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Note that there is such a thing as being too popular, many plants have learned to their sorrow. For popularity, with the plant, implies a kind of attractiveness that results in the plant being eaten by some herbivorous animal. The animals can secure food in no other way, so they are not to be blamed for their marauding. But in the meantime the appeasing of their appetites spells destruction for the succulent herbs. The only resource of the plants is either to develop extraordinary capacity to thrive under adversity, as the familiar lawn grasses do; or to develop weapons of defense. These defensive measures may take the form of a tough and indigestible fiber as in the case of woody shrubs; the studding of the plant surface with spines as with the blackberry; the production of a crop of stinging hairs as with the nettle; or the secretion of oils or other chemicals that have offensive odors, or bitter, acrid, or peppery taste. In the present chapter we are concerned with a conglomerate group of plants that have resorted to the last-named expedient in the attempt to protect themselves against the unwelcome attentions of herbivorous beasts. The onion and its allies, the mints, mustard, peppers, and the others of this company, are for the most part lowly herbs or succulent bushes that have qualities of flesh that make them attractive. In self-defense they have developed added qualities, chiefly through the manufacture of essential oils, of odors or flavors that are the opposite of appealing. But as in a good many other instances, these plants by their very zeal to some extent defeat their own purposes. The unique quality of the flavors they develop, even though at first repellent to the palate, serve as a stimulus to the receptive mind of man, and urge him to develop a taste for the very things which at first seemed repellent. So it has happened that plants that seem by the very nature of their product to be denied presence on the table have come to be regarded everywhere as admirable accessories to the dietary, supplying flavors that pique the appetite and facilitate digestion. These stimulators of jaded appetites are perhaps of somewhat doubtful benefit, if we are to accept the findings of the physiologist, but they have a recognized place in the modern kitchen, and various and sundry of them are among the most important of garden vegetables. At the head of the list, doubtless, if we consider universality of vogue, are the members of the onion family, including onions proper of many varieties, and such allied species as the garlic, the leek, and the chive.


I have worked a good deal with most of these, but have found perhaps greatest interest in developing the one of them that is least generally known, the chive. The particular work of recent years with this plant has had to do with a variety which bore a flower that was originally dull crimson in color, and which, notwithstanding its disagreeable odor, appeared to combine the qualities of a border plant with those of a food plant. I secured seed of this variety of chive in Europe and raised seedlings for five years, carefully selecting in each generation the ones that most appealed. There was a considerable tendency to vary within rather narrow limits, some plants being deeper in color than others, but the divergence was not at first very marked. In the third year, however, there suddenly appeared a mutant having a blossom of bright red color instead of the usual rather dull crimson. As the chive can be multiplied indefinitely by division, this single plant might have become the progenitor of a race of red flowering chives. But I wished to see what the hereditary tendency would be, and so raised about ten thousand seedlings from the red flowering stock. Nearly all of these seedlings reverted to a pink color. There had been a faint tinge of rosy pink in the original flower, obscured by the crimson, but the new seedlings bore blossoms of a pleasing pink color, and constitute a new and highly attractive variety. While thus developing a pleasing flower and thereby adding to the attractiveness of the chive as a border plant, I paid attention also to the bulb and stalk of the plant itself as well as to the flavor. In the course of five or six generations I developed the bulb so that the average size is about twenty times that of the bulbs of the stock with which we began. Thus the new race of chives not only supplies a pink flower which has a very handsome effect when massed in contrast with the characterless flowers of its ancestor, but it is also relatively gigantic in bulb as compared with them. Thus its value as an ornamental plant and its utility as a food plant were enhanced simultaneously, and somewhat in the same proportion. These results have been attained by selective breeding, without hybridizing, in the course of a comparatively small number of generations. Development has progressed along yet another line. The one chief objectionable feature of plants of this tribe, as every one knows, is their odor. But it is well-known also that different members of the onion tribe differ greatly in this regard. In recent years the Italian and Bermuda onions, which are very mild and relatively odorless, have been introduced, and the possibility of removing from the members of the tribe their objectionable odor has come to be more generally recognized. It appears that the Italian varieties have been rendered odorless by selection from ordinary onions. Some of the improved Italian varieties are so mild in taste that they can be eaten like an apple. In experimenting with the chive I have naturally not overlooked this quality, and some of these improved varieties show a marked advance upon its ancestors in regard to odoriferousness as in regard to size and quality of bulb and beauty of flower.


