3% JL ^ PHI pbrarg Jfortl; Carolina jgiate College b94 v. 10 8782 This book may be kept out TWO WEEKS ONLY, and is subject to a fine of FIVE CENTS a day thereafter. It is due on the day indicated below: * \ A Selected Night Blooming Cereus This very fine specimen is the result of careful selection by Mr. Burbank, from large numbers of seedlings. The flowers of this variety are nearly nine inches in diameter. They open early in the morning and are completely withered by ten or eleven o'clock. It will be noted that two of the blossoms on the right hand stalk have withered and that they are marked with strings to indicate that their seed is to be saved for future experiments. Luther Burbank HIS METHODS AND DISCOVERIES AND THEIR PRACTICAL APPLICATION PREPARED FROM HIS ORIGINAL FIELD NOTES COVERING MORE THAN 100,000 EXPERIMENTS MADE DURING FORTY YEARS DEVOTED TO PLANT IMPROVEMENT WITH THE ASSISTANCE OF The Luther Burbank Society AND ITS ENTIRE MEMBERSHIP UNDER THE EDITORIAL DIRECTION OF John Whitson and Robert John AND Henry Smith Williams, M. D., LL. D. Volume X ILLUSTRATED WITH 105 DIRECT COLOR PHOTOGRAPH PRINTS PRODUCED BY A NEW PROCESS DEVISED AND PERFECTED FOR USE IN THESE VOLUMES NEW YORK AND LONDON LUTHER BURBANK PRESS MCMXV Copyright, 1915, fcy The Luther Burhank Society Entered at Stationert' Hall, London All right* reaerred Volume X— By Chapters Foreword Page 3 I Getting the Utmost Variation Out of a Flower — How the Chinese Balloon Flower rj Was Trebled I II Improvements in the Much Improved Iris — And a Few Other Old oq Favorites Oy IH The Tigridia and Some Interesting Hybrids —New Charms in Far-away rjm Flowers i i IV Four Common Dooryard Flowers — And Their Improvement — Work on the Verbena, the Pink, the Petunia and the Geranium. 107 The Everlasting Flower, and Some Common Exotics — The Australian Star Flower and Plants IOC From Orient and Tropics J.OO VI The Hybrid Larkspur — and Other Transformations — Introducing a Miscellaneous -, ^ , , Company # J.0 ( VII Ornamental Palms and Climbing Vines — Views on Artistic 1 «,-» Treatment IV y VIII Lawns and Their Beautincation — Some Old and New Shrubs O O C and Grasses . ^OJ IX Field and Flower Garden — Some Practical Hints for OTft Their Betterment <6 i y List of Direct Color Photograph Prints 305 * $$*<^ w Foreword to Volume X Left in the midst of his flowers, at the close of the last volume, Mr. Burbank in this, the tenth book, continues to unfold before us, more of his transformations. Beginning with the chapter on the means of securing the utmost variation in flowers, he continues with the Iris, the Tigridia, the Ever- lasting or Millinery Flower, the Larkspur, and scores of other beautiful flowering plants, more familiar in the average dooryard. Having covered the range of his flower produc- tions, Mr. Burbank proceds, in this volume, to describe his improvements in ornamental palms and climbing vines, lawn plants and lawn beautifi- cation, concluding the book with a terse chapter on practical hints for the betterment of field and flower garden. THE EDITORS. The Balloon Flower The upper specimen shows the form of the flower just be- fore opening, from which the name is derived. It will be seen that the balloon-shape entirely disappears when the blossom has opened, as in the lower figure. This specimen shows the single row of petals characterizing the variety with Which Mr. Burbank's experiments began. Getting the Utmost Variation Out of a Flower How The Chinese Balloon-Flower Was Trebled IN illustrating the possibilities of flower devel- opment, the case of the Chinese balloon-flower (Platycodon) will answer as well as another. I had been for some time working with a bed of these flowers, with an eye to the increase of their beauty of form, their size, clearness and intensity of color, and the closer and more grace- ful placing of blossoms on the stalk. As to all of these matters, the existing balloon-flowers left a good deal to be desired. My method of work was that which I have already outlined so fully in connection with other flowers. The essentials of it, as the reader is aware, are first the careful scrutiny of the entire colony to discover the individual that is the very best of all as to the particular character in ques- tion. This individual is selected and its seed carefully preserved. [Volume X — Chapter I] nonm library N. C. State Colfefc LUTHER BURBANK If the three or four different qualities, improve- ment of which is desired, are not combined to best advantage in any single individual, then it is neces- sary to select an individual for each quality, and to carry forward three or four lines of experiment at the same time. It will be recalled that in developing a special variety of small sweet canning pea, with the qual- ities of uniform ripening, of small seed, and of seeds of uniform number and equal size in the pod, I was enabled to find these qualities exhibited in such combination that the experiment went for- ward rapidly, so that in the course of six genera- tions I had developed precisely the variety of pea that was desired. But it will also be recalled that half a dozen other lines of experiment were carried forward at the same time, using the same group of peas, that led finally to the production of as many quite different varieties, characterized by large size of seed, by lentil-shaped seeds, and the like. And these secondary experiments were carried out without in any way interfering with the primary one. It was merely that, in searching among the different vines, I could not fail to notice individ- ual plants that showed interesting characteristics, and nothing more was required than to mark these differently from the others and save their seed. [8] Double Balloon Flower This picture, like the preceding one, shows both the bal- loon-shaped buds and the open flower. But this is a developed variety, in which the petals have been increased in number through the methods of selective breeding described in the text. LUTHER BURBANK So in such a case as that of the balloon-flower, where it is desired to increase three or four quite different qualities — in this case size, beauty of form, manner of placement of blossoms, and in- tensity and clearness of color — it does not so very greatly matter whether in the early generations one finds the different qualities combined in a single individual, or whether, as is more likely, he finds one individual that is most graceful, another that has blossoms placed on the stalk in the best manner, and a third that shows to best advantage as to intensity and clearness of color. It is much more probable, in practice, that the second alternative will be the one actually pre- sented. Indeed, it is altogether unlikely, when new qualities, such as these, that have not hitherto at- tracted the attention of the cultivator of the plant, are in question, that one will find a single individ- ual that surpasses all its fellows as to each quality. In point of fact, with the balloon-flowers, it was necessary to save seed of three or four indi- viduals and search among their progeny in turn in the following season, and make additional selections that involved a number of individuals. But when selection has been carried to a stage where we have one race of balloon-flowers pre- senting plants that are uniformly of graceful and attractive form, and another race that has the [10] ON EXTREME VARIATION flowers arranged in a satisfactory way on the stalk, and a third race that produces flowers of a brilliant white color, the materials are in hand for an amplification of the experiment along lines with which the reader is already familiar, through which the desired combination of these traits in a single race may be effected with almost absolute certainty. The Combination of Qualities The method in question consists, of course, in cross-pollenizing the best individuals of the three new races. Of course, one cannot blend three strains in a single cross-pollenizing experiment. But one can cross-pollenize specimens of each one of the three with each of the others, making the cross reciprocal in all cases to make quite sure. Each of the new hybrid races will thus blend, in one way or another, the traits of two of the parent forms. Selection being made to find the best types among these two crossbred races, the ones selected will, of course, be inter-pollenized and their off- spring, representing the second generation from the three parent forms, will combine all the hered- itary factors of their three specialized ancestors. Among these second generation hybrids there will be found, in all probability — if large numbers of specimens are examined — some individuals that [11] 3 3 ■a* ■a fc. il •S CQ CO -5 55 e e °> »•■& SSa" •» a I* «.< So a R. £&% a. 5 a a,* ~ *> «j v> a a a a a L a c. a «j — c a *" 5 * £ «> h © a *s « ?; a O a M ft. J» S a. 5.2 a ON EXTREME VARIATION will combine in the superlative degree the quali- ties of gracefulness of vine of one grandparent with the satisfactory arrangement of flowers of the second grandparent and the brilliant white- ness of blossoms of the third grandparent. It is then an obvious procedure to save the seed of this individual, and while we must expect wide variation among the plants grown from that seed, there will almost certainly be some among them that will reproduce the combined good qualities of the parent, and further selection along precisely the same line — what I sometimes speak of as "line breeding" — will result in fixing of the type, so that we shall have the variety, hitherto existing only in our imagination, which we have all along been seeking to produce. Moreover, not alone shall we have produced a type which combines all the best qualities of the different members of the original balloon-flowers, but our new race will almost certainly present these characters in markedly accentuated form. The perfected balloon-flower will be more grace- ful in form than the most graceful one of the orig- inal colony. It will have its blossoms much more artistically grouped on the stalk than any balloon- flower that has hitherto been seen, and the color of these blossoms will be cleared and more bril- liant than those of any individual member of the [13] LUTHER BURBANK original colony, whether blue, white, or interme- diate, as may readily be demonstrated by compar- ison if the original colony has been preserved, and is now represented by unselected progeny. Of course, in my own experiments, the unse- lected members would usually have been de- stroyed, but the worker who experiments on a smaller scale may find it desirable to preserve the old colony, or some members of it, if for no other purpose than to find encouragement in making such a comparison as that just suggested. The results, as I have said, are sure to be encouraging if you have carried out the experi- ment in the way just outlined. Nothing more is required than the use of your eyes and reasonable judgment in selecting the best specimens; care in the preservation of the seeds; cultivation of the seedlings in the way we have elsewhere fully de- scribed; and persistency in following up the experiment. I have a good many times pointed out that in such experiments there may not be very much encouragement in the first generation or two. Some forms of plant, and in particular those that have not been very much under cultivation, or that are represented by only one or two species, may hold fixedly to their type and show at first only a slight range of variation. In such cases [14] Double, and Tending Toward Tripleness Here the tendency of the balloon flower to increase its petals has taken on another phase, in that there is a rudi- mentary third row of petals, represented by a transformed stamen. This obviously is promising material for further experiments. LUTHER BURBANK you must be content to go forward by very slow stages, taking but the shortest step ahead with each generation for the first two or three years. But even where progress is as slow as this in the beginning, the time will almost surely come when the effect of what I have several times referred to as the momentum of variation begins to be felt. Some season, to your surprise and delight, you will discover that the plants are vary- ing much more widely than they have done hitherto. Instead of having to scrutinize your seedlings with the utmost care to determine which ones are largest and most vigorous; and then in turn scru- tinize with equal care the blossoms — when they appear — to determine which are largest and most brilliant, you will find that some few seedlings will jump ahead of the others as if they belonged to another race, bringing to your mind the famil- iar tale of Jack's Beanstalk, or the less familiar story of Darwin's Hero morning-glory, which ap- peared suddenly after several generations of selection. When the seedlings which thus practically select themselves have come to blooming time, your delight will be enhanced as you discover that the blossoms they bear are markedly larger and more brilliant than any you have seen before. [16] ON EXTREME VARIATION Now all your disappointment and discourage- ment of the first day is forgotten. Now your en- thusiasm is reanimated and accentuated. From this time forward you carry on the experiment with renewed zeal, and you feel confident at last that the coveted goal is within sight. Plants That Tend to Vary Of course there are other plants that give en- couragement from the very outset. Such is the case with almost any of the familiar cultivated plants, of which there are many species and varie- ties that have long been given attention by the horticulturist. Suppose, for example, that you were to plant all the seeds taken from the seed pods of a single dahlia. Perhaps you have done this on occasion, not with any thought of making new experiments or developing a new variety, but merely in the hope of reproducing the characteristics of the best and most beautiful dahlia among the number in your garden. In that case you have doubtless been subjected to bitter disappointment. For when the carefully nurtured seedlings came finally to bloom- ing time, instead of presenting flowers closely sim- ilar to those of the parent form, they have shown, in all probability, the widest range of variation — not one of them perhaps has been closely similar to the parent. Nor, perhaps, were any two pre- [17] Yet Another Step Toward Tripleness With this balloon flower several of the stamens have turned into petals of a rudimentary type. If carefully selected, the progeny of this flower should, within a generation or two, have some representatives with three rows of fully formed petals, in striking contrast with the single-flowered parent- forms a few generations removed. ON EXTREME VARIATION cisely alike. Among them you could discover resemblances to all the other dahlias in your gar- den and, indeed, to a large proportion of those that you had seen pictured in the seed catalogues. In a word, your dahlia seeds show that they contain the racial strains of a great variety of an- cestors, and they present a variation that is truly disconcerting to the gardener whose sole desire was to produce a lot of dahlias of uniform char- acter. In one case, recorded by Darwin, an experi- menter listed no fewer than eighteen different varieties of the dahlia grown in the first genera- tion from the seed of a single plant, and of course there were all manner of intermediate forms. In the listed eighteen only six corresponded pretty closely to certain named or catalogued varieties. It would perhaps more truly present the record if we were to say that there were not eighteen dif- ferent varieties merely, but as many varieties as there were individual plants. But while such an experience as this is utterly disconcerting to any amateur whose only thought is to produce a bed of flowers of uniform color or character, the same experience would offer pre- cisely the opportunity that the would-be developer of new varieties is seeking. Now it is not a case of hunting here and there throughout a company [19] LUTHER BURBANK of seedlings for one that differs by a shade from the others. It is a case of selecting two or three or a dozen individual plants that present features that attract the experimenter; and selecting their seed to be planted the following year in individual plots, that the experiment may be carried forward, generation after generation, just as before so far as principles are concerned — but very differently as regards results, inasmuch as now there is the most striking departure in each successive gen- eration from the characteristics of the parent form. How wide the departure may be within a few generations is well manifested by the dahlias, since these plants, as we have already learned, have all been developed in the space of about a century from wild originals. Moreover, by no means are many generations represented as might be supposed, inasmuch as the dahlia is propagated usually from the bulb, and it is only now and again that an experimenter has taken the plant in hand to raise it from the seed and separate out new varieties. That a plant which in its wild form is an ordi- nary sort of composite — not very different from the Black-Eyed-Susans and allied sunflower-like plants that abound by every roadside — could be developed in a comparatively short series of gen- erations into the extraordianry flower with solid [20] Work with the Calendula Mr. Burbank has a large bed of these flowers in his gar- den now, and in recent seasons he has been testing it with an eye to the range of its possible variations. It is a flower with which any amateur may work readily and to advantage. LUTHER BURBANK heads, and presenting the gorgeous and variegated colors of the dahlia of to-day, is in itself an object lesson in the possibilities of plant development that is nothing less than inspiring. Unexpected Results Not only may plants be led along the line of some desired variation, but there is an element of chance in the enterprise that adds very greatly to its interest. There is always a certain allurement about the happening of the unexpected. It is highly gratify- ing to select a plant for some desired quality and to have it respond to selection in such wise that a variety presenting this quality is finally produced. But it is doubly gratifying to see here and there, quite unexpectedly, the putting forth of a flower of an unpredicted color, or the development of a form of which one hitherto had no conception. In a field of cultivated poppies, for example, where there were millions of specimens, all of sub- stantially identical color, so that the field made a blazing sheet of yellow, I have come upon a single blossom of the purest white. To find this white blossom, isolated among the millions, is an experience that repays one for years of earnest effort and makes amends for almost any antecedent disappointment. It was such a chance discovery as we have seen [22] ON EXTREME VARIATION that gave the world the wonderful new race of white Watsonias. Quite possibly the white flower that Mr. Arderne found among the colony of red- dish pink ones may have been the only one of its color among a million, or perhaps ten million, of its fellows for miles around. But this single atyp- ical individual chanced to be discovered, and its progeny to-day are found by thousands, even by hundreds of thousands, in the gardens and green- houses, not alone of its native home in South Africa, but of all parts of Europe and warmer regions of America. I myself, as the reader will recall, have raised these white Watsonias by hundreds of thousands. Their strains were mingled in the germ plasm of the quarter million bulbs of this species that I was obliged to destroy in a single season. Such are the possibilities of multiplication of a plant. Such is the geometrical ratio at which the offspring of a single individual increase if given encouragement. Boundless, then, are the possi- bilities that lie before the plant developer who discovers a single specimen of an aberrant type. One white poppy among the million yellow ones might be the progenitor of a race that would dis- place entirely the whole race of yellow poppies. What I wish