OTHER USEFUL PLANTS WHICH WILL REPAY EXPERIMENT
TRANSFORMATIONS AND IMPROVEMENTS WAITING TO BE MADE
A story is told that, if true, gives a Mikado of Japan an important place among plant developers. The Mikado, so the story runs, was riding about the country-as was once the custom-to inspect the crops, and he espied a bunch of rice which seemed to be earlier and more productive than others in the same field. Evidently aware of one of the fundamental principles of plant breeding, the Mikado directed that the seed from this hill of rice should be carefully preserved and sown by itself the next season. From this seed, if we are to believe the legend, a superior new variety of rice was produced in Japan. Whatever the authenticity of the story, the fact that it is told gives evidence that some of the fundamental principles of improvement of plants by selection are widely recognized in the land of the Mikado. But this, indeed, is a proposition that scarcely needs demonstrating, considering the curious variety of flowers and fruits that have been developed there. That the revered name of the Mikado should be associated in popular legend with the perfecting of the rice, is to be interpreted, I suppose, as an evidence of the importance of this grain to the people of Japan, rather than in any literal sense. Rice is to the Oriental people what wheat is to the people of the western world, and it is natural that folklore should associate the perfecting of this most important of foodstuffs with the most sacred office of the ruler who is regarded as the Father of his people.
RICE AND ITS IMPROVEMENT
Mention of the perfecting of special varieties of rice implies the existence of different varieties of this grain. In point of fact, rice is a variable plant, and one that is therefore susceptible of great improvement. There are many varieties of rice grown in the Orient. There is, for example, a variety that has a very pleasant aroma when cooked. There are varieties that grow on the upland, the culture of which is similar to that of wheat or barley; notwithstanding the fact that rice is usually thought of as a marsh plant. These have recently been introduced into the cotton regions of the south, and I am told that in some regions they are supplanting the cotton crop. Also an attempt is being made to grow the upland rice in certain sections of northern California, and with a large measure of success. In point of fact, some botanists have classified no fewer than six species of rice, and there are hundreds of varieties, variation seeming to be no more unusual than with wheat, oats, or barley. It is only the relative unfamiliarity with rice of the western world that has led to the supposition that one kind of rice is like another. Our estimate of the grain is somewhat analogous to our estimate of the Oriental peoples. The casual western observer thinks that all Japanese and all Chinamen look a good deal alike; but to the practiced eye there is nearly as great diversity among them as among European races. The upland rices show their derivation by requiring somewhat moist soil, and they are not grown to advantage in California; at least they have not been extensively cultivated hitherto except in the moist retentive soils of the Sacramento Valley, and to a certain extent in the Coachella Valley. In the former region, however, the reports as to the growth of the upland rice are exceedingly favorable. I have tested different kinds of rice here on several occasions, but the results were not such as to induce me to continue its culture, the condition not being favorable. But the fact that varieties of rice have been developed that grow on the upland gives assurance that further development may be possible in the direction of adapting the plant to general cultivation on lands suitable for growing of other cereals, as already demonstrated in the South. Doubtless a good deal can be done also to make rice a hardier plant through selective breeding; and few attempts at plant development could have greater importance, for rice is a grain not inferior to wheat itself in nutritional value, and one that might be cultivated far more extensively in this country, to very great advantage. My own experiments have had in view the possibility of the development of the American wild rice of the northern lake regions. This, however, is not a true rice, being classified as Zizania, while rice belongs to the genus Oryza. Some twenty years ago I desired to undertake such an experiment, and sent to many places in the United States to get seed of the best varieties. But although I secured seed of the wild rice (it is known to the botanist as Zizania aquatica), my experiment, I regret to say, never got beyond the preliminary stages, because the seed would never germinate. After testing it in successive years I was convinced that the seed of the wild rice must be gathered fresh for planting. For its improvement it would be necessary for men with boats to watch individual plants, and gather seed for immediate planting. The fact that the plant grows in the water accounts, no doubt, for this unusual quality of the seed, as it will not germinate after once being dried like other grains. It grows always in standing water, and is generally collected by the Indians, who are extremely fond of it. They go out in canoes when the wild rice is ripe, and bending the rice over their canoes thresh it from the heads into the boat. During the last year a well-known San Francisco grain firm collected some of the wild rice and kept it moist, and they expect to make a successful introduction of it in this state. Conceivably a commercial variety of importance might be developed that would be hardier and better adapted to the American climate than the Oriental rice. I hope even yet to be able to make the periment. Failing this, I trust that someone else will take the matter in hand.