My work with the other members of the family has been fairly extensive, inasmuch as I have experimented first and last with about fifty species of wild and cultivated Alliums (that being the technical name of the genus) from Europe, Asia, and America, and with various forms from Chile and from China. The onion is a very interesting plant with which to work, from the fact that it shows a good measure of responsiveness. The wild onions are exceedingly variable and the cultivated species no less so. Indeed, this might be taken almost for granted considering the long period during which the onion has been under cultivation and the large number of varieties that are in existence. In addition to the ordinary species with its well-known qualities, there are numerous handsome-flowering varieties of onion. And in the Sierras there is also a variety growing along the mountain streams which has a delicious, sweet flavor much superior to the cultivated onion. I have cultivated also an onion from China which is peculiarly sweet flavored. Some of the Chilean and Canadian leeks that I have had under cultivation differ widely in form from their Northern relatives. Some of the Chilean wild garlics have been classified as leeks by the botanists and gardeners in this vicinity; whereas the same observers classify certain of the true leeks as garlics; which suggests the divergence of form of these South American species. I am now cultivating a wild garlic from the mountains of Chile which is a wholly distinct species from the common cultivated garlic, having much larger bulbs and a taller stalk similar to that of the leek. I have in contemplation the hybridizing of this Chilean garlic plant with the familiar form of cultivated garlic. My attempts to cross the species with the onions have not met with success, although I still think it possible that this cross may be effected. My large collection of flowering Alliums from California and other countries has of course been made with the expectation of hybridizing these plants among themselves or with commoner varieties of the onion. There are interesting possibilities of development all along the line. There is a Spanish onion named the Prize-Taker because of the extraordinary size of the bulb, which sometimes attains a weight of five or six pounds. That new developments, perhaps of unexpected character, will result when the varied races from Europe, Asia, China, and Chile are blended with American stock, is quite to be expected. The onion is not very easy to hybridize because of its small flowers. But it is only necessary to use reasonable care to effect hybridization, and the results are likely to repay the effort. Indeed. whether by hybridizing or by mere selection, the onion is susceptible of great improvement along almost any line one may choose. The odor, for example, may very readily be intensified or decreased, and the size and flavor modified. On the whole I regard this as one of the most interesting vegetables with which to work. But there are many other plants prized for their flavor that also merit attention.


Prominent among these are the members of the parsley family. The common parsley and its close relative the caraway vary a good deal in flavor in individual plants grown from the same lot of seed. Only persons with a developed or specialized sense of taste are likely to notice this, however. To the person who tastes them carefully, it will be obvious that some specimens are much sweeter and better flavored than others. But as the general public is not very discriminating, it is perhaps doubtful whether it would be profitable to develop these into fixed varieties. The market for these plants is of course restricted at best. A more tangible property, and one that is likely to appeal to the user of the plant, is the shape and quality of the leaves. I have worked on the curled parsley to some extent and have found that by careful selection it can be improved greatly in a few years. The different tendencies of the leaves can be fixed quite readily in three or four generations. At one time I also developed a golden-leaved parsley, something like the golden-leaved celery. This was a plant of great promise and I expected to introduce it. But greatly to my regret, it was destroyed by millipeds just before it was ready to produce seed. I have never seen another specimen, but of course similar mutants might appear at any time, for what has happened once to a plant may happen again. Another genus of the parsley family, Liguslicum of the botanist and commonly known as lovage, is cultivated to some extent in our gardens for its aromatic seeds. There is a California species (L. Canadense) that grows along the ground, and seeds quite commonly in Northern California. The root is gathered and used by the Chinese. I have worked with this and with several allied species very extensively for a number of years. There are several native species or varieties of this family that are hard to differentiate, especially as they vary widely in different localities. All have seeds or roots with a characteristic pungent odor, but the quality of the odor varies throughout the widest range, from the most fragrant and attractive to the most disagreeable. Undoubtedly some of these wild species offer opportunities for development through cultivation and selective breeding. My own work in this regard has scarcely passed the experimental stage, however, even though it has involved a large number of species and varieties. There is opportunity for interesting and valuable work in the development of the possibilities of these bearers of flavors that appeal to the palate.


