Flax: Properties and Utilization

per cent, of a fatty oil, sometimes used as a substitute or adulterant of linseed oil. The ' oilcake ' is utilised as a manure. The stems of the plant, which produce many branches, are erect and stiff, and usually grow to a height of 5 or 6 feet. The bast fibres within are not so fine as those of flax, even when the plants are grown thickly together. The leaves- are large and palmate, with from five to seven long lanceolate serrated leaflets. The male flowers have five-lobed perianths and five stamens ; they resemble those of the hop, and are borne in loose panicled inflorescences as in the latter plant. The female flowers are also very similar in structure to those of the hop, and are produced on separate plants usually of larger growth than those on which male flowers are borne. Sparsely scattered glandular hairs are met with on the leaves and stems of the plant. In the hot climates of India, Syria, and elsewhere these glands secrete a volatile oil, and a resin which has powerful narcotic properties ; in colder climates the secretion is almost devoid of poisonous qualities, although the plant pos- sesses a peculiar stupefying odour. Hemp succumbs to a moderate degree of frost, consequently when grown in this HEMP 349 country for its fibre or its fruits, the 'seed' is not sown until the beginning of May, after the disappearance of late spring frosts. When the seedlings are established they grow very rapidly, but a satisfactory crop can only be obtained on deep rich loams and alluvial soils containing a considerable amount of humus. -- Ex. 182. Examine ordinary hemp 'seed'; note its form and colour; dissect out and examine the embryo of the seed within. -- Ex. 183. Sow some hemp seeds in good garden soil, and make observa- tions on-the seedlings and full grown plants. CHAPTER XXVI. CHENOPODIAGE.^. -- I. General characters of the Order. Flowers small, regular; hypogynous, except in the genus Beta, which has epigynous flowers. Perianth green, five partite, persistent. Andrcecium of five stamens opposite to the perianth segments. Gynjecium with a one-celled ovary containing a single ovule. Fruit usually a nut, more or less enclosed by the perianth, which is membranous, fleshy or woody. Seed endospermous with a curved embryo. The plants of this Order are generally herbaceous, with simple, entire exstipulate leaves. The latter are often fleshy, and -in some genera appear covered with a whitish powder or meal. This appearance is due to short hairs which grow from the epidermis, each hair consisting of a stalk of one or two cells, terminated by a large round or star-shaped cell containing clear watery cell-sap. Most representatives of the Chenopodiaceae are met with near the sea and on the shores and marshes surrounding inland salt lakes. Many weeds belonging to the Order are specially luxuriant upon well-manured ground and on waste places where urine and fsecal matter have been deposited. The whole Order seems specially adapted to exist in soils much impregnated with common salt, nitrates of sodium and potassium, and similar compounds, and the application of common salt to the mangel and beet crop usually improves the yield. The genera belonging to it which need special mention are ' SEA-BEET 351 Chenopodium (Fat Hen or Goose-foot), Atriplex (Oraches), and Beta (Beet and Mangel). The genus Chenopodium includes a number of annual species widely distributed on waste ground, and often prevalent as weeds upon well-manured arable land. They are all very variable plants and difficult to distinguish from each other. Perhaps the commonest species is White Goose-foot or Pat Hen (C. album L.) (see p. S96). Good King Henry or All-good (C. Bonus-Henricus L.) is a perennial species sometimes used instead of spinach as a potherb, and frequently found on waste ground near villages. The genus Atripkx embraces a number of variable species, most of which somewhat resemble the Goose-foot in outward appearance. They are however monoecious (see p. 596). To the genus Beia belong wild sea-beet, and the cultivated garden and field beets. 