to illustrate at the moment, how- ever, is not the possibilities of multiplication of [23] It <5 so Si 3 I £ -~ « 3 fc * c 5 ^ •5 S 5*«sg«^§~ ■3 5 ~sJE5sS^ 3 e a a 5 •> -5 '2 * " > W *> fc, » ln~ teresting studies in form variation might be made by crossing such a specimen as this with the one shown in the preceding picture. LUTHER BURBANK contact with the pollen of an individual flower only after it has passed the pistil, and the protect- ing sheath prevents the deposit of pollen as the insect or bird leaves the flower. Thus it is insured that self-fertilization will not take place. While the flower is, as I said, complex in this regard, nothing more is necessary than to study its mechanism attentively, pulling to pieces two or three blossoms to see just how the pollen must be deposited. After that you will experience no diffi- culty in cross-fertilizing the iris, and the results of your work are sure to be of interest. Four-O'Clock and Columbine The familiar four-o'clocks are all natives of America, but most of them had their original home in the sub-tropical and tropical portions of our continent. There is one, however, that is native to California, and various species made their way to the gardens even far to the north a century or more ago, and are now grown everywhere. The most striking peculiarity of the four- o'clocks is their tendency to combine different colors in the same flower in peculiar patterns. We have seen a great deal of color variation among flowers. We have seen numberless in- stances in which blossoms of the same species may be in one case red, in another pink, in a third yel- low, and in a fourth white. We have seen also [46] ON SOME COMMON FAVORITES some instances of the mingling of different colors in the same flower, notably with some of the dah- lias. But our attention has been called to no flower that mingles the colors in quite so anom- alous a way as is characteristic with the four- o'clocks. For these blossoms, seemingly unable to decide between different colors, have hit upon a compromise of arranging the colors in definite stripes, which give the tubular corollas a very curious and characteristic appearance. In a lot of seedlings, supposedly of the same variety, the stripes may come in various widths of white, crimson, and yellow. Even when the seed is saved from a single plant, there will be great variation among the seedlings, in some the wide white stripes predominating, in others the crim- son, and in yet others the yellow. Again, some of the flowers may come pure white, or yellow, or crimson, or pink, quite without stripes; or perhaps half of the blossoms on a given plant will be one color and half another. It is obvious that a plant showing such wide variation does not call for hybridization to stim- ulate variation. The mingling of hereditary strains is already sufficiently complex, and you will find quite sufficient occupation in attempting to sort out new races of a good color or combina- tion of colors, and in fixing a dozen of them so [47] A Spectacular Iris Color variation is, of course, the most conspicuous char- acteristic that will appeal to the amateur in the case of the iris. There are purple iris and yellow ones and white ones in almost any garden, and these may be combined in endless ways. Here is a specimen that shows an interesting and spectacular color-blending. ON SOME COMMON FAVORITES that they will come reasonably true to type. If you succeed in accomplishing this, in the course of a few seasons, you will have performed an experi- ment that you will find full of interest, and your task will not have been carried out without giving you very suggestive sidelights on the problem of heredity. It is, in any event, a very curious anomaly that a plant should so have assorted its hereditary fac- tors that they adopt this compromise. And your investigation, which endeavors to determine how accurately the tendency to striping is dependent on particular combinations of hereditary factors, will not only prove interesting, but may lead to valuable revelations. The entire problem of the study of heredity of color, notwithstanding the attention that has been given it, still bristles with unanswered questions. Your experiments with the old-fashioned four-o'clock may serve to give you answers to some of them. A somewhat simpler but perhaps no less inter- esting problem in color heredity may be taken up in connection with the equally familiar columbine. There are thirty or more species of the genus Aquilegia, or tribe of columbine, and examples of one or two of the more common ones are sure to be found in your garden. At least you can get seeds from which to grow them at any florist's. [49] LUTHER BURBANK I have always been fond of the columbines because of their numerous species, and their wide range of color variation; also because of the curi- ous shape of the flower and the tendency of the spurs to vary greatly in length, as well as in their tendency to open out in some cases, and in others to remain partially closed. There is, indeed, one old cultivated variety which has lost the spurs altogether. I made at one time some interesting experi- ments with this spurless kind of columbine, cross- ing it with many others, especially with one known as the coerulea, which has very large flowers of beautiful shades of blue. The hybrids of this spur- less form with the other species produced beau- tiful large climatis-like flowers, some of them three or four inches in diameter. Perhaps the most interesting feature of the experiment was that the hybrids were entirely spurless. This shows that the condition of spur- lessness, which is an anomaly presumably of re- cent origin, inasmuch as the spurs are a character- istic feature of the flowers of the wild columbines, acts as a dominant factor in heredity. This, of course, is what should be expected if it be true that the newly developed characteristics of a plant are dominant over the older ones. But the case of the columbines furnishes another interesting cor- [50] A Round-Petalled Iris Contrast this speciiren, with its almost circular lower petal with the ones shown in succeeding pictures. The char- acteristic iris traits are p-esent throughout; but the modifications in form of petals, ard in the relative sizes of the dif- ferent petals, are very conspicuous. LUTHER BURBANK roboration of this interpretation of Mendelian heredity. In the course of other experiments with the columbines numerous other species were brought into the combination through successive hybrid- izations, until my columbine colony carried the strains of more than a dozen recorded species. A most beautiful lot of hybrids resulted. Their vari- ous members revealed nearly all the colors of the rainbow. I introduced them to the trade as mixed varieties, as it did not seem to be worth while to fix the different types. On the contrary, the vari- ety of blossoms seemed to be considered an advantage. But, in point of fact, even if it had been desired to fix the new types, it would have proved exceed- ingly difficult to do so. When you have two or more species of columbine in combination, the hereditary complications are comparable to those in the gourd family, to which we have had occa- sion to refer. It seems as if every member of a fraternity differs from all other members, and you cannot be at all sure as to what results you may attain by sowing seed from any individual plant. But these complications result in part from the fact that the different columbines are so easily crossed by the bees. This is a case where there is no difficulty in effecting hybridization; the diffi- [52] An Iris with Pointed Petals Here the petals have been modified so that they are pointed instead of round, and their texture is quite different from that of specimens shown in the preceding pictures. Such mat- ters as these have great interest for the gardener, but are prob- ably not vital from the standpoint of the economy of the plant itself; hence they are particularly subject to variation, affording the plant breeder pre- cisely the opportunity he is seeking. LUTHER BURBANK culty is to prevent crosses that are not desired. If the plants are shielded from the visits of the bees, and careful hand pollenizing is effected, there is no great difficulty in combining the different forms in such a way as to get definite results, and the hybrid forms may be fixed by careful selective breeding. Of course, when you deal with a spurless form, if the individuals that you use are themselves hybrids of the first generation of a cross between a spurred and a spurless variety, their progeny, when they are crossed with a spurred variety, will be in effect second generation hybrids and only half of them will be spurless. But this, again, merely illustrates the familiar segregation of char- acters and the reappearance of the recessive trait — in this case the spurred condition — in a rather definite proportion of the second generation progeny. Another anomaly among the columbines that offers good opportunity for experimental tests is furnished by the double varieties. I used to notice that if you crossed a double and a single one, you are about as likely to get a double as a single. Here, again, it would appear that the double con- dition of corolla acts as a Mendelian dominant factor, and that the strains with which I worked were themselves mixed. [54] A Difficult Flower to Cross-Pollenize To casual inspection, the iris does not appear to be a perfect flower. That is to say, it seems to lack stamens and pistils of the ordinary type. In point of fact, the ins has organs of fertilization that are quite petal-like in appearance arranged in such a manner as to provide against self-fertiliza- tion. But intelligent inspection will enable the would-be pollenizer to solve their mysteries without great difficulty. LUTHER BURBANK All in all, then, the columbine offers most in- teresting possibilities for the experimenter who likes to test for himself the principles of heredity. In the matter of color, there is the widest variation, some of the familiar forms being blue, others red and yellow. The curious spurs that characterize the flower, and the fact that some varieties lack them, furnish tangible features that may be tested, and the single versus the double corolla constitutes a third feature that is also susceptible to definite observation and record. So the experimenter who will work with a small number, differing as to characteristics of color and spur and doubleness, has opportunity for watching the interplay of hereditary forces; observing the dominance of certain hereditary fac- tors, and the recessiveness of their opposing fac- tors; and finally the segregation of the different characters and their reassembling in new com- binations in the second generation, that will test his knowledge of the principles of heredity to the utmost, and at the same time will give him definite ideas about the practicalities of plant develop- ment that will be at once interesting and valuable. Meantime the experimenter may introduce problems of far greater complexity if he so desires by mixing larger numbers of the plants somewhat at random, and allowing them to be cross-fertilized [56] . ON SOME COMMON FAVORITES by the bees. In this way he may secure, as I have done in some experiments, columbines of the most wonderful variety. In some of the mixed hybrid colonies, the blending of hereditary factors was so complex that among ten thousand plants there would be perhaps not five hundred that could be classified as approximately identical with one another, or as conforming to a specific type. In other words, there would be perhaps nine thousand five hundred individual plants, each of which might be said to constitute a distinct variety. In the course of these experiments I made per- haps ten thousand careful hand pollenations be- tween different specimens of these variant hybrids, and, needless to say, secured plants with excep- tional blossoms of many kinds. A similar line of experiment is open to anyone who has the smallest plot of ground in which he can grow a few scores of columbines. Campanula and Coreopsis If you were to seek experiments of a still sim- pler character, you might do well to consider the beautiful campanula, known familiarly as the bluebells of Scotland. These are hardy flowers, growing wild in great profusion, even far to the north. On a trip to Canada a good many years ago I was delighted to [57] An Ingenius Mechanism The stigma of the iris has a little lip under the unique petaloid pistils, adjusted in just the right way to scoop the pollen off the back of a bee as it enters the flower, or from the head of a humming-bird. The bee or humming-bird will come in con- tact with the pollen of this flower only after it has passed the pistil, and the protecting shelf prevents the de- posit of pollen as the insect or bird leaves the flower. It is a most ingenius and interesting arrangement. ON SOME COMMON FAVORITES see great fields of companula as far north as Alberta. They are said to grow even in Siberia. So whatever the location of your garden, you will probably have no difficulty in raising bluebells. The plants, to be sure, are somewhat subject to the attacks of fungus pests and insects, but aside from this difficulty they are easily grown. It goes without saying that a flower that has become famous as the "bluebell" is generally blue in color. Yet it is by no means unusual to see specimens that are pure white. And it is this variation that gives opportunity for some simple experiments in cross- breeding. Nothing more is needed than to secure plants of the ordinary blue variety and others that bear white blossoms. The campanulas are easily crossed, and you will have opportunity to test the color variation in heredity in some of their sim- plest relations. There are, to be sure, many spe- cies of campanulas, and it is true that the garden varieties are likely to have been hybridized. I have, for example, raised seedlings from the white campanula, Rotundiflora, without securing any white ones. It will be necessary, therefore, for you to test your varieties by raising plants of uncrossed seeds at the same time that you are making the cross-pollenations. But this complication will only add interest to the experiment. [59] LUTHER BURBANK The many tribes of coreopsis give opportunity for experiments of equal interest. These plants are composites, and in hybridizing them it will be necessary to use the method detailed in our story of the dahlia, washing away the pollen before applying pollen from the other flower. The different members of the family vary in color from deepest purplish crimson to light yel- low and white. There are numerous species under cultivation, and there are wild ones growing as roadside weeds that are readily accessible. The variability of the different races makes them an interesting race with which to work. My own work with the tribe has included a good many species, the most important of which is the one known as the Coreopsis linceolita. The experiments look to the increase of the number of florets, as well as to the size of the flowers and abundant bearing. I also had in mind improving the form of the plant. There was no great diffi- culty in doubling the size of the flower, and in the course of four years, working with seed purchased in the common market, varieties were produced that were considered worthy of introduction, and that were distributed by several leading florists. The developed varieties had exceptional value because of the large size of the flowers and of the small center; also because of the long stems, mak- [60] A Luxurious Type There is something peculiarly oriental and luxurious about the appearance of this particular variety of Burbank iris; the idea being carried out by the richness of coloration and the softly- flowing contour of the petals. In point of fact, however, the oriental iris is of a somewhat different type, as will be seen in succeeding pictures. LUTHER BURBANK ing it a good flower for cutting. A fault of many of the annual varieties is that they have small, weak stems. As to all of these matters, the amateur can work by selection and by hybridizing. The wide range of color variation affords a ready guide in hybrid- izing experiments, and the ease and certainty with which the plants can be grown from seed adds greatly to their utility from the standpoint of the amateur. Shooting Star and Salvia A really fine plant that offers opportunity for improvement, yet which has been little worked with, is the Shooting Star, sometimes called Amer- ican cowslip, a member of the primrose family, classified under the genus Dodecatheon. There are sixteen or eighteen species described in botanical literature, yet so great an authority as Asa Gray thought that all the Dodecatheons in the world should be classified as one species. There are remarkable variations in size and color, however, yet the varieties are sufficiently fixed to offer good opportunity for experiment, and at the same time are closely enough related to that they may readily be crossed. The flowers of the various types show the wid- est variation — dark purple, crimson, rose, white, spotted, cream color, and yellow. There is oppor- [62] A Japanese Iris Mr. Burbank's experiments, as already mentioned, have largely had to do with the Japanese iris. He raised great quan- tities of them at Sebastopol a few years ago. The combinations of colors are beautiful beyond description, and they vary in all shades of the rainbow. Sometimes the double ones take on handsome and unusual shapes. These are typical specimens of a more usual form. LUTHER BURBANK tunity for sorting out individual colors and their fixing through selection; and, on the other hand, for the combination of colors to produce new shades. The plants are handsome, and they furnish admirable material with which to work, not merely by way of gaining experience, but also with the possibility of producing worthy new varieties. The Salvia are members of the mint family. There are many species, showing a wide range of variation. The commonest one is known in every garden for its brilliant red flowers borne in such profusion as to make splendid masses to group along walls or as borders. There are other sal- vias, however, that have charming light blue flow- ers. The plant in the ordinary gardens is grown, of course, only for its flowers, yet there is a species, known as Salvia sonomensis, or Salvia ramona, that is abundant on some of the hillsides in Cali- fornia, and that is to all intents and purposes iden- tical with the cultivated sage. Its foliage has the exact flavor of that of the cultivated plant. I have at times thought of growing it to see if there could not be developed from it a sage that would be more valuable for seasoning than the one under cultivation. The common sage runs into numer- ous varieties, some woolly leafed, some golden leafed, and some with tri-colored leaves. [64] Seedling Japanese Iris This is one of a multitude of variants among the seed- lings of the Japanese iris. It is probable that these plants were stimulated to vary by the change of climate and soil. We have seen numerous illustrations of similar effects of a changed environment. LUTHER BURBANK It is possible that by hybridizing this plant with the wild variety improvement would be made in the unique quality for which its leaves are prized. From the present standpoint, of course, our in- terest in the salvias concerns their flowers. I have done a great deal of work with various members of the family, both in the way of selection and of hybridization. The plant is tremendously vari- able, even within the same species, and the various forms run more or less together so that it is diffi- cult differentiating them botanically. But the con- trast between the species bearing blue flowers and the familiar garden plant with its scarlet blossoms is striking enough to challenge the attention even of the least observant. The fact that the various species can readily be hybridized, while at the same time they show such variation as to color of blossom, gives them obvi- ous interest from the standpoint of the amateur plant