I think I have grown all the mints and pot herbs that have been under cultivation, and have found them without exception variable in quality when grown from the seed. Indeed, to the persons who taste them with care, it will appear that variation is the universal rule. Each individual plant when grown from seed has a slight difference in fragrance, and in the amount of essential oil that it contains; this oil being, of course, the source of the fragrance. It is not difficult by selection alone to obtain varieties that are of exceptionally fine fragrance and that produce a relatively large percentage of the essential oil for which the plants are usually grown. When a new variety has been obtained, it is not necessary to fix it so that it will breed exactly true from the seed; for the most of these plants can be increased by division. The mints hybridize naturally where various species grow in the same vicinity, as we have pointed out in another connection. In this way natural hybrids are sometimes produced that are so vigorous as to replace the original parent plants in the state of nature, driving them out of existence on their own ground. Among hybrid mints, whether natural or produced by hand pollenation, there will be seedlings that grow with exceptional rapidity, and that present peculiar shapes and much variation as to roughness and smoothness of leaves and form of the spikes and blossoms. In my work with all these plants, I found that quality was the one thing lacking. In any lot of seedlings grown from the pot-herbs or plants some individuals have odors that are positively disgusting, and those of some add nothing to the value of the plants, but detract when mixed with the better ones. All this is quite what might be expected when we reflect that the mints are a rather numerous family-that fact by itself proving their tendency to variation. Among the mints that I have worked on recently are species from South America that resemble the peppermint yet are in some respects distinct. An unnamed species with a tendency to cling to the ground more closely than other mints and growing so rapidly as soon to cover a large surface gives considerable promise. A species said to be hardy, sent by my collector from the mountains of Southern Chile, has somewhat the fragrance of the native peppermint. The yerba buena (Micromeria douglassi) is a common little trailing plant in the red wood forests, sometimes growing also among shrubs and along the edge of fields. It has sweet-scented, round leaves, and small, pale, insignificant, purplish flowers. This plant is fairly constant in any given locality, but specimens from different regions vary a good deal, some being rather packed growers while others run out to great lengths, with long, runner-like branches. A species of this plant of exactly the same flavor, but growing as a shrub, with brilliant fuchsia-like flowers, has been sent me from the high mountains of Chile. These evidently sprang from one original ancestor, but in our California varieties it is an insignificant trailing plant, and its relative of the Southern hemisphere is a tall shrubby plant with brilliantly colored flowers. The Chilean plant is also called yerba buena. I have attempted to cross this plant with the species from Chile, hoping thus to stimulate variation and perhaps to produce a plant of larger size, and through selection a variety of permanent value. But the flowers of the plant are quite small, making the process of cross-pollenization a rather delicate one, and my experiment has hitherto not proved successful. This, however, is doubtless due to operating on too small a scale. I have no doubt that more persistent efforts will result in hybridizing these species, notwithstanding they came from different hemispheres. Other mints with which I work are the melissa or balm, and the common garden thyme. Of the former I have raised many thousands of plants from seed, and have secured among these half a dozen in which the flavor and aroma are exceptionally pure and strong. In one of these individuals the flavor is so much more spicy than is usual that it may be said to constitute almost a new type of flavor. The experiments in improving the plant are still under way and the response made by the plant itself is prompt, giving assurance of the production of improved varieties. And scores of other plants of similar nature have given like results, but need not be specifically mentioned here. The thyme also I have grown from the seed, and have noted with this as with other members of the family a very marked tendency to variation. The most interesting variety that I have developed has been produced by selection from a seedling the leaves of which showed a beautiful white center with very uniform edges of a dark green, instead of the usual yellow and green markings. This plant, in addition to its beautiful leaf, was a more compact grower than the old variegated thyme. By selecting through successive generations I accentuated and fixed the novel leaf until it would come almost uniformly true from the seed. I offered this new ornamental variety to a dealer, but he responded that the demand for thyme was so small as not to justify its purchase. So the new plant was allowed to drop out of cultivation.