SOME NEGLECTED GRASSES
If my work with the rice has been only tentative, there are almost numberless allied grasses with which I have experimented on a comprehensive scale. Indeed, I have raised, at one time or another during the past thirty-five years, almost every grass that has economic importance, and many never supposed to have value. Among these several fine varieties have been introduced through Cecil Rhodes of South Africa, which proved enormous croppers in moist, warm regions of this state. Some of these I have grown extensively year after year; others only for a single season, for the purpose of obtaining variation in some useful direction. My work with the familiar giant grasses, Indian corn, sorghum and teosinte, and with the equally familiar small grains, has already been detailed. I refer here to other grasses that are less widely known to the general public, including some that are rarely seen even by the agriculturist. My experimental work with these various grasses has been as diverse as the qualities of the plants themselves. In some cases I have selected for increase of productivity, in others for increase of chemical constituents, or for beauty of plume, or ability to resist drought or frost or wind or moisture; or, again, for compact growing or for ability to spread, or for length and breadth of leaves, or for striping of foliage. The grasses are so numerous and so diversified that there is opportunity for almost indefinite choice as to lines of development, and there are few other groups of plants that offer greater possibilities. To casual inspection, to be sure, most of the grasses seem rather uniform, commonplace, or unattractive. They lack the beautiful flowers that so many other plants present, and their forms, if almost universally graceful, are for the most part lacking in picturesqueness. Add that the grasses present great difficulties to the botanical student because of the minuteness of their flowers and the vast number of species more or less closely related, and you may readily understand why this tribe of plants is so commonly neglected by the amateur. But when we reflect that the family includes the most important producers of food for man and animals; and when we further reflect that there are doubtless many species still undeveloped that might be brought into the company of economic plants, along with wheat, oats, rye, corn, and rice, it is evident that the grasses should be second to no other form of vegetation in their interest for the plant developer. Nor will the plants themselves be found to lack interest when once their acquaintance is made in the right way. They vary in size from tiny sprigs of vegetation to the giant pampas grasses, and to bamboos two hundred feet in height and six inches in diameter. We have already seen that their products comprise not merely universal food and forage for domestic animals, and grains of inestimable value, but juices (in the case of cane and sorghum) that are second in importance only to the grains themselves. We saw too that there are minor products, such as the panicle of the broom-corn, that have no small measure of usefulness. And it is known to everyone that the stalks and straws of the various grasses have a wide range of utility in the manufacture of numerous articles of everyday use, including the mats beneath our feet and the hats on our heads, as well as the food from the tubers of the nut grass. Whereas it cannot be said that a family of plants that is thus comprehensively in the service of man-having had, indeed, a most important share in the development of civilization-has failed of recognition, yet it remains true that there are perhaps thousands of grasses that are almost surely susceptible of great improvement, from the human standpoint, to which very little attention has been given by the plant developer. These present an inviting field for further development. I shall offer in the succeeding pages suggestions as to a few of them, drawn from my own experiences. To attempt to deal with all the neglected grasses comprehensively, and to point out every individual possibility of useful development, would require volumes rather than paragraphs.