experimenter. It should be noted, also, that there are some salvias with white leaves, one of these having foliage so thoroughly covered with a white thick wool-like growth that the leaves make excellent pen wipers. The experimenter who works with one of these varieties could doubtless develop interesting modifications of leaf through selection alone, and, of course, hybridizing meth- ods could be utilized to accentuate the variation. [66] More Japanese Visitors These flowers suggest the range of variation in form and contour and color among seedlings of the Japanese iris. Many of the variants are beautiful, and some are grotesque, and all of them are highly interesting from the standpoint of the plant developer. LUTHER BURBANK A plant that is exceptionally interesting because of the work that has been done with it in recent years is the familiar evening primrose (Oeno- thera). Mention has been made in another place of the famous work of Professor DeVries, which fur- nishes the foundation for his celebrated theory of mutation. It will be recalled that Professor De- Vries found specimens of evening primrose that departed so widely from the form of their parent as to seem to constitute new species. The question whether these mutations were of unexplained origin, or whether they were really due to hybrid- ization, is still perhaps an open one. But, in any event, the use made of them by Professor DeVries called particular attention to this plant, and has given it a place quite apart among flowers of field and garden. There are many species of evening primrose, and the tendency to vary among them is marked. Variation, however, does not extend to the flower. There may be all manner of modifications of stem and leaf, but the typical blossoms of the evening primrose are of a pleasing pale lemon yellow. My Primrose Experiments I have experimented with the primroses, cross- ing them quite extensively. One form that was received from the mountains of Chile has given [68] Unnamed Flowers from China Here are blossoms of an unknown species of flower, obviously closely related to the iris, the bulb of which was sent to Mr. Burbank from China. The gardens at Santa Rosa teem with nameless exotics, all of which are sure to be tested as to their propensities and capacities. LUTHER BURBANK some interesting results through selection, in that it now produces blossoms, a single petal of which would cover the entire blossom of any of tne larger primroses under cultivation. The flower itself is sometimes six inches or more in diameter. A bed of these plants reminds one of a lot of handker- chiefs spread out on a lawn, as the blossoms are somewhat square with rounded corners. A new crop is produced each morning throughout the entire summer. The plant itself is somewhat trailing, and about two feet to two and one-half feet in diameter. It is a perennial, though it commences to bloom quite early in the season. This large flowered variety has been produced by most rigid selection for size, form, and white- ness and substance of flower, and it far surpasses all other members of the genus in size and beauty. I have hybridized this Chilean race with the common Oenothera acaulis, or Taraxacifolia, and produced a large number of intermediates, from the best of which I have made selection. These hybrids seem to come absolutely true in the sec- ond generation, so far as foliage is concerned, being in all cases intermediate between the two species. This is perhaps what would have been expected in a member of this race, in view of the observations of Professor DeVries. The plant [70] Selected Chinese Iris Note how widely this flower differs in form and general appearance from the iris shown in earlier pictures. Such variations are always a source of gratification to Mr. Burbank, as they furnish obvious material for crossbreeding experiments. Interesting tests of the present flower have been made in that connection. LUTHER BURBANK seems to have an exceptional propensity to form new types. This, of course, is precisely the characteristic that gives the plant interest from the standpoint of the amateur experimenter. So a plot may very well be set aside in the flower garden for some evening primroses of two or three species. Hy- bridization will readily be effected by the insects, if the experimenter does not care to take the trou- ble to hand-pollenize the plants, and the produc- tion of some interesting new forms may fairly be counted on. I will name only two other common plants from among the almost numberless ones that might be selected, as offering advantageous material for selection by the amateur experimenter. But these are about the commonest of all, and in some re- spects among the most beautiful and interesting — the golden rod, and the aster. These plants are almost universally associated when growing wild in the field, and their blossoms form so beautiful a contrast that the two may very well be trans- planted to the garden together. I have experimented quite extensively with the goldenrods, and at the same time made a collec- tion of the native asters. And while the two plants are so very different, the fact that they blossom together late in the fall and harmonize so beau- [72] An Improved Evening Primrose Mr. Burbank has worked extensively with the evening primrose. This one is a species from South America, which attains altogether unusual dimensions, some specimens suggesting a small handkerchief spread out on the foliage. Mr. Burbank s experiments with the evening primrose have convinced him that Professor DeVries' celebrated mutants of this tribe are in reality hybrid forms. LUTHER BURBANK tifully in the landscape, makes it worth while, as I have just suggested, to work on the two in com- bination. The golden rods are of so many species and so variable that they tax the skill of the botanist. To differentiate between them accurately is a task lying far beyond the skill of most amateurs. But for that matter, it is my observation that the dif- ferent species hybridize so freely when growing wild that the specific lines are thoroughly broken down. Any botanist who pretends to fix hard and fast lines between the different species of golden rods, and does not take account of the hybrids, which are even more numerous in many localities than the parent forms, will not gain a very adequate idea of the golden rods as they actually grow. Any species of golden rod will serve the pur- pose of the experimenter. But, of course, it is desirable to have a number of species, and it is obviously worth while to make careful selection in deciding which ones to transplant to your gar- den. I have spent many days on a few acres of ground, searching among the multitudes of golden rods for the most beautiful individual specimens. From these selected seed was collected, or the roots themselves dug, to furnish the basis for further experiment. [74] A Spray of Goldenrod There are numerous species of goldenrod and these grow in neglected fields almost everywhere. Mr. Burbank found that the different species constantly hybridize in a state of nature. He suggests that the goldenrods are very interesting flowers for ex- periments by the amateur in crossbreeding and selection. LUTHER BURBANK Some of the wild forms seem almost perfect, yet when taken under cultivation and carefully selected they prove susceptible of betterment. The hybrids, in my experience, are not as vari- able as might be expected. But this is no doubt because the plants with which we worked were themselves hybrids. In point of fact, one can sel- dom be sure, in working with the golden rods, that one is working with pure species. But such complications, of course, give added interest to the work of the plant developer after he has the fundamentals of the method fairly in hand. And I can think of few problems that would be more interesting than to attempt to untangle some of the hereditary complications among the golden rods. The fixing of types by selection; the improving of the best existing ones; and the devel- opment of new types by hybridization — these are all methods that offer opportunity for fascinating experiments. Whoever takes the trouble to make friends of the golden rod is not likely to regret his experience. — Any old-fashioned flower garden will furnish abundant material for all the experi- ments that any amateur need care to undertake. The Tigridia and Some Interesting Hybrids New Charms In Far Away Flowers ABOUT a quarter of a century ago I com- menced cultivating and crossing all the Tigridias, or Tiger Flowers that were then offered by any seedsman or nurseryman anywhere in the world. I also secured all the species of the allied genus Ferraria that I could obtain and cultivated them for the purpose of hybridizing them with the tiger flowers. The Tigridias are natives of subtropical and tropical America, ranging from Mexico to Peru and Chile. The Ferrarias are from the Cape of Good Hope, and are represented by a number of species. Both tribes belong to the Iris family, and the two forms are so closely related that by some botanists they are regarded as properly falling within the same genus. My own experiments, which show the ready [Volume X — Chapter III] LUTHER BURBANK hybridization of the various Tigridias and Ferra- rias, suggest that they are closely related. Yet the fact that they are indigenous to different conti- nents shows that they have been separated for a very long period of time, although doubtless of common ancestry. The students of geological botany tell us that there must have been a great mass of land in the southern hemisphere at one time on which races of plants developed that subsequently were iso- lated on the land masses that are now known respectively as South America, Africa, Australasia, and New Zealand. At that remote period the Tigridias and Ferrarias were doubtless of one stock, and the fact that their descendants of to- day retain such elements of affinity as to puzzle the botanists and to serve well the purposes of the hybridizer gives another illustration of the won- derful pertinacity with which the characteristics of a plant are sometimes transmitted through almost numberless generations without radical transformation. It is little wonder that the earlier biologists, before the coming of Darwin, when confronted with such observed cases of affinity between races that must have been separated for countless thou- sands of years, were strong in their faith in the fixity of species. [781 The Interesting Tigridia The tiaridias are very Interesting lily-like flowers from the tropics. Mr. Burbank has experimented with them very extens- ivelu both by way of selection and through crossbreeding. Some of tlu results of these experiments are shown in succeeding pictures. LUTHER BURBANK Yet the facts of variation, even within a few generations, are too obvious to escape attention. And the compromise has been found, as every- one knows nowadays, in a recognition of the fact that time is long, and the further fact that natural selection may be instrumental in maintaining the fixity of a race, provided the environing conditions are unchanged, just as it may be instrumental in somewhat rapidly changing the form of a race when the environing conditions have altered. Hybridizing the Tiger Flowers From the outset I found that the various tiger flowers throve in my gardens, particularly in the sandy land at Scbastopol and in sandy beds especially prepared for them at Santa Rosa. As I have already said, I began at once crossing and hybridizing the various species and varieties, and of course carried out selection among the seed- lings and made new crossings, according to my usual custom. The type species with which the experiments began was the Tigridia pavonia, of which there are numerous varieties. Another form known as the Conchiflor or Shell flower was uti- lized, and subsequently the T. buccifera, a form more recently introduced from Mexico. An especial effort was made to introduce also into the combination the strains of a plant of yet another genus, the Herbertia platensis. This is a [80] ON THE TIGRIDIA tall-growing plant bearing close resemblance to the Tigridias, and by some botanists classified with them. It has pale blue flowers marked with yel- low, and the specimens are of a somewhat different structure from those of the Tigridia, though the bulb and general growth of the plant are similar. I particularly desired to introduce strains of the Herbertia platensis, because this is a very strong-growing plant, and its vigor and health would be of great service in giving hardiness which is the one thing that the Tigridias more especially lack. In particular, the bulbs of the tiger plant are difficult to keep over winter, and especially subject to decay from exposure to air and to the attacks of aphids when stored. But much to my disappointment I was never able to effect hybridization between any of the Tigridias, either pure bred or hybrid, and the Her- bertia. The experiment was made over and over, and in every case it was without result. Meantime, however, there was no difficulty whatever in hybridizing the ordinary cultivated strains of Tiger Flowers among themselves and with some of their South African relatives. And the results of such hybridizings were manifest almost from the outset. One of the most striking modifications shown [81] Hybrid Tigridias The word tigridia or tiger flower, would suggest a striped flower, whereas in point of fact this flower is spotted. Mr. Bur- bank suggests that the word "leopard" or "panther" would have been more appropriate; and that the term "jaguar flower" would have been still more significant, inasmuch as the tigridias come from South America, the home of the jaguar. The specimens here shown are hybrids of a very interesting type. ON THE TIGRIDIA by the hybrid Tigridias was the development of varieties having striped flowers. It might very well be expected that a "tiger flower" would be striped. But in point of fact the native Tigridias are spotted and never striped. They might with much greater propriety have been named after the leopard or panther, or better yet, considering their origin, after the South American jaguar. But the botanist who originally named them seemingly had rather vague notions as to the markings of the coat of the tiger, or else considered it sufficient that the flower itself wears a yellow mantle with dark markings. In any event, there is something about the aspect of the flower that makes the name "tiger flower" seem not inappropriate. And the propriety of the name becomes quite beyond challenge when my new hybrid varieties are under observation. For these are striped in a way that is very striking. Quite aside from its suggestions as to one feline or another, however, the new hybrids are flowers of great beauty and interest and differ conspicuously from any of the parental forms. Not only are the markings thus conspicuously altered, but the flower itself is greatly increased in size. The tendency to freedom of bloom is accentuated. Moreover the hybrid plants have [83] LUTHER BURBANK gained greatly in vigor of growth, in hardiness, and in resistance to disease. The colors of the new flowers are conspicuously brightened. The striping is usually crimson on white, crimson on yellow, or yellow on crimson. In addition to presenting these stripes, which are quite unlike any marking of the native Tigridias, the hybrid flowers generally retain the dotting at the center that characterizes the tribe in its origi- nal form. But these dottings are greatly increased in size. In some instances, on the other hand, the dottings are partially or entirely eliminated. The original types of these very striking new forms of Tiger Flower were readily fixed so that they breed absolutely true from the seed. It was possible, however, to increase the size of the flower by selection, and this increase in size was a permanent acquisition; also to add brilliance with new combinations of colors. And of course the hybrid plants thus perfected exceed greatly the size of any plants that could have been developed by mere selection without crossing. Utility as Well as Beauty The new tiger plants, although still lacking something of hardiness, were greatly improved in this regard over their ancestors. Most of the old tigridias, as I have said, are [84] Another Hybrid Tigridia None of the tiger flowers are striped, which seems to make their name inappropriate, as already suggested, ■ neverthe- less there does seem to be something tiger-like about this richly ca- parisoned and oriental-seeming flower. It is rather curious to reflect that the spots on the flower are intended to make it conspicuous, whereas the striped coat of its namesake is calculated to make the animal invisible in the jungle. LUTHER BURBANK quite subject to insects and disease. The hybrid forms are much more resistant. There is also a greater power on the part of the new plants to stand sunshine. The old tigridias sometimes with- ered under the influence of the sun. This might not at first thought be expected of a tropical plant, but it should be recalled that the growth of vegeta- tion in tropical regions is so luxuriant that low- growing plants of this order are not usually sub- ject to the direct rays of the sun throughout the day. It goes without saying that the bulbs of the new tiger plants were improved in proportion to the stalks and flowers. The bulbs of the tiger plant are elongated and tunicated, and multiply by division somewhat after the manner of the hyacinths, tulips, and the allied races in general. The bulbs of the new hybrid tigridias were doubled in bulk, and in some cases quadrupled, as contrasted with the parent forms. Like the some- what similar bulbs of the gladiolus, they may best be kept in the ground over winter here in Califor- nia, instead of being taken up and stored as is necessary in colder climates. The development of the bulbs of the tigridias has not been at all a matter of accident. At all stages of the experiment in hybridizing and selec- tion, I have paid the most careful attention to the [86] Variant Hybrids It will be seen that the different tigridias hold rather closely to the same characteristic type of flower. There is, nevertheless, a good range of variation as to size, precise contour of petals, and color. Of course the hybrids show combinations of characters that are not united in any single one of their parents. There is the usual tendency to the segre- gation of these characters into many new groups in the second generation. LUTHER BURBANK condition of the bulbs, selecting always those that were largest, firmest and soundest. And the reason for this was not merely that such bulbs usually produce the best flowers, but also that it is worth while to improve the size and quality of the bulbs quite on their own account. The particular reason for this is that the bulbs of the Tiger Plant are edible. When cooked like potatoes, or made into a stew, they constitute a really delicious vegetable. To my taste the bulb of the tiger plant is at least the equal of any vegetable under cultivation. It is also highly nutritious. I am not sure that it has an equal among the vegetables of our gardens in its combination of nutritiousness and appetizing flavor. These very qualities lead to its destruction by all lands of animal and insect life, like the Lilium Brownii, which has no bitter principle, containing sweet and nutritious matter, and which also is attacked and appropriated by insects and other creatures. As yet the tigridia is too tender to gain a place in the vegetable garden on a footing with the potato and allied bearers of bulbs and tubers. But when through further breeding experiments, it has been rendered more amenable to general culti- vation, its bulb being at the same time still further [88] Seedling Tigridias The wild species of tigridias of course breed true from the seed. But, equally of course, the hybrid forms cannot be expected to do so. So there are fascinating possibilities of variation among the progeny of any hybrid. Yet even the most widely varying specimen is at once recognizable as a tigridia. LUTHER BURBANK increased in size, the tiger plant may come to be valued