoe, and as the holes are filled the planter firms the earth with his foot as he walks along. Two men with hoes and one boy to insert the plants would cover a large space in a short time. In the spring the weeds must be carefully cleaned out, and if the ground has been oversoaked during the win- ter, the rape should be hilled a second time. Rape ripens its seed very unevenly, the lower pods beginning to burst before those at the top are filled. The crop should be harvested at the end of June or the 1st of July, when the pods begin to turn brown and the plants are fully mature, so as to prevent a waste of the seed, which rattles out easily. It should be cut in the morning when the dew is on. In Europe the cutting is regularly done with a sickle, and continued daily as the pods turn brown. The plants are laid on the ground in piles, with the pod ends toward the center. These piles remain in the field several days, until sufficiently dry, when they are hauled into the barn upon sheets spread in the wagon. To prevent a waste of seed in loading, a large sheet is also spread on the ground by the side of the rows as they are lifted into the wagon. Rape should be harvested in a dry season, else much of the seed will be lost, some loss being sustained with the best of care. If the weather is favorable, the seed may be thrashed in the field upon a large sheet of canvas. It should be spread out about 4 inches deep on the floor of the granary and turned over daily for a week or so, to prevent heating and molding. The yield varies greatly, being in Germany from 1,800 to 2,600 pounds per acre. One bushel of seed yields 16.4 to 21 pounds of oil and 29.5 to 36.4 pounds of oil cake. In addition to this, 225 pounds of straw and pods are reckoned to every hundredweight of seed. In Europe the straw and pods are mixed with potatoes and used for fodder. In this country some varieties of rape, especially that known as the Dwarf Essex, are being cultivated to a slight extent for forage, but so far as we know rape has not yet been grown in the United States for seed. Rapeseed could be successfully raised in any of the Northern or Western States; probably in the South also. The only question is whether the industry would be a profitable one on account of the immense extent to which it is carried on in Europe, where labor is cheaper. Considering the great demand for rapeseed as bird food, as v/ell as for oil, and the good price it brings, its culture seems well worthy of a trial. It must be borne in mind that the varieties of rape useful as forage are of no value for seed; hence it must be cultivated solely for one purpose or the other. The seed of the wild mustard, or charlock {Brassica sinapistrum), a serious weed in some parts of the West, yields an oil similar to that of rapeseed. The same is true of false flax {Camelina sativa)^ which OIL-PKODUCING SEEDS. 203 is often found as a weed in flax fields. Other members of tbe mustard family, as black mustard {Brassica nigra), white mustard {Sinapis alba), radish {Baphanus sativus), etc., furnish oil-producing seeds and are cultivated to some extent for this product.

POPPY. Poppy-seed oil is furnished by the seeds of the opium poppy {Papa- ver somniferum), an annual plant, originating in Asia, where it is cultivated very extensively, principally for the juice derived from its capsules, but also for its seed. The seeds (fig. 36) are less than a millimeter in length, kidney-shaped, with the surface regularly pitted, giving them a beautiful appearance under a lens. There is a black- seeded and a white-seeded variety under cultivation. Fifty per cent of oil is obtained from the seeds by warm and 30 per cent by cold pressure. It is pale yellow, with a bland and slightly sweetish taste, totally destitute of narcotic properties. Poppy-seed oil is used for salads, paints, soaps, illumination, and to adulterate olive and almond oils. It is worth 35 cents a pound in this country, the white-seeded vari- ety yielding the best oil. The plant thrives in a dry, warm climate, requiring no more care than corn. It does well in almost any dry soil if it is not too heavy, preferring a light, friable clay containing some FIG. ^.—Opium poppy {Papaver somniferum). a, seed ; 5, longitudinal section. Magnified 35 lime. Well-rotted stable manure times. should be applied, but if the soil is rather light, soluble phosphates will be found to greatly increase the seed crop. Sowing should take place early in the spring, since the poppy requires about five months to mature its seed. The seed germinates slowly, often requiring four weeks if the weather is cold, while in warm weather two we*s is sufficient. The seed should be drilled in rows, 1^0 18 inches apart, fresh seed saved from large, plump cap- sules being used. Under no circumstances should the black an4 white varieties be sown together, as this lessens the value of the crop. On soil which is medium heavy scarcely any covering is needed, and on the lightest soils the seeds should not be sown more than one-half inch deep. After a good stand is secured, the plants should be thinned out to 4 or 6 inches, or even more. They are then treated the same as any hoed crop. The poppy is remarkably free from insect and fungous attacks; hence under ordinarily favorable conditions the seed crop is certain. 204 YEARBOOK OF THE U. S. DEPARTMENT OF AGRICULTURE.

Harvesting should take place when the pods become leathery and the seeds begin to rattle in them. Dry weather must be chosen for this purpose, and under no circumstances should the seeds be allowed to get wet. The workman walks along the rows and shakes the ripe seeds into a bag w^hich he carries. This is repeated every six or eight days until the entire crop is harvested. Then the plants are cut, bound in loose shocks, and allowed to dry. In Europe they are used for straw and fertilizer, but are not suitable for fodder. The seeds are carefully dried and are then ready for market. An average crop is said to be from 1,000 to 1,200 pounds per acre, yielding about one- half this weight of oil. In addition to various portions of Asia, where poppy growing is the principal industry, a considerable amount of seed is raised in north- western France, and some in Germany. It would probably do well in the southern and southwestern parts of this country. The Mexican poppy {Argemone mexicana)^ which is widely distrib- uted throughout the globe, and an abundant weed in California and other sections of the United States, is grown for oil in some countries.

OTHER OIL-PRODUCING SEEDS. Among other plants whose seeds furnish oil, the following may be .mentioned as growing in the United States, either wild or under cul- tivation: Melon, soja bean, maize, tobacco, fennel, dill, anise, parsley, caraway, coriander, celery, lovage, and wormseed {Chenopodium antliélminticum). Oils from some of these seeds are used in the prep- aration of medicines, and bring a good price. Whether their cultiva- tion would prove profitable at the present time can be decided only by experiment. The following quotations, from a recent number of the Bulletin of Pharmacy, will afford an idea of the relative value of some of the oils mentioned in this article: Oil: Price. Anise perpound__ $3.35 Caraway.. _do 1.80 Castor - _ _ _ - .per gallon. _ 1.95 Castor (macliine) do 1.10 Coriander per ounce.. 1.25 Cotton-seed _ per gallon in barrels. _ . 43 Crotón per pound._ 1.20 Fennel do 1.65 Linseed (boiled) per gallon in barrels. _ . 48 Linseed (raw; do .45 Poppy _ _ per pound. _ . 35