2. Sea-Beet (Beta maritima L.) is a perennial plant common on muddy sea shores. The root is tough, moderately thick, and fleshy. The angular stems, which are many and branched, are prostrate below, but their tips curve upwards- to a height of I or 2 feet. The lower leaves are smooth, about 3 or 4 inches long, fleshy, ovate-triangular, and the blade narrowed into the broad petiole ; the upper ones smaller and lanceolate. The inflorescence, flowers, and fruit resemble those of the mangel described below. A 3. large number of cultivatedforms of beet are known, some of which are grown chiefly in gardens, and used as a vegetable for human consumption, while others, such as mangels and sugar-beet, are cultivated on the farm. They vary much in the colour and sugar content of their so-called fleshy ' roots,' and also in their resistance to frost. The shape and amount of the ' root which appears above the soil is also subject to variation. All the forms appear to be merely varieties of one species, which has been named Common Beet (Beta vulgaris L.) They differ from ; 352 CHENOPODIACEyE the wild sea-beet of our coasts {B. mariiima L.) in being biennial in habit and in having straigliter upright flowering stems, and a more well-defined uniform tap root. These cultivated forms most probably originated from a variety growing wild on the western coasts of the Mediterranean and on the Canary Isles, and known as B. vulgaris L., var. maritima Koch. Whether this plant is really distinct, or is itself a variety ol Beta maritima L., is not certain. Of \h& garden forms little can here be said. Their roots are mostly of conical or napiform shape, with deep crimson tender -- Fig. log. I. Mangel 'seed' (fruit) germinating, a Primary roots from two separate embryos. 2. True seed separated from i. 3. Longitudinal section of 2. a Root ; b cotyledons ; c hypocoty! X endosperm. A flesh, which is rich in sugar. variety known as Chard Beet (B. vulgaris L., var. Cida L.) is sometimes cultivated for the broad pale fleshy midribs of its leaves, which are cooked and eaten like sea-kale. -- 4. Mangel Wurzel or Field Beet. Mangel Wurzel is the Ger- man for 'Root of Scarcity^ by which phrase this plant was known about the time of its introduction into England as a field crop about loo years ago. This appellation appears to have arisen from the fact that it often produces a great crop when other plants fail. It MANGEL WURZEL OR FIELD BEET 353 equally deserves the name from the fact that it keeps well until late spring and early summer, when turnips and swedes have been consumed and grass and other forage crops are scarce. -- Seed and Germination. The parts known in commerce as mangel ' seeds ' are in reality fruits, two or three of which are often joined together. Each fruit contains a single albuminous seed. -- Fig. iio. 4. Seedling mangel ; 5 and 6. Older examples of the same, a Root ; i coty- ledons ;-c hypocotyl ; d first foliage-leaves of plumule. The seed is kidney- shaped, about the size of a turnip seed, with a dark smooth testa. Just within the latter lies the embryo, which is curved round the central endosperm. During germination the cotyledons absorb the endosperm and remain within the seed-coat some time after the root has made z 354 CHENOPODIACE^ its exit (3, Fig. 109). Eventually the cotyledons become free from the seed and appear above ground. The young plant possesses two narrow cotyledons, a well-marked hypocotyl, and a primary root, which is quite distinct from the latter (4, Fig. no). -- Roots and Hypocotyl. The primary root is well-developed, and secondary roots arise upon it in two longitudinal rows (6, Fig. no). The total root-system is very extensive and often penetrates to great depths in suitable soil. It is not infrequent to find drains 4 and 5 feet below the surface of the soil blocked by them. In the subsequent growth of the plant the hypocotyl becomes pulled more or less into the ground by the contraction of the roots, but the hypocotyl and root always remain more or less distinct ; the former rarely bears any adventitious roots. The 'mangel' of the farm, which is generally termed a 'root,' consists of thickened hypocotyl and true root; the relative proportion of each part is not however, the same in all varieties. In the long-red and ox-horn varieties the hypocotyl grows out of the ground; in others, such as the sugar-beet, the hypocotyl is shorter and pulled beneath the surface of the soil. A collection of leaves is seen at the apex of the mangel, and just below them Jjf: "Xi^^t^uTtoi^t are the remains of the old leaf-bases, "here cotyledon was 'present, which give to this part a rough rugged appearance (Fig. 114). A transverse section (Fig. 112) shows a series of concentric rings of firm vascular tissue alternating with rings of soft thinwalled parenchymatous bast; the cell-sap of the parenchyma, MANGEL WURZEL OR FIELD BEET 355 midway between the vascular rings, often has a crimson or yellow tint. In white-fleshed varieties the cell-sap is clear, and these parenchymatous zones are translucent when thin slices are held up to the light. The vascular rings consist of isolated strands or groups of vessels with thin-walled parenchymatous medullary rays between. It is outside the scope of the present work to deal with the complex growth in thickness of the root and hypocotyl of the mangel ; but it may be mentioned that each ring of vascular strands, with the medullary rays between and the corresponding zone of thin-walled bast, is the product of a separate cambium tissue. The individual cambium-rings arise in the pericyle of the root in rapid regular succession from the centre outwards. Sooner or later the cell-division of the inner ones ceases, but the exact length of time during which r -- Fjg. 112. t. Transverse section of mangel 'root.' 2. Longitudinal section.