for its edible bulb quite as highly as for its beautiful and spectacular flower. Multiplication by Bulb Division The habit of storing nutritious matter in its bulb, and the further habit of producing collateral bulbs from which new stalks will grow, so that the plant multiplies indefinitely in this way, is charac- teristic, as everyone knows, of a large number of plant families, many of which have come within the scope of our studies. The phenomenon of bulb division, indeed, is so familiar to everyone who has experimented in the vegetable or flower garden as to take its place among those familiar matters of fact that call for no comment. Yet if we consider the matter thoughtfully it will be clear that this habit of putting forth offsets from a bulb as the basis for the development of new plants is an altogether extraordinary phenom- enon— quite as mysterious, indeed, as the produc- tion of the seeds that bear the complex hereditary factors and transmit the qualities of a race of plants from one generation to another. There is, in point of fact, no fundamental dif- ference between the production of new plants by bulb division and their production by seed, except that in the latter case there is opportunity for the [90] ON THE TIGRIDIA union of two different racial strains, one borne by the pollen and the other by the ovule. This, to be sure, is a difference that has very important prac- tical bearings, inasmuch as the union of two dif- ferent hereditary strains gives opportunity for the blending of hereditary factors and their re-com- bination, thus compelling variations that furnish the basis for natural or artificial selection, through which new races are developed. All this needs no explication here, as our earlier studies have made it perfectly familiar. But what I wish now to emphasize is the fact that the bulb that produces a new plant carries the hereditary factors of the parent plant substantially as they are borne by the ovule or the pollen grain that the same plant puts forth on its aerial stalks, and exactly as the bulb of any plant — in fact, the bulb of any plant is only a fat, immature, under- ground bud. If the ovule could develop without being fertilized, or if the pollen could grow into a plant, the result in either case, we may reasonably assume, would be a reproduction of the plant closely similar to the parent form, just as the aphids and the bees when parthonogenetically produced, and in a few instances of plants, for example, the violet. Yet there are differences between the different pollen grains and between [91] 3 C o ? -5 g 5 § 4> a. 5 o S 2 B*i ta« 5 «. "© ^ sib © a «> -s i: « - 1.2 a © ». a 3 « «j id *; a ©" 55 * 5 « c*rSS~ 25 © «5« sj^S^oc: a-c a « c a § 2 -2 4? Si •ft© ON THE TIGRIDIA the different ovules of the same plant, as demon- strated by the fact that flowers, for example, of different hues may be borne on plants grown from a single seed pod. So if we are to present the matter quite in its true light we should say that the aggregate pollen- product and ovule-product of a plant must be con- sidered as representing the personality — that is to say, the hereditary complex — of the plant. No single pollen grain and no single ovule contains representatives of all the types of heredi- tary factors that are present in the germ plasm of the plant as a whole. Stated otherwise, the pollen grains and ovules are very specialized and concentrated portions of matter, each of which contains a similar equip- ment of the most fundamental of the hereditary factors, but each of which contains a somewhat different assortment of the less fundamental ones. All the plants that grow from the seed of a tigridia, for example, will be unequivocally tigrid- ias in stem and leaf. But there will be minor dif- ferences among them as to details of size, as to freedom of flowering, as to precise size of flower, and as to the exact distribution of the color markings. As a matter of course, when the seeds are the product of cross-pollenizing, the offspring, repre- [93] Bulbs of the Tigridia This large tigridia bulb is developing a cluster of small offshoots. Each of these little bulbs will produce a plan J, dupli- eating almost absolutely the original parent form There is no , such range of variation among plants grown from bulbs as among those grown from seeds. The bulb of the tigridia has exceptional interest because it is edible. ON THE TIGRIDIA sen ting now two parents, will show a still wider diversity of hereditary traits. Meantime, turning attention again to our bulb, we find that this structure represents the parent form with much greater fidelity. As nearly as there can be identity between two different living things, the plant that grows from any offset of the bulb of any given Tigridia will be identical with the parent form. A certain amount of diversity there must always be, because no two living organisms are absolutely identical. But for all practical purposes it may be said that the different plants grown from offshoots of an original bulb are identical. The process of bulb division can be repeated a thousand or a million times, until the original bulb has been so multi- plied that its descendants people the earth. But from first to last, one bulb will be substantially like another, and all the myriads of plants that have thus arisen may be said to constitute a single personality. All this is such familiar matter of fact as to excite no comment. Yet, rightly considered, it is a fact of the most mystifying kind and one that must excite wonder- ment on the part of anyone who gives it serious consideration. [95] LUTHER BURBANK That the multitudes of hereditary factors that exist in the germ plasm of so complex an organism as a flowering plant should be grouped in each successive bulb that develops as an offshoot of the original bulb of that plant in precisely the same combination, pre-determining the production of a future plant identical with the original, is a fact that becomes increasingly mysterious the more carefully we consider it In particular, the mystery is great if we have kept in touch with modern ideas as to the segrega- tion of the germ plasm and the body plasm of the living organism. There is a current notion, sup- ported by high scientific authority, that the very earliest division of a fertilized egg cell, in the case of an animal or plant, results in the separation of the infinitesimal fleck of protoplasm into two dif- ferent parts that are fundamentally different, one carrying the body plasm from which the structure of the new individual is to grow, and the other carrying the germ plasm that is to convey the potentialities of future offspring. New studies in the biological laboratory have shown that this idea, that the first division of the egg cell results in such a segregation of body plasm and germ plasm, cannot be fully accepted. Nevertheless it is obvious that in the case of all higher organisms, whether vegetable or animal, [96] A Blue Tigridia Here is a Burbank hybrid tigridia that has taken on a color variation that is very striking. It is a complex hybrid, further developed by careful selection in Mr. Burbank's garden. represents the result of one of his most interesting series of experiments in breeding the tigridias. LUTHER BURBANK the germ plasm may be a thing apart. As finally segregated, for example, in the ovules and pollen grains, it constitutes a concentrated aggregate that transmits the hereditary factors from generation to generation in a sense independently of the bodily characteristics of the individual plant. You may, for example, determine that a given flower and the seed that grows from it shall be of exceptional size and vigor by cutting off all other flowers so that the energy of the plant shall be concentrated on a single one. But in so doing you merely give added vigor to the new generation; you do not alter its fundamental hereditary char- acters. These are pre-determined by the factors in the germ plasm that have been brought from earlier generations and of which the individual plant is only the carrier. All this, then, suggests the isolation of the germ plasm; and the newest theories of heredity have tended to emphasize the idea that germ plasm and body plasm are things of a somewhat different order. Yet the phenomena of reproduction by root division or by the putting out of new bulbs, fur- nish a striking demonstration that the germ plasm which predetermines the form of the future plant is present not alone in the pollen grain and the ovule, but also in the bulb. [98] ON THE TIGRIDIA Even from the single bud of a bulb, as we have seen illustrated in several cases, a new plant will grow that will duplicate absolutely — in the inter- pretation just given — the qualities of the parent plant. And when we were studying the fruit trees we saw that the same thing is true of any aerial bulb if grown even on a foreign branch. Root bulb and aerial bulb alike contain the essential germ plasm of the individual of which they are a part. They nurture potentialities of a new individual that will duplicate the parent form. Germ Plasm and Body Plasm From all of which it follows that the germ plasm of the plant cannot be thought of as isolated from the body plasm. It may well enough be segregated within the substances of any given cell. But that it is present in connection with the living cells of the plant everywhere, from its roots to its remotest stem, is clearly demonstrated by the every-day methods of propagation employed in orchard and garden. Such being the case, it is difficult to avoid the conviction that the germ plasm that is part and parcel of every cell of the body plasm of the entire plant is more or less subject to the environing influences that effect the body of the plant. And from this it would follow, at least as a reasonable inference, that environing influences that modify [99] Co *> "5-2 ■ • •Si T3 o *s ©•Sit; 5 < -c -S 'c o ap». ?oa •» craa'c £e£ "■S.SS-3 .5 a * .2 g — ^ C °! 5 " •* h B '» «» ••» a o i- © *> ON THE TIGRIDIA the structure of the plant body must have an effect in modifying also the germ plasm in a way to influence the character of the future plant that develops from that germ plasm. And as much as this, it should be added, is admitted by all experimenters, even by those who deny the possibility of the transmission of acquired traits in the older interpretation of that phrase. That altered conditions of nutrition may modify the condition of the germ plasm in such a way as to modify the state of the offspring has been shown by experiments in many fields, both with animals and vegetables. Such being the case, the question of the transmissibility of acquired traits is reduced, as I have elsewhere quoted an authority as saying, to a matter of definition. Nevertheless, for practical purposes, it is unquestionably true that the germ plasm is enor- mously difficult to influence, and that under all ordinary circumstances it will convey its heredi- tary factors unchanged, or not appreciably changed, from one generation to another. In attempting to modify the forms of successive generations, the method that has hitherto proved successful, has been, not the modification of the individual germ plasm, but the bringing together of different germ plasms trom diverse organisms through hybridization. [101] LUTHER BURBANK For such union of germ plasms there is obviously no opportunity in the case of the new plant grown from the bulb. Hence the fixity of type of plants propagated in this way — a fixity that is often of the utmost prac- tical importance, as in the propagation of a new race of vegetables or flowers, but which, by the same token, puts the plant thus propagated outside the field of the plant experimenter. Complementary Modes of Propagation Thus the two methods of propagation that are available for such a plant as the tigridia and for countless others of its ilk, are in a sense antago- nistic or complementary in their influence on the history of the plant itself. Propagation by bulbs insures spread of the race, but insures also maintenance of the racial fixity. Should environing conditions change, it is unlikely that plants thus propagated could change rapidly enough to adapt themselves to these conditions. But at the same time that the plant is producing new bulbs it may also, year by year, produce seeds that are the result of cross-fertilization. And this method of propagation is a perpetual bid for such variation as will make possible a relatively rapid change in adaptation to a changing environment. [102] A Nameless Missionary Flower This odd flower was grown from seeds sent Mr. Burbank by a missionary from China. Many interesting results have been obtained at Santa Rosa by experimenting with flowers sent by missionaries. In this case, the similarity to the tigridias sug- gests the possibility of hybridizing experiments, which, however, have not as yet been undertaken. LUTHER BURBANK That vast tribes of plants should have found it necessary to adopt both methods of propagation is in itself an evidence of the struggle for existence that is the basis of natural selection. In another way, also, the bulb perhaps evi- dences the hardness of the struggle for existence, particularly in tropical climates. Everyone knows that vegetation is exceedingly luxuriant in the tropics, and it is a matter of observation that the habit of developing tubers and bulbs is especially common among the herbaceous plants of tropical and sub-tropical regions. Perhaps one explana- tion is that the storing of food-supplies in the bulb enables the young plants to shoot up rapidly without waiting for the development of a large root system. By so doing they may stand a chance of com- peting with the surrounding vegetation and thus have a far better chance of reaching maturity than if they had grown from tiny seeds. It is probable, therefore, that the generality of bulbous plants that one would find in any given locality in their native haunts would have devel- oped as offshoots of the bulb of an original plant or as inbred or close-bred. So the bulb has very fundamental importance in the plant economy. And it is interesting to reflect that it is correspond- ingly important from a human standpoint, inas- [104] ON THE TIGRIDIA much as bulbs furnish us some of our most important food products. We have seen that a good many of the plants that are propagated solely from the bulb or tuber, of which the potato is the most familiar example, may give up the habit of seed production alto- gether under cultivation. But, on the other hand, it is observed that plants that produce compara- tively small bulbs in the state of nature may be stimulated to the production of far larger bulbs and more abundant offshoots under cultivation. And the inherent reason for this is obvious when we consider the share the bulb must play in per- petuating a species and aiding it in the struggle for existence under widely varying conditions and in competition with other plants. Making application to the particular case of the tigridia, it has already been recorded that I have found no difficulty in doubling or even quad- rupling the bulk of the bulb of that plant, as well as greatly increasing the tendency to the multipli- cation of bulbs. I repeat that it will probably be found desirable to cultivate the plant further along these lines until it finds recognized place in the vegetable garden as the producer of a food of the finest quality, while at the same time retaining value as the bearer of beautiful flowers. [105] 03 J © to to C ^135 £ 3 .« •," « a fe • .2 § 'Z <=. « *.*Sc£ o to c J» l! <» R e "■3 OS £ 8a I V V I .1 ~ a p ° a 5 «T e § 3 © £ Si a a, p \> ^ *«■ Four Common Dooryard Flowers and Their Improvement Work on the Verbena, the Pink, the Petunia, and the Geranium MY most interesting verbena was the one named the Mayflower. I use the past tense because I am not sure that any rep- resentative of the variety named Mayflower is now in existence. I have introduced the plant through a prominent horticulturist, but he apparently found it difficult to reproduce it with sufficient rapidity from cuttings and so attempted to propagate it more rapidly from seed. Unfortunately the verbenas are so mixed a tribe, and the various races so little fixed, that they do not breed true from the seed. And so when I myself sent to the horticulturist for a sample of the fragrant Mayflower verbena a few years later, I received a plant that had but a reminiscence of the distinguishing quality of the original. In the meantime, however, I had developed [Volume X — Chapter IV] LUTHER BURBANK another race of fragrant verbenas, which was introduced in 1901 under the name of Elegance verbena. These are the two stocks from which a large number, at any rate, of the fragrant verbenas now under cultivation have been developed. My first fragrant verbena, the Mayflower, was developed after I had worked for many years with this flower and had grown great quantities of the seed for distribution. The plant from which the fragrant race was developed was found among many thousands, most of which, as is usual with the cultivated varieties, have a rather disagreeable odor. I had noticed, however, that there were mem- bers of the verbena colony that had a very slight fragrance, especially in the evening. So I began a careful search among them to find a plant the flowers of which had the most pronounced per- fume. After a long search among the thousands, I found at last a plant that was distinctly fragrant, markedly surpassing in this regard any of its associates. This individual was of course carefully isolated and its seeds were gathered. In due course I had a number of seedlings among which some were found that produced flowers more fragrant than those of the parent. The selection was con- [108] O «5 tj £•"3 a 3 6 2 c 9 £ N O* (t Vcttl I ill TO Q <. <* 5. js ?7a.ci 5 | « ~. w asa- 5 ~. a a a to" I'S.S s§ s: 2? ft > ~ » 5 <* a 5. S | •* £ *t s- b< ? a*™ a &*« P 3 £ a™ o to <3 a a •_ t Vx.3 e« eo a-«a CO a a LUTHER BURBANK tinued, according to my usual method, through successive generations, until at last a plant was found that is as fragrant as could be wished. The plant in question was an exceedingly large ver- bena— in fact one of the largest ever grown. The flowers it bore were of a rich rosy pink in color, the exact counterpart of the color of the familiar trailing arbutus or any flower of New England. Curiously enough the fragrance of the new verbena was also precisely that of the arbutus in quality, although it was much more intense, as was readily admitted by all who tested the two flowers side by side. It was for this reason that the new verbena was given the name of Mayflower. Several perfumers who saw this verbena were agreed that it would be of value for the produc- tion of a perfume. It was admitted by all that no verbena with a comparable odor had ever before been seen. The subsequent history of the Mayflower has already been told. It was purchased by a dealer, and although plants grown from cuttings made from it are probably in existence, I do not know where they are and do not know how to trace them. Aside from its fragrance, the Mayflower was an interesting type of verbena, owing to its size [110] ON FOUR DOORYARD FLOWERS and prolific bearing and the beauty of its flower. But seedlings grown from the plant could not be depended upon to produce flowers that would reproduce the Mayflower odor. Indeed they could not be depended on to reproduce any particular characteristic of the parent plant. In point of fact, seedlings of the Mayflower pro- duced plants bearing blossoms of almost every color — scarlet, crimson, almost pure white, yellow, deep cobalt blue, purplish. But not one of the many thousands I raised afterwards had the delightful flavor of the Mayflower. The Mayflower Accounted For As might be inferred from its variability, the fragrant verbena was a very mixed hybrid. It was the outcome of hybridizing experiments in which I had utilized the various races of the plant under cultivation. I had not only grown and crossed the ones that are in the seed catalogs, but also secured seeds from all four of the original species from which the cultivated verbenas have been developed, collected from wild plants in South America. It is quite unnecessary, however, to hybridize the verbenas in order to secure variation, as all of those that are under cultivation are themselves hybrids of very mixed strain, and the plant has been cultivated for a comparatively short period [111] * > k 3 **& S|S- *J « O J G e <»> is 4** 31 3 »> <« "~ £ 3 b — ft) 4) *- W r^fsj B ^> O 3 ^> •to 3 ON FOUR DOORYARD FLOWERS and none of the familiar forms breed true from the seed. The ancestors of the cultivated verbena were South American plants, and it is believed that there are four chief species that have been vari- ously hybridized to produce all the forms now under cultivation. One of these bears flowers of brilliant red, two others have flowers that are rosy or purple in color, and the flowers of the fourth are pure white. The hybridized races show the breaking up of these colors, quite as might be expected, with the presentation of all the primary colors in many of their hues and gradations, although pure blues are not well represented, and pure yellow is very exceptional. But the point of greatest interest in the present connection is the fact that the white species of wild verbena, which is acknowledged to be one of the forms, whose strains have been blended with the others to produce the cultivated verbena, has what is described as a rich jessamine fragrance. The hybridizing experiments that ultimately gave us the perfected verbena were carried out less than a century ago, but in the meantime the strains have been so mixed and blended that it would be impossible for the most part to trace the characteristics of any given form of cultivated ver- [113] LUTHER BURBANK bena with certainty. But it is obvious that the hybridizers and those who further developed the plant by selection were chiefly influenced by form and color, as has been the case with so many other flowers, and paid little attention to the question of fragrance. The verbena has been made to develop won- derfully symmetrical clusters, and its flowers have taken on the most gaudy hues. But in the main, as already pointed out, the odor even of the most beautiful specimens is disagreeable rather than attractive. Yet one of the wild parents, as we have just noted, was fragrant; and our previous studies of heredity give us full assurance that the factors for fragrance must be retained in some at least of the hybrid progeny, and will now and again make themselves manifest. That such is really the case, my fragrant verbena clearly enough demonstrates. To be sure its fragrance is not just that of the original. Some slight chemical modifications have taken place, doubtless through the blending of other chemicals that represent the odoriferous qualities of the other species, and it is only by rare exception that an individual appears having just the right combination to produce an attractive perfume. But the point of interest is that when such an [114] KftW 238, B M.