A NEW BREAD-MAKING POSSIBILITY
One of the grasses upon which I worked for several years was what is known in the catalogues as "Idaho Brome-grass," classified as Bromus inermis, or Bromus gigantius. I chose this plant on account of its extreme hardiness. It resists drought remarkably, and is very productive. My original seed was received from Montana. I have also grown extensively other species of the same genus, to the number of four or five. My main object was to produce a variety that would yield more forage. Seeds were sown thinly in boxes in the greenhouse, or in plots out of doors. Selection was made when the plants were about half an inch high, and before they had put forth their second leaves. At this stage a fairly correct judgment can be formed as to which plants will be rapid growers. In general, the plant that will ultimately tower above its fellows is found to show superiority in its earliest stages. By selecting the plants that seem to give most promise, and planting these in rows where the soil is practically the same throughout, it is not difficult to discover the most rapid growers and to weed out the others. The brome-grasses are much more variable than is commonly supposed even by those who are familiar with them. In point of fact, even within the same species, it is difficult to find two plants that are precisely alike. Some have broad leaves, and some narrow, and the leaves may be variously curled or twisted, as well as variant in color, some being much darker than others. Some specimens go to seed without producing much foliage; others grow abundant foliage but are tardy of seed-production. The plants that show this propensity to produce foliage rather than seed are, other things being equal, the ones to select, except from the viewpoint of the seedsman, who does not appreciate this kind of grass. I have aimed to get a variety with broad, rich, dark green leaves, and found it comparatively easy to develop such a variety. Notwithstanding the great variation shown by the individual bromes, I found that varieties once specialized tend to come somewhat true to type in the next generation. Therefore it is a very easy matter to improve the different species of bromes. By far my most interesting experiment with plants of this genus was made about twenty years ago with a plant, seemingly of the species known as Bromus mollis, that was found on the edge of the Santa Rosa Creek, about one mile east of Santa Rosa. This wild grass bore a long head of rather plump seeds that were without awns, and that suggested to my mind the possibility of the development of a commercial grain. The seeds were planted and carefully cultivated, and the best seedlings were selected for propagation, with the result that in the course of a few years a variety was secured in which the size of the seed-head was markedly increased, and in which the individual grains are very much plumper than the original one. The grain seemed so promising that I tested it by grinding it in a coffee mill. It was found to produce an excellent flour with a slight yellow tinge. When prepared and baked in the ordinary way, it made a very good bread. I was quite sure that a grain of good commercial value could be produced by further selective breeding from the seed of this brome. But I had only a small quantity of seed, and as other matters took my attention I neglected to plant it for two or three seasons; and when it finally was planted it failed to germinate. So the experiment came to an end in unsatisfactory fashion, yet not without offering interesting suggestions as to the possibilities of development of this and other plants of the tribe. Unfortunately I was not quite sure as to the exact species of brome that furnished the material for this experiment. Moreover, I have not found another plant that showed the same exceptional qualities of seed, with which a new line of investigation might be begun. The one mentioned was discovered only after careful inspection of more than twenty-five thousand examples. But the finding of one sufficiently proves that there must be others to be found if we search widely enough, so I record the experience as a stimulus to farther search and investigation with a tribe of grasses represented by numerous other species that are familiar enough in fields and waste places, but which at present are regarded as weeds rather than as friends of the agriculturist.
SOME CULTIVATED GRASSES
Some of the most striking results I have ever seen in the way of development of grasses were obtained with the perennial known as the Sweet Vernal Grass (Aunthox aithum). This grass is exceedingly variable. A few years ago I raised about fifty thousand plants in boxes. From the seedlings I selected the largest and the smallest; the broad leafed and the narrow; the dark green and the light green; and those showing any other striking peculiarity. By planting the individuals that presented these diversified traits in plots by themselves, and carefully selecting their seed, races of perennial sweet vernal grass were obtained presenting the widest range of characteristics. Thus varieties were produced that would bear almost no seed, and others that bore seed abundantly; some which increased from the roots with great rapidity, and others that increased very slowly. From among the thousands of plants that were raised and scrutinized, I found two or three that would grow more than one hundred times as fast as the smaller ones. Not only was this startling increase in vigor of growth shown at the outset, but it was continued at the same rate season after season, where the plants were raised by division. The differences in the growth of the various plants could be detected almost from the moment when their tips appeared above the soil. But, of course, the selection involved very close scrutiny, and I sometimes spent hours at a time over a box containing perhaps ten thousand to twenty-five thousand plants, selecting two or three that outgrew all others. Here, as with the other grasses, rapid growers in the boxes were almost invariably rapid growers throughout. The seed of the strongest growers was preserved, and the experiment was carried forward with the expectation of developing races of perennial sweet vernal grasses that would not only show improved quality of foliage, but an enormously enhanced capacity for growth. The practical value of such an experiment as this, from the standpoint of the agriculturist, will be obvious. That such variations may occur among plants from the same lot of seed gives a clew to the observed differences of neighboring forage fields. It is clear that the diversities that are usually ascribed