^ r Lateral roots ; a ring of vascular bundles ; b thin-walled parenchyma (chiefly bast-tissue). each cambium-ring remains active is not certain. In ordinary varieties usually six or seven cambium-rings complete their 3S6 CHENOPODIACE^ growth in the six months during which the mangel is growing in this country. Sometimes it is assumed that mangels with yellowish zones of parenchyma, such as is present in the Golden Tankard variety, are richer than those with quite white flesh. This, however, is an error, as very frequently white-fleshed varieties, e.g. most sugar- beets, are much richer than those with yellow or crimson flesh. There appears to be no direct connection between the colour of the ' flesh ' and sugar-content. The sugar is not evenly distributed in the tissues of the mangel, the rough ' neck ' contains much less than the rest of the ' root.' Moreover, the greatest amount of sugar is present in the cell-sap of the parenchyma lying close to the vascular ring, the cells in the middle of the zone of parenchyma between two successive rings of vascular tissue being comparatively poor in this substance. The richest mangels are therefore those in which the vascular rings are most closely placed together, and in which the parenchyma, poor in sugar, is consequently reduced to a minimum. For ' roots ' of the same diameter the best kind are those which have the greatest number of vascular rings. -- Inflorescence. During the first year the mangel usually stores up reserve-food in its hypocotyl and root, and the stem above the cotyledons remains short and bears a number of leaves in a close rosette. In the following year the terminal bud and axillary buds of this very short stem send up strong leafy angular stems which rise to a height of 3 feet or more, and these and their branches terminate in inflorescences. The inflorescence consists of an elongated axis upon which at short intervals the flowers are arranged in dense sessile clusters, each containing from two to seven flowers {A, Fig. 113) ; below each cluster is a small bract. The Flower {B, Fig. 113) is epigynous and about \ of an inch in diameter. It is bisexual and possesses a small green MANGEL WURZEL OR FIELD BEET 35;^ five-leaved perianth, the lower part of which is united with the fleshy receptacle. The androecium consists of five stamens opposite to the perianth. The ovary of the gynaecium is sunk partially in the fleshy receptacle and contains a single ovule (C, Fig. 113). The flowers of the mangel and beet are protandrous, and flowers ' set ' no fruit if specially isolated or prevented from receiving pollen from neighbouring flowers. Cross- polUnation appears to be effected by the agency of small insects and the wind. -- The Fruit. After fertilisation the fleshy receptacle and base of Fig. IX3.-.4, Portion of the inflores- ^hc perianth of each flower enlarge "ron="a',,d one closed flower of 'considerably and the separate .-,.�,� "^sfC, Vertical section of a flower, o Or.vulIe. flowers in each cluster become more zi, Cluster of two fruits developed from Or less firmlv United with flowers of B. buch clusters constitute ' commercial mangel ' seeds.' each Other (Z>, Fig. II 3). The fleshy parts with the imbedded ovaries eventually turn hard and woody, and the clusters of spurious fruits finally fall off or are thrashed off the long axis of the inflorescence and come into the market as ' seeds.' The latter are in reality collections of two or more spurious fruits. Each spurious fruit consists of the hardened receptacle and perianth with the ripened gynaecium containing a single seed, and as several of these fruits may be present in each commercial ' seed ' it will be readily understood that when one of the latter is sown several seedlings may spring from it. This peculiarity necessitates the separate hand thinning of a young crop of mangels, otherwise by growing so closely together ; 3S8 CHENOPODIACE^ the seedlings injure each other and produce deformed and small 