The members of this family, quite unrelated botanically to the ones we have considered, illustrate the tendencies of different races of plants to adopt similar expedients in furthering their ends. Being succulent herbs, like the parsleys and mints, the mustards have devised a similar protective measure, namely the development of essential oils that have a pungent and biting taste. But here as with the others man has cultivated a taste for what seemed a prohibitive quality, and the mustards, including not only the plants that give their name to the family, but such allies as the peppergrass, the cresses, and the horseradish, have long held a secure place in the culinary department of every household. My most extensive experiments in the cultivation of the mustard were carried out some thirty-five years ago. I worked quite largely with the Japanese and Chinese mustards, in combination with the common European mustard. These Japanese and Chinese mustards are quite distinct from our species. One kind very extensively used in China, and introduced by the Chinese in California, has the appearance of a large compact bunch of celery. The leaves are perhaps two inches in width or even more, growing so compactly that the plant is even more solid than an ordinary cabbage head, each plant weighing from two to five pounds. The leaves are blanched like celery. They have a spicy taste suggestive of mustard that is very palatable and refreshing. The plants are cooked like other garden vegetables. Another Chinese variety has greener leaves and a looser habit of growth, the plant being also considerably larger. This also is a pleasant, spicy vegetable when cooked. All the Chinese mustards run to seed quickly at the approach of warm weather, so the seed is usually sown quite early in the winter. The young plants are stimulated to rapid growth by good cultivation and fertilization, and fine large plants are ready for the market in the early spring. The plants are usually grown on raised beds and are planted about a foot apart each way. These are really remarkable vegetables that should be much more generally cultivated in the United States. In the Northern States, unless planted very early in cold frames, they run to seed without forming the large, succulent head that gives them value. Both the black and white mustard are common plants in California, the black mustard in particular being prized for culinary purposes when young and tender early in the spring and winter. The white mustard grows in enormous quantities in the fields, especially in the region about Monterey Bay, where the seed is collected by the ton, to be ground into commercial mustard. The white mustard in particular may become a pest, as it is exceedingly difficult to eradicate it, the seeds sometimes remaining in the ground several years, part of them germinating each season. About the only way to eradicate it completely from the grain and other crops, is to pull it just as it comes into bloom in successive seasons. My systematic work of selective breeding of the mustards was carried out while making similar experiments with other members of the family, including the turnips, cabbages, and radishes. I developed some superior varieties by selection, and sent the seed east to various parts of the world. But the demand was small and I presently discontinued work with these plants, although several of these and similar varieties developed are still catalogued by some American and European seedsmen. Other Crucifers that the gardener thinks of collectively, though they represent various genera, are the peppergrass and the various cresses, including the nasturtium. The common peppergrass is as variable as the lettuce. There are large numbers of plants horticulturally called cresses, with a considerable range of variation. One of the most interesting forms with which I have worked is a Chilean cress (Nasturtium Chilensi), which is as tender as the common water cress during the rainy season, and which has an astonishing ability to resist drought. This Chilean variety will withstand our summer, even if exposed to the blazing sun, and after a period of dormancy will revive and grow freely as soon as the fall and winter rains come. My experiments with it have been confined to selection for the development of varieties showing the best qualities of the plant. With the peppergrass I have worked somewhat more extensively. Some specimens of this plant have very finely dissected leaves. I have worked to develop this variety, producing leaves very similar to those of the improved varieties of parsley. The plant is rather obstinate, but I have nevertheless been successful in developing and fixing varieties having many of the desired characteristics. As the peppergrass is an annual it is of course necessary to fix the new qualities so that they will be reproduced in the seedlings. It is this rather than the mere production of the variety that offers difficulties. The familiar horseradish offers a notable contrast to the peppergrass and to most other members of the family in the matter of seed. For whereas the mustard, radish, turnip, cresses, and the rest produce seed in the greatest possible abundance, the horseradish produces no seeds at all. The horseradish does, indeed, bloom with the greatest profusion. But the blossoms prove sterile. The plant has entirely and probably forever lost the power of producing seed. I have elsewhere referred to the fact of my having created a small commotion among amateur gardeners by the joking offer of one thousand dollars an ounce for horseradish seed. Of course I knew that no horseradish seeds were to be had, yet I would gladly have given then, and