« 2 3<© « <* a-&> ©--1. &•■« £. B -kg s"» <- 3"o S?3 .*5 S S" 3 g ;• ~- s "> 3 as » ST » » a re ~ o w eo 5 ■© S s ' 2"° 5. n°« ©• W 3< 3 3 m i ft i Q PA go 2.3 g § ~. S 3 c re © © «> re 3" CO ^ ft. <3- — s CO c LUTHER BURBANK individual does appear, as in the case of the May- flower and the later form named the Elegance, the anomaly is accounted for quite adequately by a knowledge of the existence of fragrant species among the ancestors of the hybrid. Even if we had no knowledge of the existence of such an ancestor, we should still be justified in assuming that a fragrant verbena is really a case of atavism. It will be recalled that we invoked the existence of remote unknown fragrant ances- tors in explanation of the appearance of our fra- grant calla. But there is an element of added in- terest in the knowledge that in the case of the verbena the ancestor responsible for the quality of fragrance can be traced. It would constitute a very interesting experi- ment in heredity, should someone care to under- take to hybridize a fragrant verbena with an odor- less one and to trace carefully the hereditary influ- ence of this quality — noting, for example, whether it acts as a prepotent or as a recessive character, and whether it tends to reappear in the second gen- eration in any fixed proportion of the progeny. It will probably be found that the condition that leads to the production of perfume of a par- ticular type is so complex and itself dependent upon so many factors that it is not inherited in any simple and readily traceable relation. [116] ON FOUR DOORYARD FLOWERS One of the distant relatives of the fragrant ver- bena is a fine shrub, worthy of introduction, known as the Alovsia citriodora. Another, as different as possible in appearance, is a little trailing plant known as Lippia repens. This little trailing plant is very valuable as a substitute for lawn grass. It requires less than one tenth the water required by blue grass, and only a fraction of the care. It need be sown only once or twice in a season, and throughout the sum- mer it will cover the lawn with a dense foliage, and bear a mass of small blossoms resembling those of white clover and fully as attractive to the bees. Unfortunately the lippia is not very hardy, and when the temperature goes much below freezing it turns to a disagreeable brownish color. Thus it is not adapted to the cold climates of the Northern United States. If it could be given hardiness through selection and cultivation, it would prove a very important acquisition for the making of lawns that will with- stand the summer drought. An allied species is the moss-like Verbena eri- moides, which is an exceedingly pretty plant grow- ing wild in the high Chilean mountains. In Cali- fornia it produces seed so abundantly and hence multiplies so rapidly that it becomes almost a [117] a 5 o CO * « I s © -. u 5 2 c 5 5?9=?=0'?>.rS i w v s ~ o ** Ss _, w a G» c «a a S § ft S 2 |is 2.8 » a s » "-*« ft g«5 3 §•«•& "^•^ 3 5 2. » » S 2 <» . 5. s'3 £-* o 5 o •on.2 a 2 B ^ K «£■* 5, >5°3 a ? 5 z. b • g §■* I b . "a 3 5* a o 3 a ty** 2 3 2 ° s 1 a ??Sk£ «~™~B f-. 5* o* ^(o §Ssn3 a b"S3*3 n "a o <» i 2". a b » Co S , CO ST 5' in ft LUTHER BURBANK tinguished from the geranium*, but which is obvi- ously closely related. An interesting story is told of the way in which the Pelargonium was introduced into cultivation. A physician, experiencing difficulty in obtaining plants from foreign countries and knowing that the seeds of many choice varieties often lie dor- mant in the soil, commissioned a sailor to bring him a barrel of soil from the Far East — I believe from Borneo. When the soil was received and spread out and cultivated, numerous plants sprang from it, among others the one that became the parent of the now greatly prized race of Pelargoniums. Whatever the truth of this anecdote, it at least illustrates a possible way of securing new plants from foreign countries. And however the Pelar- gonium was introduced, it has proved a plant worthy of the fullest recognition. It has, indeed, obtained such popularity that the old-fashioned types of geraniums have in many places lost their vogue. Hybridizing the geraniums is not at all difficult when one understands the process. It is only nec- essary to understand that the stigma of any given flower does not mature until after the pollen of the same flower has been scattered. Bearing this in mind nothing more is necessary than to gather [130] ON FOUR DOORYARD FLOWERS pollen and dust it on the stigmas of plants that have already shed their pollen. To make abso- lutely sure about guarding against the self-fertili- zation of the flower, it would of course be neces- sary to remove the stamens before ripening. Some of my experiments in hybridizing have been conducted with the idea of producing fra- grant races of geraniums. The chief difficulty in this work is that most of the fragrant geraniums have been grown for such a length of time from cuttings that they have for the most part lost the power of producing seeds. This makes it obvi- ously difficult to secure seeds from the plants that are precisely the ones it would be desirable to use for the purpose. Nevertheless I have produced a number of vari- eties having fragrance of very attractive quality. One of these fragrant varieties is developed from a compact growing Australian form which produces an enormous amount of seed. If this form were crossed with the other fragrant varie- ties a valuable type should be produced, as this plant has recently come from the wild and would instill vigor into the specialized and long cultivated plants. A line of work that I carried out at one time involved the crossing of the Pelargoniums with variegated leaves with those having ordinary green [131] J? s CO 6 R « S %» v> 3 i^.t; S m C a, ,5 B> © J) t. &J c 3 C ~ e « e a a »» "ti 's; ON FOUR DOORYARD FLOWERS leaves. Among these crossbreds it appeared that the green colored foliage was prepotent or dom- inant over the white and yellow variations. The horseshoe variations were more readily transmit- ted, but there was a varying proportion of marked and plain leaves among the hybrids. I also worked at one time in selecting the gera- niums for the production of large flowers of daz- zling brilliant scarlet color, and with a good meas- ure of success. One of the varieties thus produced has been greatly admired by all who have seen it, and will probably be thought worthy of introduc- tion. It will thus appear that there is abundant op- portunity for improving the geraniums even by working with the species ordinarily under culti- vation. I repeat, however, that the best oppor- tunity for work in this line will involve hybridizing experiments in which the exceedingly hardy wild species are utilized. It should be possible thus to produce new races of geraniums that have alto- gether exceptional quality. The wild species include some that are white in color as well as those that are pink or white striped with pink or with reddish veins. So there is opportunity to have a wide choice as to color variation. The cross might likely result also in giving the geraniums enhanced vigor so that new [133] LUTHER BURBANK races of perpetual bloomers comparable to the best of pelargoniums would be produced. Few plants among all the popular favorites have greater merits than the geraniums, and none, perhaps, offer better opportunities for interesting experi- ments that may be made by the amateur. — A plant which has been worked on by experimenters for two thousand years pre- sents a difficult problem for anyone who strives to develop new races of unusual value. It is like working against the traditions of the ages to attempt to modify the characteristics of such a plant in a new direction. The Everlasting Flower and Some Common Exotics The Australian Star-Flower and Plants from Orient and Tropics NOT long ago I received a tentative order for ten million clustered flowers in a single lot. The order came from a French mil- liner, who stated that unless he could get at least ten million blossoms he could not afford to handle them at all. I was too busy with other things to attempt to fill the order, but the fact that it was given is worthy of record as illustrating the more or less unexpected opportunities that open up before the plant experimenter. The flowers that the French milliner wished to use in such quantity are species of Composites known commonly as Everlastings. These flowers have long been popular because they retain their form and color more or less clearly when dried, and thus make permanent bouquets. In recent years, however, the abundance of fresh cut flow- ers has caused the everlastings to be much less popular than they formerly were. [Volume X — Chapter V] LUTHER BURBANK Now, however, it appears that a process has been perfected through which, by chemical treat- ment, the dried everlasting flowers are given a degree of permanency and toughness of fiber that makes them suitable for use in trimming hats. Moreover, the grace and beauty of the new Austra- lian star-flower are qualities not possessed by any other everlasting. Hence the milliner's desire to secure them in quantity. Although I could not undertake to meet so com- prehensive a request, I have nevertheless been ex- perimenting for a number of years with various tribes of everlastings. These are plants that orig- inally came from the Cape of Good Hope, and are hence known commonly as the Cape everlasting. There is an Australian star-flower that is pretty closely related, which is also an everlasting, and it is with this that my chief work has been done. This was sent me by my collector in West Aus- tralia, who first discovered it. With the more familiar tribes of everlastings I have been well acquainted since boyhood, but it is only in recent years that I have given them serious attention. They are of many colors — red, pink, crimson, yellow, orange, and white. Some of them that are annuals in the eastern states became per- ennials in California, even growing throughout the winter. The everlastings with which I have ex- [136] ft ~. 0" * •* B O* IT SHsSag, H "■a a i a "-•a §38 5 <* S a a 13 g* a a "* <» "* 2« a-~ a <* S _ ^ 3 a a 5 3 •a O "1 » u a » s, i "i S3S to g Co a a a i i »o? §^§ S3? a o a a *» 5' a 5* » ? a IS 11? 8 8-Ih a- *» * « c a* « San? B a,**? 5. a a, a S Q s* a a LUTHER BURBANK perimented most extensively belong to the genus Helipterum, and are known to the horticulturist as Rodanthes. My work commenced with a so-called double Rodanthes, which varies from white to red in color. The seeds that furnished the original stock were said to represent a double flower, but only a small proportion of the plants that grew from them bore flowers that were really double. That is to say, there was almost invariably a center devoid of petals. My work consisted in selecting to fill up the center, and make a flower that is altogether double. The flowers vary much in size, and the colors are so variant as to supply good material for selec- tion. But a difficulty arises in that the plants pro- duce very little seed. My selective experiments have now extended over a number of years, and I have been able to increase the size of the flower, to improve it considerably in the matter of double- ness, and to isolate to a certain extent the different colors, although the plant as yet is not fixed in any of these regards sufficiently to justify its introduc- tion. The improvement already shown, however, justifies the expectation that varieties of this ever- lastings could be developed that would show marked improvement over old types. I am experimenting also with everlasting flow- [138] ON SOME INTERESTING ALIENS ers of various other genera, including a Gono- hrena, the seed of which was received from South America. This plant has been under cultivation for many years. It is a low growing plant, having globular, crimson flowers. The introduction of new blood from the wild South American repre- sentative may be expected to have the usual stim- ulative effect, increasing the vitality of the plant, and perhaps urging it to greater variation. The Australian star-flower first mentioned in this chapter most resembles Rhodanthea, but is as distinct as a rose is from a carnation. The bot- anists have not been able to decide as to its specific name. With the exception of the Rhodanthea, this is without doubt the most beautiful of all the flow- ers called everlastings so far discovered or pro- duced. The beautiful star-shaped, rosy-crimson and white clusters of flowers, produced in the greatest abundance, are surpassingly beautiful. The plant is an annual, produced only from seed. The reason that this flower has not been more generally grown all over the world is that it is peculiarly subject to the attacks of soil fungi. On virgin soil it always thrives; on cultivated soil, sometimes. There is no doubt that this most beau- tiful of everlastings can finally become immune to fungi in cultivated soil through selection. My work with the Australian star-flower has [139] a «o ^ 76 § 4) *J 65. 3.Si ~ S.S3 O I. a. «- « «> ■g e*: < a. 5«2 ?^ a ■- ON SOME INTERESTING ALIENS consisted of increasing the size of the blossom, making it semi-double, giving it added brilliancy of color, and to some extent rendering it resistant to disease. This has been accomplished by the usual method of selection, strings being tied about the better specimens, and finally the one best being saved for seed. Very great improvement was made, considering that this was a wild plant never before under cultivation. The selected varieties do not as yet breed true from the seed. The Tribe of Crinums In an earlier chapter mention was made of hybridizing experiments in which certain mem- bers of the amaryllis tribe were crossed with cer- tain of the Crinums. It is desirable to make addi- tional reference to some experiments in which the crinums themselves were variously developed and hybridized with rather striking results. The hy- brid Crinums are a really splended group of bulbous flowering plants in which the bulbs are in many cases of enormous size, and the leaves are broad and long, making the plants very con- spicuous. Some of the leaves, indeed, are of gigantic size, and the stalk that bears the flowers may grow to a height of from four to six feet. The flowers themselves are of variant color, from white to rosy pink, and sometimes almost purple. They are [141] LUTHER BURBANK borne in profusion, and their attractiveness is often enhanced by their fragrance. The crinums were originally residents of the tropics, being indigenous to various parts of South America, the southern United States. There are several species that are hardy in California. In some cases they will withstand freezing, so that even if the leaves are destroyed by the frost the new growth will put forth in the spring, and they will bloom as abundantly as if they had been care- fully housed over winter. Like most other bulbous plants they thrive best in sandy soil. Some of the crinums are evergreen under ordi- nary temperature, others are deciduous like most of their relatives of the amaryllis tribe. The chief objection to the crinums for house culture is the enormous size of the bulb, and the tendency to produce a superabundance of foliage out of proportion to the number of flowers; al- though this criticism does not apply to all of them. Ten or twelve years ago I had probably twenty species of crinums, some of them having been brought from the tropics. My object was to com- bine the good qualities of the tropical and sub- tropical species with those of the hardy ones that had become acclimated in California. No diffi- culty was experienced in crossing the various spc- [142] A Burbank Crinum The crinum is an interesting member of the amaryllis family with which Mr. Burbank has performed a very large number of interesting experiments. Unfortunately the crinums are not very hardy, else they would be much more popular in our gardens than they are at present. LUTHER BURBANK cies, and hybridization was carried out in the usual way, different pairs of species being mated and then the hybrid forms in subsequent seasons re- mated, noting of course at all stages which com- binations seemed to produce the best results. Mixed hybrids were finally produced that com- bined the strains of many species. The results were highly interesting. In the course of a few years I had a strain of crossbred crinums presenting most of the desir- able qualities of the different species in combina- tion. The new plants, in spite of the strains of tropical species in their germ plasm, are very hardy, withstanding the coldest weather of this region without injury. They have very large flow- ers, varying in color from white, pink, and rosy crimson to purple. The petals are broad, and the flowers in a large number of cases are fragrant. The bulbs of some of these hybrids have taken on extraordinary growth. At four years of age some of them are from six to eight inches in diam- eter, and twelve to eighteen inches in length, weighing probably from ten to fifteen pounds, or even more. More recently specimens have ap- peared of even larger dimensions. Some of these enormous bulbs seldom make offsets, others pro- duce