'roots.' The true seed is very small, a fact which must be taken into consideration when sowing is contemplated as it is readily buried too deeply for proper germination. -- Varieties. Mangels may be conveniently divided according to their shape and the colour of the skin of the parts below ground. Usually the petiole and main veins of the leaves resemble the skin of the ' root ' in tint, and there is frequently a tendency for the parenchymatous zones or soft rings of the flesh to be similarly coloured. Much variation, however, exists in the colour of the skin and flesh, few crops proving quite ' true ' in these respects. The best varieties, especially the Golden Tankard, are most subject to reversion, and need constant attention on the part of the seedsman to keep the strain ' true.' A good mangel should yield a heavy crop, and the feeding quality should be as great as possible. Besides these points it is of importance to note the depth to which it grows in the soil, as the expense of lifting a deeply-seated crop may materially reduce its usefulness from the farmer's point of view. It must, however, be borne in mind that, so far as composi- tion is concerned, mangels with ' roots ' below the ground are richer in sugar and of better feeding-value than those with ' roots ' above ground. The continuation of the tap root should be single and small those with ' fanged,' thick secondary roots are more difficult to pull and clean, and generally of a coarse and fibrous nature. The ' neck ' or rough upper part of the mangel should be as small as possible, and its flesh firm and solid, with no tendency to spongi- ness in the centre. The variety should be as ' true ' as possible, so far as its shape and colour of skin is concerned, and its keeping qualities should be good. ' OX-HORN VARIETIES 359 A common fault with some strains is their inclination to ' bolt or behave as annuals, and produce an inflorescence the first season without forming a thickened ' root.' -- Long Varieties. In these the ' roots ' are three or four times as long as they are broad {A, Fig. 114), and are generally about -- Fig. 114. Chief forms of mangel 'roots.' A, Long. B, Inter- mediate. C, Tankard, i?, Globe. a half or two-thirds above the soil. These varieties give the greatest yield per acre of any kind of mangel, and are suited to deep soils, especially clays and loams. They are divided into (i) long red and (2) long yellow varieties, according as the skin is red or yellow. The long yellow kinds are somewhat superior in quality to the long red ones, but both are coarse and fibrous, and of lower feeding value than most of the va,rieties mentioned below. -- Ox-horn Varieties. These are very closely allied to the long red and long yellow varieties, but their ' roots ' assume a twisted horn-Uke shape. The part below ground does not descend below the depth of the plough furrow : they are therefore suited to shallower soils; but their irregular growth makes it 360 CHENOPODIACE^ difficult or impossible to cultivate between the rows. The quality is not good, but the yield is large. -- Intermediate or ' Gatepost ' Varieties. These have large oval roots (^, Fig. 114), somewhat intermediate between the long and globe varieties. They may be either red, yellow, or orange in colour of skin, and are suited to comparatively shallow soils. -- Tankard Varieties. The typical shape of these resembles C, Fig. 114. Two kinds are grown, namely. Golden Tankard, with orange coloured skin, and flesh with yellow zones ; and Crimson Tankard, in which the skin is crimson or rose colour, and the flesh with crimson rings. All tankard varieties have small ' roots,' and give small crops, unless grown somewhat closely in the rows. The nutritious quality of the Golden Tankard, however, sur- passes that of all other varieties of mangel. -- Globe Varieties. In these the ' roots ' are spherical or nearly so, and by far the larger part of each grows above ground {D, Fig. 1 14). They are especially suited to the light and shallower classes of soils, where they may be made to produce an excellent crop, which is readily lifted or pulled from the soil. Perhaps the commonest form is the Yellow Globe, the nutritive value of which ranks second to the Golden Tankard. Red and orange varieties are also grown. Climate and Soil. --The mangel requires a warm, dry climate, that of the south of England being much more suited to its growth than the north. The most satisfactory soils are deep clays and loams, especially for the long varieties, but lighter soils, except those of loose sandy character, produce good crops of Globes and Tankards. -- Sowing. The ' seed ' is generally sown between the middle of April and the beginning of May in drills 27 inches apart for the Globe and Tankard, and 21 to 24 inches apart for the longer varieties. It requires a somewhat high temperature to germinate satisfactorily, and it should not be drilled at a greater GLOBE VARIETIES 361 depth than | of an inch below the surface, for, although the socalled ' seed' is of some considerable size, the true seed is small, and has little power to make its way upward if buried too deeply. The amount of ' seed ' used is from 6 to 8 lbs. per acre. The young plants are subsequently 'singled' so as to leave from 10 to 14 inches between each plant in the row, the smaller distances being adapted for the long varieties, especially if smaller and relatively more nutritious 'roots' are desired. -- Yield. The average yield of ' roots' per acre is about 18 to 25 tons. -- Composition. Cane-sugar is one of the chief ingredients in the mangel. The amount varies from 3 or 4 per cent, in the large long red varieties to about 7 or 8 per cent, in the Golden Tankard and well-grown Globes. The water-content varies from 86 per cent, in the best kinds to 92 in the poorer varieties. Usually they are much superior in composition to turnips, but in damp, cold seasons large roots may be as watery as white turnips. Mangels cannot be fed to stock immediately after being removed from the land in autumn, as they contain some ingredient which produces 'scouring' in animals ; what the substance is which is responsible for this effect is not clear possibly it is ; a nitrate or oxalate. Nitrates are present in considerable abundance in autumn, but these compounds gradually diminish in amount if the mangels are kept till spring. The injurious substance, whatever it is, disappears to a large extent on keeping, the yellow-skinned varieties are generally ready to feed to stock before the red ones. The nitrogenous substances in mangels average about i'2 per cent., of which a little less than half are albuminoids. Several distinct amides are generally present, especially when the 'roots' are not ripe. The fibre averages about "9 per cent. -- 5. Sugar-Beet. The name sugar-beet is given to selected varie- ties of mangel which are specially grown for their sugar-content. -- -- ' 362 CHENOPODIACE^ The mangel first selected for improvement was a White Silesian variety (Fig. 115, A), which may be considered as the parent of all the chief varieties now grown. Sugar-beets are comparatively small, the best weighing about I J to 2^ lbs., and of conical or elongated pear shape. Unlike the ordinary mangels the sugar-beets have their thickened ' roots entirely buried in the soil, those with large ' necks ' above ground being less valuable in many ways and poorer in sugar. -- Fig. 115. Chief forms ofsugar-beet. A, White Silesian Beet or Mangel. B, Knauer's Imperial and Klein-Wanzlebener. C, Viimorin's Improved. The ' roots ' should not be ' fanged,' and in good varieties the skin is white, and the flesh firm and white, with a large number of close concentric rings of vascular bundles. Beets with upright leaves and long petioles are always less rich in sugar than those with leaves which lie close to the ground and have shorter petioles. The chief forms are exhibited in the varieties mentioned below : Viimorin's Improved. The ' root ' is conical in shape (Fig. SUGAR-BEET 363 IIS, Q> and the leaves spread out as a flattish rosette on the ground when ripe. Knauer's Imperial (Fig. 115, B).--K pear-shaped variety, usually with white flesh sometimes incUned to a roseate hue. The leaves, which have reddish veins, grow more upright than in the former variety and have somewhat crenated and puckered margins. --A Klein-Wanzlebener. variety resembling the preceding one but with more spindle-shaped root and green leaves. -- Climate and Soil. Sugar-beet thrives best in a climate possessing a warm and moderately damp summer, and having somewhat dry, hot months of August and September, during which time the sugar is stored in the root in greatest abundance. Climates such as are met with in Southern Europe are too dry and the North is too wet for satisfactory sugar production by sugar-beet. In wet climates the roots are poor in sugar. Average seasons in the British Isles are probably too damp for successful cultivation of this crop, although fair yields of roots with good sugar-content have been grown for experi- mental purposes during the last two or three somewhat dry seasons. The soil most suited to the crop is a medium loam of good depth containing a considerable proportion of lime. Heavy wet clays or very dry sandy soils are