to differences of soil may be due in part to different strains of seed. The value of developing a forage grass to its fullest possibilities of productivity is too patent to require comment. That one plant could be made to grow, and to maintain throughout life a rate of growth one hundred times in excess of other individuals of the same species, is a fact that should be stimulative to any experimenter who thinks of working with the grasses, and that is certainly of significance to the cultivator of forage plants. I have experimented extensively also, and with interesting if less picturesque results, with the millets, the rye grasses, and orchard grass, as well as with numberless more or less conspicuous varieties. My work with the orchard grass, which is only neglected in the past few years, included an interesting experiment growing out of the discovery several years ago of a seedling that produced leaves much longer than the ordinary, as well as a large, strong stalk, and a large cluster of blossoms different in form from those of the ordinary orchard grass. The plant was so individual that it could be distinguished at a considerable distance by its greater size and anomalous appearance. The seeds of this plant were found to follow the variant type of their parent somewhat closely. The type has not been entirely fixed but is worthy of further attention. In a few more seasons, according to present indications, it will be so fixed as to produce regularly from seed a type of orchard grass that would nearly or often double the growth of the ordinary variety. Another variable grass that I have cultivated extensively in recent years, for observational purposes rather than commercial varieties, and from which new varieties are being developed, is the species known as Acrostis fontanesi, recently introduced from Algeria. From the same plant have been produced seedlings with broad spreading panicles, others with compact spikes, and yet others with beautiful spreading spikes. On sowing seed from different panicles, it was found that the tendency to compactness or looseness of head was transmitted or accentuated, so that widely differing varieties were developed in the second generation from seed of a single plant. I have obtained some similar results with the Bermuda grass (Capriola), with which I have experimented from time to time during the past twenty years, more particularly in the effort to produce a lawn grass which would fulfil the function in arid regions that the bluegrass fulfils in moist climates. I have found that this grass varies even more than most others do from seed, and by selection was able to produce dwarfed varieties, or, on the other hand, the tallest and largest-growing ones; also varieties with broad leaves and others with narrow leaves. There were plants that came up thickly and made a compact sod, not having the wild running habit of the original variety. And there were others that sent out runners and spread so rapidly that in a single season one plant would cover the ground for ten feet in all directions. These extraordinary diversities were shown among plants selected from the same lot of seeds. In all there were at least twenty quite distinct varieties developed, each marked by one or more obvious and striking peculiarities. But as the Bermuda grass is commonly regarded as a weed, none of these were introduced.
ORNAMENTAL AND USEFUL GRASSES
I have at various times taken great interest in the ornamental grass, commonly known as pampas-grass, the plumes of which were at one time in great demand. The form of pampas-grass that is most grown in California is that known technically as Cortaderia argentea. The plume-like panicles of this grass are familiar ornaments everywhere, and were, in the time of their greatest popularity, articles of some commercial importance. The plumes to be preserved in the best way should not be allowed to come out of the sheath before drying. The long stems, with several leaves attached, are cut just as the tip of the plume begins to show. The leaves are stripped off, and the stalk is placed in the bright sunshine, preferably standing, but more commonly spread on boards or on the ground. Prepared in this way, the panicles do not shake to pieces. They assume the aspect of silky plumes, which are given a peculiar fluffiness and brought to perfection by being placed in a hot oven for a few moments. I have raised perhaps a hundred thousand seedlings of various pampas-grasses, and have crossed them extensively. There is no difficulty in effecting cross-fertilization, provided, of course, the two species bloom at the same time. Pollen from the ripe male plant is simply dusted over the pistillate flower. The female plant is the one that is useful for ornament, the male plant having a smaller and coarser plume, which is never silky or fluffy, and which readily falls to pieces under treatment. There are pampas-grasses, however, that have both staminate and pistillate flowers in the same blossom, and, of course, these cannot be cross-fertilized with such facility. My most interesting experiments have had to do with the crossing of a pink variety of pampas-grass that bears both staminate and pistillate flowers, with some of our finest large white varieties. These plants crossed readily and I raised many thousand seedlings. A large proportion of the seedlings were plants bearing both stamens and pistils like the pink parent. Very few were female plants, and therefore bearers of good plumes. Even when the plumes were produced, they were usually not as large as those of the white parent, and many of them were smaller even than the small plume of the pink parent. This is easily accounted for by the fact that the great white plume has been produced through artificial selection, and therefore its characters were not as well fixed as in the wild type. An interesting feature of this experiment was that the pink color seemed to appear oftenest on the staminate plants and not on those that bore both stamens and pistils. This gives a suggestion of the element of sex selection in heredity, which is seldom observed in plants, although common enough among animals. A further evidence of this was seen in the fact that I was never able to fix the color so thoroughly on the female plants as on the male. The pampas-grass is multiplied by division, so that there is no difficulty about the multiplication of a new variety. The new varieties do not usually come true from seed. But this is of no importance, inasmuch as a single plant may be so multiplied by division as to produce probably fifty thousand marketable plants, on good soil, in the course of two or three years.