from one to twelve or more offsets in a sea- son, so that they can be multiplied quite rapidly. [144] ON SOME INTERESTING ALIENS The seedlings from these hybrids produce plants that as a rule show a combination of two or more of the species fairly well balanced. The seed parent of the larger number of my hybrids is the Crinum Americanum, but in some cases the Crinum amabale, or the Crinum Asiaticum was the seed parent. It is observed that a certain small percentage of the hybrids show a strong propensity to run toward the seed parent of whatever species. This can generally be detected by the foliage when the plants are quite small. I have not observed that any of the hybrids depart so strongly the other way toward the tropical species (the pollen parent). In the second and third generations the varia- tions are better balanced through selection, and become more fixed in desired qualities than at first, when grown from seed. On the whole, it is perhaps a little easier to get new species of crinums by crossing and selection than with most other bulbous plants, especially the lilies — although there are notable exceptions among the California lilies, some of which cross very readily. I have sold a number of the hybrid varieties of crinum, but they have been introduced unnamed, or at least were not named by me. The crinum seeds are very curious, in that they [145] An Improved Burbank Crinum This sturdy plan*, with its beautiful lily-like flowers, is an improved variety of crinum, developed by selective breeding. It is a flower meriting a place in any garden. ON SOME INTERESTING ALIENS vary enormously in size, almost always in the same capsule. The pale-greenish bulblike seeds with irregular corrugations may vary from the size of a pea to that of an English walnut. When placed in a graded sequence they present a curi- ous contrast. Yet the plants grown from the small- est seeds are likely to be quite as large and of the same appearance and quality as those grown from, the mammoth ones. The seeds of the crinum thus furnish a unique link between seeds, buds, and bulbs, suggesting the properties of all these combined. Another peculiarity of the seeds is that they contain so much nutriment and moisture that they may sprout and grow, making plants of consider- able size, without access to any moisture except that contained within the seed itself. I have known them to sprout when laid on a shelf, or in envelopes, away from the light and entirely dry; also when sent to me by mail from Australia they sometimes started as seeds and arrived here in envelopes as small growing plants. The crinums have been under cultivation for a long time, and interesting hybridizing experiments were made with them a century ago by the Rev. W. Herbert, Dean of Manchester, whose experi- ments with the glaaiolus and other flowers have been elsewhere referred to. But there are many [147] LUTHER BURBANK species that have not been so largely experimented with, and the opportunity to introduce new forms from the tropics, together with the striking char- acter of the plants themselves, gives them peculiar attractiveness for the experimenter. The possibil- ity of making still wider hybridizations, as in the case of the cross with the amaryllis, and further selections, should of course not be lost sight of. The Spectacular Ixia Another tribe of bulbous plants that have great interest is that represented by the genus ixia. These, like so many other of the interesting bul- bous plants, are natives of the Cape of Good Hope, and they are closely related to the gladiolus, and resemble many other Cape bulbs, including the Watsonias. There are various species, but they have been so intercrossed and mixed that the ex- perimenter need pay very little attention to specific names and distinctions. The bulbs are inexpen- sive, and are commonly grown several in a pot in the house in winter in the eastern states, but in California they grow outdoors, and there is no oc- casion to transplant them, except for propagation. A single bulb will spread by putting out new bulbs, which in turn make offshoots in the same way, until a large and beautiful clump of plants is often developed. The ixia, indeed, can never be seen at its best except when grown in this way. [148] Hybrid Crinum amnr,;,rUrban^ *"* hVbridi"d the crinum with the true 'SSia~= •saw. LUTHER BURBANK The flower stems are thrown up in great abun- dance on long, stiff, wiry stalks, and the graceful upright or drooping flowers are of every color except blue — crimson, yellow, and white being the characteristic colors. The variety of ixia known as the Wonder has double flowers that are exceptionally handsome. The group of ixias make so striking an appearance that they compete with the giant amaryllis in my gardens in May for first place in their appeal to the average visitor. The two plants are utterly different, but each in its way is most individual and striking; the ixia being characterized by gracefulness and fragile beauty, the other by its massiveness. The flowers of the ixia are only about two inches in diameter; those of the others eight to ten inches, yet the massed effect of the ixia is so striking that it com- petes in interest with the larger flower. I have worked in a more or less desultory way on the ixia for the past dozen or fifteen years. The varieties under cultivation are so mixed as to their ancestry, and hence have so strong an inherent tendency to variation that it is not necessary to cross them. Even the double variety is probably at least half a century old. My work of improve- ment looks to the increase in size and brilliancy of color of the flower; and, of course, here as [150] ON SOME INTERESTING ALIENS always, attention is paid to gracefulness and abun- dance of blooming, and vigor and general health of the plant. The improvements in all these regards have been quite striking, although I have not considered any individual variety worthy of introduction under a new name. Notwithstanding the amount of work that has been done with them, the ixias will well repay the attention of the amateur who cares to work with them. Oriental Poppies In an earlier chapter an account was given of my blue poppy. An account has also been given of the development of new colors in the flower usually called the California poppy, but more properly known by the somewhat forbidding name of Eschscholzia. Very little has been said, how- ever, about the experiments with the well known annual and perennial poppies, which have pro- duced some results of considerable interest. The poppies in question are the opium poppy (Papaver somnifera), and one previously called the Oriental (Papaver orientalis) . The opium poppy is, as everyone knows, a commercial product of vast commercial impor- tance in the Far East. It has been under cultivation in Europe to a greater or less extent for several [151] Seed Pods of the Crinum The seeds of the crinum show an extraordinary range of variation, some of them being small, whereas others are so large as to suggest miniature bulbs. The latter are so succulent that sometimes they sprout when lying on the shelf. On one or two occasions Mr. Burbank has had crinum seeds sent from a distance by mail, which sprouted en route. This is an interesting and very unusual peculiarity. ON SOME INTERESTING ALIENS centuries, and has been greatly improved by the European growers, the varieties developed being of almost every shade of color, some flowers being single and others double. From time to time charming varieties have been sent out in recent years, including an interesting single one known as the Miss Sherwood, a variety having blossoms with a white center and crim- son edge, the petals being beautifully fringed. There are other varieties known as Paeonia and Carnation Flower poppies that are double and are exceedingly handsome in color. The Oriental poppy has very large flowers, always crimson with shadings of scarlet in color in a state of nature, and in almost all cultivated varieties — the color being unusually well fixed. The plant is a perennial with rough, hairy leaves. The flowers are borne on single stems, instead of branching from a main stalk as in the opium and most other poppies. The Oriental species has probably not been under cultivation as long as the other, but many varieties have been developed, some of them semi-double, and the colors have been modified so that there are dull white, scar- let, and yellowish varieties, as well as the more usual crimson. These varieties, however, seem not to be well fixed — they do not come true from the seed — and [153] LUTHER BURBANK the best varieties so far produced quite generally appear to be lacking in vitality — possibly from overzealousness in selection by division, the only way of maintaining and multiplying any special variety. My own experiments have largely had to do with hybridizing the Oriental and the opium poppies. Rather curiously I found that the pollen of the opium poppy was ineffective when used on the Oriental, yet when a reciprocal cross was effected, the pollen of the Oriental being used on the opium poppy, seed was produced, and a great number of hybrids were soon under observation. In the hybrid colony, comprising more than thirty thousand of these plants, there was as little variation in color as is usual with the Oriental poppy. None of the hybrids were double, but they had several interesting qualities. One striking peculiarity was that the hybrid poppies produced in some cases enormous seed capsules, five or six times as large as the ordinary seed capsule of either parent species. Yet in other plants the seed capsule would be smaller than that of either parent. In still other cases twin capsules are produced uniformly, and with a certain num- ber there was produced a mere rudiment of a capsule. But the most striking of all were the [154] * *>** Chinese Opium Poppies This is a variety of the flower, from the seed heads of which the familiar commercial drug, opium, is extracted. Mr. Burbank has experimented extensively with this as with many other species of poppies, though not, of course, with refer- ence to its opium-producing qualities. LUTHER BURBANK numerous plants that produced not even an inti- mation of a capsule, the flowering stem ending abruptly like the end of a lead pencil. All in all the hybrids showing this extraordi- nary variation in the seed bearing capsule — rang- ing from enormous enlargement of the capsule to its entire obliteration — make a very wonderful and interesting study in heredity. It is of further interest to note that, although these hybrids were raised from seed of an annual poppy (hybridized, however, by a perennial), yet without exception every member of the entire company of thirty thousand is a perennial. The flowers, themselves, vary greatly in size, some of them being seven or even eight inches in diameter, while the smallest are perhaps only four or five inches. Some are beautifully crimped, others have flat petals, there being the most strik- ing variations in form. Even the specimens that have unusually large, plump seed capsules may produce no thoroughly well developed seeds. In a gallon of the seed- pods, from which one might expect perhaps two quarts of plump seed, I usually obtain perhaps from one hundred to three hundred or four hun- dred grains, mostly of shrunken ill-shaped seeds. Yet these shriveled seeds when sown produce good plants. Even seeds that seem so abortive that it is [156] Another Specimen of the Chinese Opium Poppy It is probable that the Chinese opium poppg represents the result of careful selective breeding on the part of unknown plant developers. But the development of its drug-bearing qualities has not interfered with the beautg of the flower, as is evident from a glance at the specimen here shown. LUTHER BURBANK incredible they should germinate, may produce perfectly healthy seedlings. Striking Variations in the Second Generation The second generation poppies produced from these seeds were among the most remarkable com- panies of plants that I have ever seen. All who saw them agreed that they were the most variable lot of plants of a single fraternity that they had ever observed. The diversity was so great that it might be said that there were no two plants among the thousands that were even approximately identical. No two could be found in which differences could not readily be observed in the foliage. Some of the peculiar forms of leaf were these : (1) Long, smooth strap-shaped leaves sometimes not more than half an inch wide and a foot or more in length; sometimes smooth and sometimes villous; dark green or light green. (2) Short and stubby leaves, trifoliate, either villous or glaucous. (3) Leaves resembling those of the Oriental poppy. (4) Leaves like those of the opium poppy. (5) Nondescript leaves, variously suggestive of the leaves of primrose, cherry, dock, wormwood, dan- delion, and scores of others. It is interesting to note that the blossoms of the second generation varied somewhat less than the leaves, although much more diversified than [158] A Hybrid Poppy Mr, Burbank's experiments tn hybridizing the poppies are of exceeding interest. Here is a specimen of a cross be- tween the opium poppy and the oriental poppy. The anomalous re- sults of this combination, of great interest to students of heredity, are related in the text. LUTHER BURBANK the blossoms of the first generation. Some were double and of various shades of the opium poppy. The range of color included almost black, deep crimson, purple, light crimson, salmon shades, pink, white, and various combinations of these col- ors. Yet on the whole the color variation was not greater than that ordinarily found in the opium poppy. The second-generation plants seemed not to have the vitality shown by those of the first gen- eration. There were exceptions to this, however, individual plants manifesting a vitality in excess of the average of the first-generation plants. Most of the second-generation hybrids that pro- duced double blossoms proved to be annuals or biennials, partaking thus of the characteristic of the parent from which they derived their double- ness of blossom. This is perhaps what might have been expected. It is notable, however, that the quality of annual or biennial growth should have reappeared in these hybrids of the second genera- tion, the first generation hybrids having been, as already noted, ail perennials. But, on the other hand, some of the second generation hybrids were perennials, and have con- tinued to live and thrive, bearing large quantities of blossoms each season. Thus the perennial and annual habit appeared, [160] Giant Oriental Poppy The selected poppies sometimes attain very extraordinary size. This blossom measured almost a foot across. Few flowers afford greater interest for the amateur gardener than this spectacular visitor from the orient. o C3 05 "5. 1 ft- ? E3 o, « : n © O, ^ t, o », u « © -K, J- 2«~ *i 2= « •- %> b -•» fi fee S c £ *~ 4> O a a « 2 ° o> a. - 2 "5 *b * ■„*£ IS a c «j a. a, 52 3 ». «>&3 s a ON SOME INTERESTING ALIENS in the case of these two poppies, to be a pair of unit characters of which the perennial habit was dominant and the annual habit recessive; there being a characteristic segregation in the second generation. As to habit of blooming, there was another in- teresting anomaly. The opium poppy, a strict annual, blossoms only for a short period — for a few weeks at most. The Oriental poppy, although a perennial, also blooms but a short time. The first generation hybrid poppies bloom persistently. There is not a day in the year when some of these hybrids are not in bloom, spring, summer, autumn, or winter — blossoms can always be gathered in quantity from them. The hardiness of the hybrids has not been fully tested. I should not be surprised to find that they are largely as hardy as the Oriental poppy, but the California climate does not subject them to a severe test. The Third Generation Hybrids In the third generation, a large number of the hybrids reverted toward one or the other of the original parents. But even those that resembled one of the parents or the other strikingly, retained also traits of the other parent. In this generation the plants mostly produced no seed, and the tribe partially ran out. [163] c w o *! i *> "" h y a oh*; a o a e 5 *^s s is <2 ©£ S3 » 3 ■a ag~ s ° «\ ~ 3 a a o. a a o> rr c « " "E A ,_ 2 « « « a A c c a i ; i ; s L. H S a . a a a 4i »- J4 a a a a a a ON SOME INTERESTING ALIENS All these unique hybrids present such interest- ing characteristics that it will be worth while to record that the opkim poppy that was used as the original parent was of the Miss Sherwood variety, but that later other opium poppies of every shade and color that could be obtained were also used. Perhaps in all twenty-five or thirty selected varie- ties of opium poppies of various colors and differ- ent forms were used as seed parents. The progeny, however, as far as I could observe, varied little and was not greatly influenced by the different type of opium poppy used. However, the varia- tion was so great in any event that it would be difficult to judge as to this. In general, the minor colorings and doublings of color seemed to have less effect in the heredity than the more fixed original foliage and flowers of the wild plants. The hybrids show doubleness and selected colors very slightly, except in a few cases in the second generation, when there was a tendency to return toward the original forms. It should be noted also that the Oriental poppy, al- though failing of fertilization when treated with pollen of the opium poppy, produced seeds abun- dantly when fertilized with its own pollen. The size of the pollen and length of the pollen tubes may conceivably have something to do with the failure to effect hybridization when the Ori- [165] LUTHER BURBANK ental poppy was used as the pistillate parent; but this is only conjectural. Also, the opium poppy has been so long under cultivation, and has become so adaptable, that it perhaps is more pliable and more ready to receive strange pollen. The relative sterility of the first-generation hybrids may be judged from the fact that almost five thousand seedlings produced ten or twelve gal- lons of capsules, but that there was only about a quarter of a teaspoonful of seed to each gallon of capsules. As these seeds were shrunken and much smaller than ordinary poppy seeds, however, the actual number of seeds was proportionately large. Still the total number was only a fraction of what would have been the output of poppy plants of normal fertility. All in all, this experiment of hybridizing the Oriental and the opium poppies, with the produc- tion of relatively infertile hybrids showing Mende- lian heredity as to some traits and a blending of characters as to others, and a further segregation and recombination of characters in the second generation, constitutes an unusually interesting experiment in heredity. I have made many other experiments in breeding the various poppies, but none perhaps that excelled this one in interest and importance. [166] The Hybrid Larkspur— and Other Transformations Introducing a Miscellaneous Company THE members of my larkspur colony are all descended from a single individual. That individual, in turn, was the select and peerless member of a company of five thou- sand, all of them of equally aristocratic lineage, and each one of them worthy to show itself in any larkspur company. But the usual rigorous method of selection was applied to them. The one individual that came nearest meeting all expectations was preserved. The rest were sent, with sundry thousands other plants of divers species, to the bonfire. The selected individual, of course, became the progenitor of a new colony of larkspurs. Some of these improved upon their ancestor, and among them several interesting varieties were isolated through selection. The original parent form from which the one [Volume X — Chapter VI] LUTHER BURBANK best larkspur was selected as the progenitor of new races was of the species known as Delphinium hybridum, or hybrid larkspur. As the name im- plies, this plant is itself of hybrid origin, but it has been