I would gladly now pay, at the rate of $1,000 an ounce for horseradish seed. But there is not the remotest probability that any one will ever legitimately claim the prize. If the seed should ever be found, it will probably be dark colored, about the size of a common black mustard seed. I have received nearly or quite a thousand letters informing me that the parties writing could supply me with all the horseradish seed I could wish, inasmuch as their plants were blooming abundantly. I may add that I subsequently received large quantities of dried horseradish buds, as well as great quantities of the seeds of weeds of various sorts. I have even received what were alleged to be horseradish seeds from market gardeners. But the plants that grew from these seeds bore no resemblance to the horseradish. The interesting features of this loss of the power of seed production by plants that have for long periods been propagated by the root or from cuttings or tubers-including plants of such diverse races as the banana, the pineapple, the sugar-cane, and the potato, and nearly all plants generally cultivated in greenhouses, along with the horseradish-have elsewhere been referred to. I may add that the loss of power to produce seeds in the case of the potato is not of necessity complementary to the capacity to produce tubers. For at least once in my experience a potato plant that by rare exception produced seed developed at the same time some of the largest tubers that I have ever seen. Nevertheless there is an association between seed production and development of the root system, as we have seen illustrated. And it is not unlikely that development of the root of the horseradish may have had an influence on its seed-bearing capacity. It may be recalled that the carrot and parsnip which produce roots somewhat suggestive of that of the horseradish in shape and relative size, are biennials, and do not take on the functions of root and of seed-development in the same season. The roots are formed in the first year partly at least to supply nourishment for the development of the stem and flowers and seeds in the ensuing season. Whatever the relation between the root of the horseradish and its lack of fertility, the fact remains that the plant is propagated solely by division, and that hence there is very little opportunity for the development of new varieties or the improvement of old ones. Each horseradish root is in effect a part of an original plant now endlessly divided, and the variation in different roots depends upon conditions of cultivation or nourishment, not upon inherent differences between the different plants. It may chance some day that an exceptional horseradish plant will produce seed, just as an exceptional potato plant does from time to time. In that case there will doubtless be opportunity to improve the horseradish somewhat as I was able to improve the potato by growing plants from the seed. But until such an exceptional seed-bearer is found, we must accept the horseradish as it is, and admit our powerlessness to change it markedly.


The versatile family of Solanums, several members of which have already claimed our attention, supplies an important group of plants that are prominent among the producers of pungent and aromatic flavors. These relatives of the sunberry, tomato, potato, and eggplant, are the peppers, of which there are large numbers of cultivated varieties in different countries. The different peppers vary from the size of a barleycorn to that of a very large apple, and in color from black through scarlet, crimson, orange, and yellow to pure white. In form, some are nearly flat, others oval, yet others round or heart-shaped, or like drawn-out cylinders. Some are annuals and others perennials. As to flavor, some are sweet and palatable, while others are among the most pungent and fiery of substances that are ever purposely put into the mouth. I have worked quite extensively with the peppers, hybridizing them in various ways, and raising large numbers of the seedlings. In crossing the very small varieties with the very large ones, and the very light-colored with the very dark-colored, one produces the most unusual combinations. Even in the first generation some bushes appear having diminutive fruits and others having unusually large ones; and there is a display of different colors, including stripes, that is quite beyond prediction. Occasionally, though not often, fruit of different colors will appear on the same plant. Some hundreds of varieties of pepper have been described, but only perhaps less than a dozen are cultivated ordinarily in the gardens of temperate climates. The large sweet peppers are becoming popular. In some varieties, they are almost mild enough in quality to take the place of their relative the tomato. My own work has included the cultivation and crossing of a large number of species and varieties of pepper. At least one of these will stand a very low temperature, the plants showing no trace of injury when left where ice forms a quarter of an inch in thickness. As most of the peppers are exceedingly sensitive to frost, this hardy Chilean variety seems to offer opportunities for hybridizing experiments through which other varieties of the plant which at present are of restricted habitat may be made suitable for growth in cold climates. I have just referred to the great diversity of forms shown by such hybrids. There can be no question that selection among these and breeding through successive generations would produce almost any desired combination of qualities.

This text is from: Luther Burbank: his methods and discoveries and their practical application. Volume 7 Chapter 5