SOME MISCELLANEOUS IMPROVEMENTS
From among a great variety of experiments looking to the improvement of farm and forage crops, I will select only three or four additional ones as offering further suggestions. An interesting anomaly with which I have experimented is a hybrid form of the wild oat. A field of the second generation of these hybrid oats furnishes one of the most interesting studies of variation that has come under my observation. Inspecting a field of these oats, sown quite thinly, one finds on the same day some that are thoroughly ripe, while others are not yet in bloom. There is corresponding diversity as to the appearance of the plants, some having broad leaves and some narrow ones. Some of the plants are very tall, and others short and stocky. The panicles are of all forms and sizes. In a word, the hybrids vary in almost every way in which they could vary, and still be recognized as oats. It is obvious that such a variant type of oats gives opportunity for selection and development of new varieties. The tendency to vary as to time of ripening has peculiar interest, as suggesting the possibility of adapting oats-and doubtless also the other cereals-to different climates, or even of the production of different varieties in the same locality, which, by ripening at different seasons, would enable the farmer to avoid the excessive rush of work that attends the harvest season. Several years ago I worked quite extensively on buckwheat. My work consisted largely of selecting the larger, plumper, and lighter-colored kernels. I worked with both the common buckwheat and the Japanese species. A certain amount of crossing was done, but in general the plants were found to be so variable that nothing more was necessary than to select among the different forms that appeared spontaneously. Considerable, though relatively slow progress was made in the production of a better quality of grain. The experiments were discontinued before I began the extensive hybridization of the two species that had been contemplated. They could without doubt be crossed to advantage. Among textile plants, and plants of use in the textile industries, my most interesting recent experiments have had to do with the wild teazel and with the Chilean hemp, that give promise of the production of a valuable fiber. The teazel, as is well known, has been an important plant, inasmuch as its long hooked burrs are used for producing the nap on cloth, more especially the woolens, and no mechanical device has ever been invented as a thoroughly satisfactory substitute. There are several distinct varieties of the plant, and one of them is a weed that grows along neglected roadsides in California. Among any lot of wild teazels one may find a number of types, and it is not unusually difficult to fix these types by selective breeding. If it were necessary or desirable for any particular use to make the hooks several times the usual length, or the burrs themselves several times as large, this could easily be accomplished. My work had to do with some of the peculiar forms rather by way of experiment than with any practical idea. The forms worked with were those with vertical rows of hooks, instead of the spiral ones, and with varieties having extra large hooks at the base and double heads. I carried the experiments forward for several years for my own information and education, and these experiments demonstrated that different kinds of teazel burrs could be developed and fixed if desired. Possibly some modified form of teazel may be of use in a future industry. Hitherto it has not been known that modified forms were available. My experiments with the hemp were conducted largely with an improved Chilean variety, but included also the use of seed from Japan, Russia, and France, as well as from various parts of the United States. The experiments have grown out of a suggestion that I made a number of years ago to a large Boston paper manufacturer, to the effect that it seemed possible that the fiber of the hemp might be used as a substitute for wood pulp in the manufacture of paper. The experimental work is only at its beginnings, but it seems to be of considerable promise, especially as to improved size of plant, as a hybridized variety has been secured which outgrows all other hemps. The hemp, as is well known, is a dioecious plant, and it may be well to mention the simple but uncommon method of making crosses. All the varieties are first planted separately; and only a few of the largest and tallest male and female plants of each variety are left to bloom. When the heads blossom, the tallest of each variety obtained from different sources are crossed with pollen of the tallest male plants. After two seasons of this selection and crossing of different strains from different countries, the varieties were combined by crossing, as before, by selecting the largest and tallest plants, out of which a new race was produced of giant hemp. I found that a hemp received from China and one from Chile were at first the two tallest and most rapid growers, but they were very shy seed producers in this climate, especially the Chinese one. The variety which I produced from Russia was the most slender, and also the most dwarfed, so this had little to do with the giant hemp which was produced. Paper made from the fiber of the hemp is found to be of good quality, and although not generally used heretofore must certainly be more prized as other paper pulps become scarce. I mention this line of investigation here merely to suggest the wide range of opportunities that will open up for the plant developer when he has learned to cooperate with workers in the various industries. Hitherto we have been prone to take it for granted that all the valuable textile plants have been investigated and perfected. The newer studies suggest that there is still almost boundless opportunity for progress, not only through the improvement of the plants that have been utilized, but also through the introduction of species that have been ignored or neglected.
This text is from: Luther Burbank: his methods and discoveries and their practical application. Volume 8 Chapter 9