cultivated a long time in Europe, being unus- ually popular in England, and ranks as a true species, or at least as a good horticultural variety. There are numerous other species of larkspur, sixty or more altogether. Some are annuals and some perennials. Our native California species are among the most beautiful. One of these, named nudicaule, is a perennial growing along the sides of streams and in shady canons, although on occasion even mounting to the tops of high rocks. It bears flowers of a bright orange red, sometimes varying to yellowish, that are very showy. The plant is easily cultivated either from seed or by division, as indeed are all perennial larkspurs. Another species is D. cardinale, a large, strong plant, growing in the southern part of California, the flowers of which are also bright red and yellow though quite different in general appearance from those of the one just named. Yet another larkspur that is of interest is the D. decorum, an extremely variable form growing usually on overflowed land. The flowers of this wild species vary almost as much as do our hybridized and cultivated ones. [168] Improved Hybrid Larkspur Few of Mr. Burbank's flower productions are more pop- ular than his improved hybrid larkspur. This picture suggests that the flowers amply justify their popularity. They are the product of hybridization, as their name suggests, combined with careful selective breeding. LUTHER BURBANK Growing side by side in a bed of wild larkspurs of this species may be found plants bearing flowers varying from deep blue, pale blue, dark rosy pink, pale pink, and yellow, to almost pure white. The flowers of these are quite large and showy, but the colors, although so variant, are seldom brilliant. The larkspur known as D. Calif ornica is a giant species, often found in canons toward the coast. For a larkspur it towers to a great height, some- times reaching seven or eight feet, but the flower is insignificant when compared with most other varieties both in size and color. They are purplish blue or dingy white in color. My attempts to cross this species with some of our cultivated ones have not resulted in producing anything of value. Still another species is known as D. hespirium. It grows in sandy or heavy black soil as the case may be; is about two feet in height, and bears flow- ers that are almost invariably of deepest blue, although sometimes pink, pale blue, and white ones are found. These wild species are mentioned somewhat in detail, chiefly to show the variation among them, suggesting the possibility of interesting develop- ments when the various forms are combined. I have utilized them all more or less in experiments, and in addition have grown nearly all the lark- [170] ON SOME FAMILIAR COMPOSITES spurs that are ever offered by seedsmen or florists. As already stated, my chief experiments began with the use of the hybrid larkspur as a seed par- ent, but of course the hybridizing experiments soon blended the strains of many of the other spe- cies, until the larkspur colony, like so many others of flower groups, is of such conglomerate ancestry that the precise proportions of the different strains in any given race are not traceable. Needless to say, selection has been carried for- ward along with the hybridizing experiments, these two methods always being complementary. Particular attention has been given to size of flower, vigor of plants, and resistance to insects and disease, as well as that of multiplication by division, at the same time that compactness of growth and brilliancy of color of flower have been carefully regarded. One of the worst faults of the larkspur is that it tends to grow too tall, with a stalk that does not support it, so that it requires to be staked. But my hybrid larkspurs have been so selected that they are compact in growth, and able to support themselves even in a moderate gale. All the characteristic larkspur colors are rep- resented among the new varieties, and in addition there are combinations of color that have never before been seen, I think, in the larkspur. Some [171] Color Variations in Hybrid Larkspurs The hybrid larkspurs are very pleasing in form, and the compact clusters in which they grow are peculiarly attractive. But their other good qualities are enhanced by the wide range of color variation, of which a suggestion is given in this picture. The range of colors is striking, and all of the colors are pleasing. ON SOME FAMILIAR COMPOSITES of the individual flowers are considerably over two inches in diameter, and some of the largest are very double. The color yellow is not usual with the larkspur, its characteristic colors being red, blue, and white. There is one yellow species, a native of southern Asia. I have, however, developed varieties with pale yellow flowers. The best of the selected varie- ties, as descended from the original one chosen among the first five thousand, is known as Bur- bank's hybrid, and has been given full recognition by seedsmen, florists, and gardeners. There is still opportunity for further development among the larkspurs, however, and improvements may be expected which, if not spectacular, have at least a fair measure of interest. No plant is ever so fully developed that it does not hold possibilities of improvement. An Almost Endless Variety The great family of composites presents an almost endless variety of flowers, of which we have seen some striking examples, most notable among these being perhaps the daisies and the dahlias. But now and again a new form makes bid for pop- ularity, and there is still an indefinite amount of material among our wild plants from which gar- den plants might be developed. Yet the old favorites are not necessarily sup- [173] LUTHER BURBANK planted. Indeed there are some of them that have perennial interest, holding their charm despite all competition. One of these is the marigold, of which there are various species that find favor not only because of the ease with which they may be cultivated, but also because of the length of time during which they bloom, the abundance of blossoms, and their good keeping qualities after being picked. The marigolds most commonly cultivated fall into two distinct groups, one spoken of as the Afri- can marigold and the other as the French mari- gold. In addition to these there are native species, among others a very interesting one that I have received from Arizona, sent me by Professor Lemon, whose name it bears. This native form is a shrub about four feet in height, and in the fall it bears a mass of beautiful single golden flowers about the size of the French marigold. This is one of the handsomest shrubs of this sort, and although I think it has not yet been intro- duced, it deserves a place in every garden, if — as has not yet been proved — it will stand the colder climate. My experiments with the marigold were con- ducted a good many years ago, chiefly along the line of crossing the French and African races and this new Arizona perennial species. In addition [174] A Brilliant Specimen This is one of the most brilliant of the hybrid larkspurs M i £ a vaTi^V/^tin9nished also by the large size of its flowers and the wonderfully compact and symmetrical clusters. A flower like this is a treasure in any garden. LUTHER BURBANK to their practical horticultural results, the experi- ments gave some interesting illustrations of heredi- tary influence. In particular I observed that when the double marigolds were crossed with the perennial single species above mentioned all the hybrids were single. Moreover, if I am not mistaken, they were all annuals, though the perennial marigold was the mother plant in every case. It is interesting to recall that precisely the op- posite result was produced in hybridizing the pop- pies. In that case the union of an annual and a perennial poppy produced hybrids all of which were perennials. One of the best marigolds with which I have worked is called the lemonball. It is of the African type, and it produces great lemon-yellow blossoms in abundance, blooming throughout the entire sea- son. The best specimens are thoroughly double, but if the seed is saved from the most double blos- soms, almost half of the seedling will bear single flowers or those not perfectly double. It is obvious that the factors for singleness and doubleness tend to be segregated, and that the strains of the double marigold have not all been isolated in such a way as to produce germ plasm that is unmixed as regards the factors for number of petals. [176] A Distinctive Cluster It is difficult to see how this hybrid larkspur could be improved upon as to the symmetrical development of its flower cluster, and the uniformity and excellence of its individual blossoms, nearly all of which, it will be seen, are in full bloom at the same time. But in point of fact there are almost numberless varieties of equal merit among Mr. Burbank's hybrid larkspurs. LUTHER BURBANK Presumably this could be done by careful selec- tion. My more recent experiments have to do with the general improvement of the marigolds, ana I am also experimenting with a new species from Chile with reference to its possible value as a pot- herb for its fragrance and flavor. It is a tall, slen- der shrub with innumerable pale, straw-yellow flowers — almost white. Like one or two other spe- cies of the genus it has a most delightful fragrance and flavor. As regards quality and intensity of flavor, it surpasses all others, but it apparently has no other merit. Whether it will prove of sufficient value for introduction in the vegetable garden is still problematical. A much less familiar member of the composite family which, however, has gained rapidly in pop- ularity in recent years is the plant known as cos- mos. This is a Mexican species that is now making its way into the flower gardens everywhere. It is related to the plant known as the black dahlia (Bidens astrosanguinea) botanically, yet the rela- tionship is not so close that the two can be com- bined, at least I have not been able to effect crossing between them. A peculiarity of the cosmos, due doubtless to its recent importation from a sub-tropical region, is its habit of blooming very late in the autumn. [178] A Flower Cluster of Many Colors Here is a bunch of hybrid larkspurs combining delicate yellows, pinks, and blues. It would be an interesting experi- ment to take the seeds of this single flower head, and endeavor to produce, by selective breeding, varieties of larkspur having flowers of uniform yellow and pink and blue re- spectfully. Such possibilities as this are open to any one who wishes to experiment with this inter- esting flower. LUTHER BURBANK This is sometimes regarded as a merit, but as the plant is very tender, there is danger that its blos- soms will be blighted by the early frosts. So the most important work that has been done with the plant in recent years is the production of early blooming varieties. The effort has been so far suc- cessful that there are now varieties that bloom in midsummer. The fact that this modification has been brought about within a comparatively few plant generations illustrates the pliability of the cosmos. It is, in point of fact, one of the most variable and pliable of plants — comparable in this regard to the dahlia. Such being the case, it is not surprising that it has been found possible to develop new shades of color, as well as much larger and finer flowers than those of the original species. Forms with wider petals, and others with twisted petals and other variations of the corolla, have also been developed. Even a double cosmos has been mentioned as forthcoming. But the plant is comparatively new in the flower garden, and it offers therefore rather exceptional opportunities for the experimenter. The amateur who is looking for a plant that has not been carried to anything like its limits of variation may advantageously pay attention to this graceful, attractive, and rapid-growing composite. [180] ON SOME FAMILIAR COMPOSITES The extreme heat and long days of the summer even in high altitudes in the United States makes possible the cultivation of a large number of flow- ers that were originally of tropical habitat. Among these no others are more familiar or have retained their popularity more steadily than the tribe of plants of the genus Iponoea, which numbers among its representatives plants of such diversity as the morning-glory, the moon-flower, the cypress vine, the yam, and the sweet potato. The Brilliant Morning Glory It is not difficult to account for the popularity of the morning-glory. A vine that grows with the greatest rapidity and that bears flowers of striking and brilliant color in the greatest profusion, day after day, for weeks together, covering our arbors or pergolas in a few weeks' time, has merits that are not duplicated exactly by those of any other flower under cultivation. The morning-glory has not been very exten- sively worked with, but it has shown a marked tendency to variation, and, as usual with plants under cultivation, has broken up into numerous varieties, showing in particular a wide range of color variation. One of the most remarkable of the varieties is the Japanese morning-glory, some forms of which have double flowers of very curi- ous structure. The single varieties of the Japanese [181] More Hybrid Larkspur Variations Compare this cluster of hybrid larkspurs with those shown in earlier pictures and in the succeeding one. After making such a comparison, no one will need to be told why the hybrid larkspur is an exceedingly popular flower, — particularly when it is recalled that, in addition to its other merits, this is a peculiarly hardy, thrifty, and prolific bearer. ON SOME FAMILIAR COMPOSITES type are of relatively immense size and of the most wonderful color. But they do not produce so abun- dantly as the common morning-glory, they do not climb as well, and they seem to lack the vigor of the ordinary form. My experiments with the tribe have had to do with the crossing of several related forms. The plants can generally quite readily be crossed, and the seed germinates readily. These experiments have not been carried far enough to produce any very striking results. It is obvious, however, that the morning-glory offers good op- portunities for improvement, and the ease with which it can be cultivated makes it a plant that should appeal particularly to the amateur. The wide range of color variation, together with the fact that the colors are fairly fixed in certain varie- ties, make possible crossbreeding experiments that can readily be checked. Possibly also it may be feasible to cross the morning-glory with the moon-flower or with vari- ous other members of the genus. The moon-flower itself, which produces large white flowers in great abundance, has been greatly improved by selec- tion. There is also an interesting Brazilian morning- glory (Ipnoea setosa) with a vine that grows with great rapidity and bears a rosy purplish flower, [183] Variable Clusters These specimens of hybrid larkspur are selected as sug- gesting the considerable range of variation in the make-up of the clusters of blossoms. Note the very striking contrast between the cluster at the left and that at the right, the latter being the re- sult of a long series of experiments in careful selective breeding. Compare this picture with earlier ones of this series, to suggest the full range of variation in form and color among the selected hybrid larkspur. ON SOME FAMILIAR COMPOSITES and a perennial tree morning-glory, a native of Texas, which bears very large light pink flowers in abundance. Indeed the number of species from which selection can be made is rather large, and variation among them sufficient to give the experi- ment in hybridizing exceptional interest. Another vine-like plant from South America that has made its way into every garden is the Tropaeolum, commonly known as the nasturtium. There are at least forty species of this tribe, mostly climbing natives of Peru and Chile. One of these, T. puberosum, produces spicy roots that are highly prized as foods, and its seeds are some- times used in salads under the name of Indian cress. The seeds of the form familiar in our gar- dens are sometimes pickled, and it is probable that table products of greater value could be developed from these plants if attention were paid to breed- ing them with that idea in mind. Some of the nasturtiums are exceedingly tender to the slightest chill, but they may grow in the hottest and driest soil. My work with the nasturtiums has been done with specimens sent from South America by my collectors, representing eight or nine species. Some of these have bulbs that remain dormant in the ground for two or three years, and then sprout and grow very fine vines that climb over the bushes. [185] LUTHER BURBANK The common nasturtium of our gardens, T. majus, is one of the most readily grown of our annuals and has been so long cultivated and so thoroughly crossed that the colors of the flowers are exceedingly variable. In recent years very good work has been done, particularly by Cali- fornia cultivators, in the improvement of the climbing nasturtiums, and in particular by cross- ing the ordinary form with the one known as T. minus. Both the parent forms and the hybrids have run into numberless colors, clear lemon yellow, flesh color, deep crimson, purple, scarlet, deep yellow and white, the colors being variously blended, and the foliage of the plant being sometimes most beautifully variegated. Even the form of the leaf has been changed, so that there now are ivy-leaved strains of nasturtiums. The nasturtiums offer great interest for the amateur experimenter, as they are very readily hybridized, and as their range of variation, even without crossing, is so great as to afford the widest opportunity for selection. Indeed, crossing has been so fully carried out that for ordinary purposes selection will answer far better than further cross- ing. Indeed it is exceedingly difficult to keep the colors of the various nasturtiums separate. The seed of a pure white variety quite commonly may [186] California Morning Glory This is one of numerous species and varieties of morning glory utilized by Mr. Burbank in his experiments with this flower. As some of the species come from the tropics, there is oppor- tunity for the blending of widely different heredities. LUTHER BURBANK produce various colors. And it is more difficult to fix these colors than is the case with most other flowers. But of course such difficulties only en- hance the interest of a really earnest experimenter, and develop his enthusiasm. Stamping Personality on a Flower An illustration of the way in which the person- ality of the experimenter finds expression in the plants that he cultivates was furnished me a num- ber of years ago by Mr. Peter Barr, a well-known horticulturist who specialized with the narcissus and daffodils. On visiting my place a number of years ago, he related an experience that may be taken as typical, yet which the amateur who has not experimented extensively might regard as rather extraordinary. The story has been told in an earlier volume, but it may be briefly repeated here. Mr. Barr stated that among the thousands of seedlings the whole stock of which he purchased of two specialists in England, he could always tell at once, on seeing the blooms, which of the two specialists had developed any individual plant, even though the varieties had been mixed. One of the breeders produced very large, coarse flowers, gigantic and broad, and lacking in delicacy of contour. The other produced seedlings of graceful and exquisite form. [188] A Bed of Hybrid Morning Glories Here are some of Mr. Burbank's hybrid morning glories, showing the not unusual propensity of hybrids to grow luxur- iantly and bear flowers in profusion. This vine represents a stage of progress, rather than the completed product. LUTHER BURBANK And these contrasting characteristics of the different daffodils, Mr. Barr assured me, typified the personalities of the two breeders by whom they were developed. One of these was a person of little refinement, notwithstanding his love of flowers; the other was a cultivated banker of artistic temperament. The tastes and propensities of the two men made themselves felt in all the flowers they produced; which of course was inev- itable, when we reflect that the plants were pro- duced by selection, and that each man naturally selected the type that appealed to him. I cite the incident not as something exceptional, but as typical. Almost as a matter of course, one could draw correct inferences as to the personality of a plant developer from observation of the varie- ties that he has developed — provided always, of course, that his selections have been made along the line of his own tastes, and not to meet some specific commercial demand. There should be for the amateur an added stimulus in the reflection that he is thus putting the stamp of his own personality upon the plants with which he experiments. The flowers of your own garden may thus come to have an individu- ality that represents you as fully as you are repre- sented by your costume or by the books you gather on your shelves. And surely the possibility of [190] ON SOME FAMILIAR COMPOSITES developing a flower garden that has such individ- uality, differing from any and every other flower garden in the world, should give the pursuit of the amateur florist unique interest. Some Interesting Natives I have more than once suggested the possibility of introducing to the garden species of plants that grow in the wilds and that offer interesting possi- bilities of development. Two or three other tribes of these interesting wildlings may be here referred to. To name all that are worthy of consideration would take many volumes for there are more than ten thousand species of flowers indigenous to the United States, and of these only something like fifteen hundred have at one time or another been placed under cultivation. I may name two or three familiar ones, in addi- tion to those that have already been referred to, as offering exceptional attractions. There are, for example, the Gilias, represented by many species. I have cultivated twenty or more wild ones at one time, selecting for brilliancy of color, for size of flower, for compactness of growth, or for some other desired quality. On occasion I have carefully scrutinized at least ten thousand different plants in order to select the individual with which to begin improvements. The gilias vary greatly in color, so that they are [191] A New Burbank Morning Glory Quantity production again, with ample opportunity for selection, that the very best hereditary possibilities of the hybrid may be revealed. The variety here shown is one of the newest developments at Santa Rosa, as the morning glory experiments are still in progress. ON SOME FAMILIAR COMPOSITES very interesting flowers with which to work, and the colors may very readily be fixed in the course of four or five generations. So also may the quali- ties of compact growing, size of flower, and the like. The plants, therefore, are encouraging ones for the amateur who is anxious to get results. The familiar milkweeds have been referred to in another connection with reference to the pecu- liar arrangement of their pollen masses, which are so adjusted as to entangle the feet of bees. The amateur will find it peculiarly interesting to cross-pollenize these flowers. It will be ad- vantageous to work with a magnifying lens of con- siderable power. The curious form of the flower and the unique arrangement of the pollen masses give the work of cross-fertilizing these plants a unique character, and these flowers are in general among the most puzzling of all flowers for the amateur. There is possibility of developing, among the milkweeds, plants of commercial value. I have worked somewhat extensively with a number of unclassified South American species. For two or three years I carried on the work of selecting the best seedlings among a large number, until several races were pretty sharply defined. Now I am crossing the best of these, the object being to get varieties of more beautiful blossoms for garden [193] LUTHER BURBANK culture, and also to secure varieties that will be of value in producing a fiber that has something of the quality of silk. Even now tons of milkweed seed pods just before they are ready to open are dried in the Mis- sissippi Valley and shipped to Japan, where they are used to make a kind of felt. In the Philippines there is an allied plant, the Kapok, which supplies a fiber much used for filling pillows and the like. It is considered within the possibilities that a variety may be produced that will be of value for the production of rubber, as the juice of some species has excellent rubber qualities. The native varieties of milkweed are exceed- ingly hardy and as they are perennials they may be worked on season after season. There is great variation as to vigor of growth, size of leaves, com- pactness of plants, and color and form of leaves, as well as regarding the size, color, and abundance of blossoms. The seed pods, with their white, silk- like fiber also vary greatly. And there is corre- sponding variation as to the amount of latex or milk produced by the stalks. All in all, then, there is scarcely another tribe of plants that shows a wider range of interesting qualities for observation of the experimenter. Another wildling offering attractions of a dif- ferent character is the so-called painted cup, or [194] 5 TO ft "i a. s?:;?s?«'??!!>: m 3 ?S TO ■ ~- Q -*8 ~>g TO^* "« ™ 2. S "a » 5> »9„." §•3 III &•». 'SS», c a s ^ssv -S3 *■* £* 5 TO D :s to § 5. * *f» £"5 n. » ~ ET 8 to a.S.re«< S.8 g« - S- S f 3 3 $£»&§ ^ a a ^ ***■ ?S £2.7- S a •» :** © TO 8* X TO ~k , TO 8 S a « 3 9 S o » q ^* TO « &2 TO TO & o a. Sr to LUTHER BURBANK Indian's paint-brush, classified by the botanist as Castilleia. The most familiar form of this plant is the one known for its brilliant scarlet color. But the tribe is exceedingly variable, and the different members present flowers that range from scarlet, crimson, orange, yellow, and purple to pure white. Some are variegated. Individual plants of the first named species growing on the same cliff along the shore may show the widest range of variation in the color of their blossoms. Indeed, all colors are sometimes combined in the flowers of a single plant. In other cases one will find a small patch of yellow flowers in one place, and in the neighbor- hood another patch of orange colored or of white ones. The only color that is missing is blue. It would thus be an interesting quest for some plant devel- oper to see whether he could develop a blue painted cup, somewhat as I was able to develop a blue poppy. Even failing in this, the opportunity to study heredity of color, and to isolate races of painted cup of one color or another, attempting to fix them so that they would come true from seed, would give recreation for a number of seasons. The fact that the painted cup does not always prove easy of cultivation suggests that it is a plant [196] ON SOME FAMILIAR COMPOSITES worthy the attention not merely of the beginner but also of the amateur who has gained a measure of experience, and who is willing to try his hand at problems of plant development that are not free from difficulties. As I said before, it would be possible to extend almost indefinitely this list of interesting flowers that invite development. But the ones named may serve by way of introduction, and the amateur may readily extend the list by looking about in almost any garden or by rambling almost anywhere along country roads or in neighboring fields. — The material lies everywhere about us, and despite the activi- ties of large numbers of flower lovers, there are hundreds of species readily accessible that have never come under the hand of the cultivator, and which therefore have the attraction of entire novelty. ATSH*! •3 £S 2 Oh 3- -»^ s^IsS" © ~ c c * b 5 9 5 .c ? 13 « ° E . 9 ■"• 5 ■« !)•" 5 »1 £ .2 e g = = Ornamental Palms and Climbing Vines Views on Artistic Treatment VISITORS from the East are often surprised to find palms growing thriftily at Santa Rosa. The average resident of northern latitudes appears to associate the palm with trop- ical conditions. And while it is known to everyone that these trees grow in Southern California, it seems a matter for wonderment that they should be found so far to the north as the region in which my experiment gardens are located. In point of fact, isothermal lines make no dif- ference in California, as the winds from the Pacific, deflected by the mountains, determine the climatic conditions, and produce quite unpredictable re- sults. Thus it is that oranges are sold from north- ern California before they are ready to pick in the southern part of the state. And again, the palm is a relatively hardy tree — I mean, of course, in comparison with tropical [Volume X — Chapter VII] LUTHER BURBANK plants in general. And whereas the date palm does not thoroughly perfect its fruit, for the most part, except in regions where the summer is very long, this tree may withstand extremes of tempera- ture that are widely removed from anything expe- rienced in the tropics, and other palms generally perfect their fruit wherever they can be grown. Indeed, so hardy are some of the palms that the question arises whether it may not be possible by selective breeding and adaptation to develop races of palms that will thrive even in the middle lati- tudes of the eastern United States, and far to the north of their present limits on the Pacific Coast. The fact that most of the palms now growing in California have been introduced within compara- tively recent times, and that they have gradually made their way northward, is suggestive of the possibility of much wider extension of their habitat. A difficulty in the attempt to carry out any project in selective breeding calculated to give the palm additional hardiness or any other quality is found primarily in the fact that this tree does not mature its fruit until from ten to twenty-five years of age. But in recent years an effort is being made by the Department of Agriculture and by several private individuals, to introduce races of date palms that will bear marketable fruit, and the [200] A Burbank Protege This palm, now 44 years old. was set out by Mr. Burbank when he first came to Santa Rosa. It is a thrifty specimen, and may be expected to outlive many human generations. LUTHER BURBANK study of the palm that has been undertaken in this connection will doubtless lead to important results. Even now it has been demonstrated that just as good dates can be grown here as in the Sahara. It appears that the palm, notwithstanding its relative fixity, is subject to considerable variation, and that this is particularly true of the date palm fruit, as might be expected considering that this tree has been under cultivation from pre-historic periods, and because it has been selected for the fruit alone. The most delicate and delicious date fruits are not the ones that can be secured for export, so that these varieties can never be seen on the American market until they are grown here. All the best date palms, unlike most other palms, are grown from suckers which come up from about the roots of the tree. To be sure, the Oriental peoples, for whom the date has supplied a most important food product from the earliest periods, have probably paid very little attention to selective breeding. Still the broad general fact that "like produces like" has been matter of common knowledge from remotest antiquity, and it can hardly be doubted that a cer- tain amount of more or less intelligent selection of the trees that bear the best fruit, with attempts to raise seedlings from these trees and thus secure [202] ON SOME ORNAMENTALS races of good fruit-bearers, has been practiced, generation after generation. Moreover a certain amount of cross-pollenizing between allied races of palms has doubtless taken place without the agency of man, and so it is all but certain that the different palms under cultiva- tion bear mixed racial strains, somewhat as do the different races of orchard fruits and cultivated plants of temperate climates. It is quite to be expected, then, that the palms grown from the seed should show a good deal of variation. That such is really the case is made obvious to anyone who attempts to raise them. The date palm, for example, may readily enough be grown from the seed, for the seeds germinate readily, though slowly. But the tests have shown that the progeny of a date palm bearing fruit of the best quality cannot be depended upon to transmit the characteristics of the parent with a high degree of certainty. So it is necessary to grow the young trees from suckers if the strain of the parent is to be perpetu- ated accurately. The experts of the Department of Pomology at Washington and several private individuals, have imported rooted suckers, obtained from female trees known to produce fruit of excellent quality, [203] A Familiar Ampelopsis There are several species of ampelopsis ****"*<«***; . Burbank has worked extensively. The spray here shown is thefamUiar Ampelopsis auinauefolia, common ^fnownas the Ur- ainia Creeper, and sometimes spoken of as the flve-leaveaivy. Mr Burbank has performed interesting hybridizing ex- periments with members of the family and has produced some rather important new varie- ties of crossbred ampelopsis. ON SOME ORNAMENTALS distributing them and planting them in various regions of the southwestern United States. The trees that grew from these suckers have proved to be pistillate, as expected, and produced fruit equal to that of northern Africa. Consider- able difficulty was experienced in securing suckers from the best trees, even private individuals not being allowed to own them in the original country. As to the date palm, the progress already made in the improvement of the fruit indicates beyond the shadow of a doubt that still further improvement will be made in many directions. Tt is probable that the colony of fruit-bearers thus introduced will spread indefinitely, until the date palm be- comes an important economic tree in warmer portions of America. It is even more important with the palm than with other fruit-bearing trees that propagation should be carried out in this way, because when the plants are grown from the seed only half of them will be bearers of pistillate flowers. The pollen-bearing trees will of course bear no fruit, and while there must be here and there one of these in the palm grove — one pollenate to about twenty-five pistillate trees — it would be an obvious waste of space to give over half the ground to sterile trees. Yet there is no way of determining whether an individual tree is a male or a female [205] LUTHER BURBANK until it comes to the age of blossoming; and the palm is a tree of slow growth that matures only after a good many years. But trees grown from suckers will be of the same sex as the parent trees; hence the double utility of propagating by this method. Palms for Ornament From the standpoint of the present chapter, however, the fruit-bearing qualities of the palm are not so much in question as its ornamental character. Considered merely as ornamental trees, there are members of the genus Phoenix, to which the date palm belongs, that are more attract- ive than this famous fruit bearer. And in general the character of the form and foliage of a date palm is carried with sufficient certainty from parent to oifspring by the seed to make it perfectly permissible to raise palms from the seed for orna- mental purposes. Even where the seeds are planted in rows, with the expectation of producing colonnades of palms, along road sides or for borders, the palms may be grown from the seed without danger that they will vary sufficiently to interfere with the symmetry of the row, provided the seed are gathered from the same tree, or at any rate have come from the same region. If, however, the seed be imported from different [206] The Bottle-Brush Bush This is a shrub from New South Walet :; a rather tender • plant, but thriving out doors at Santa Rosa. It belongs tome myrtle family. See the following picture in explanation of the pop ular name of this shrub. LUTHER BURBANK regions, there is probability of a good deal of variation even among trees of the same species. The more usual method, however, in California, is to germinate the seed in a hothouse, growing the young plants in pots at first, and then removing them to boxes that they may be more readily transplanted, as they make slender, wiry roots. They are as easily grown as kernels of corn, though requiring much longer periods of time. Occasion- ally, however, they are planted in nursery rows, and it is sometimes desirable to transplant them after they have obtained a growth of twenty or thirty feet in height, and a diameter of trunk of one or two feet. In such a case, it is necessary to cut around the roots of the tree some time before removal, making a ball of earth that is to be removed with the tree. This treatment induces the palm to throw out new roots, giving added firmness, and making provision for the rapid absorption of moisture and nourish- ment after transplantation. A box being constructed around the soil, the palm may be removed to any distance. Sometimes a single palm thus transported is of such size as to require an entire flat car. But unless the precaution is taken to cut back the roots and allow them to stand for some time before removal, as just suggested, there is danger that the [208] ON SOME ORNAMENTALS palm will die after transplantation, because the loss of its long roots makes quick adaptation to the new conditions impossible. The Phoenix canariensis is a thoroughly hardy palm in this climate, and the handsomest of the hardy members of the tribe. It is therefore the one most used for planting for ornament in California, though the Chamae- rops excelsior from Japan is as hardy and next most common. The Canary palm grows with great rapidity after the plant has the first five or six leaves, although like all other palms its early growth is slow. An ordinary specimen of this species, transplanted into good soil in this region when it has four or five leaves, will grow to a height of fifteen feet, with a corresponding spread of branches, and develop a trunk eighteen inches in diameter in six to ten years. No other palm with which I am acquainted will make more than about one-fourth this growth in the same time and under the same circumstances. There is considerable difference in appearance, however, and in rapidity of growth of different strains of palms of this species. Yet the seedlings are unusually true to type, so that long rows of the Canary palms may be grown from the seed with full assurance that they will not vary sufficiently to break up the general uniformity of the row. [209] Blossom of the Bottle-Brush A glance shows why this plant has received its popular name. The technical name of the shrub is Callistemon, from a Greek derivative, implying "the flower with beautiful stamens. There are several species of the genous, most of them hav- ing flowers with stamens of a beautiful scarlet color. The one here shown is a selected variety of Callistemon lanceolatus. ON SOME ORNAMENTALS Palms of the genus Chamaerops are also very hardy, perhaps even hardier than the Phoenix palms. I have never known one of them to be injured by frost anywhere in California, even when quite young. There are several species of this genus. I have grown them from the seed somewhat extensively, and have noted a wide variation among different species, some making large trees, while others are dwarfs, some of which, in this region, never attain a height of more than three or four feet. One exceedingly thorny species may be multiplied by division readily, as it throws up suckers abund- antly around the old plant, unlike most other palms. Some accidental hybrids have appeared among the species of Chamaerops. Variation and Development Notwithstanding the considerable variation among the different strains, there is almost no dis- coverable variation in seedlings of a species of this genus of palm when grown from seed of the same tree. The species most commonly grown in Cali- fornia is C. Excelsa. This is a species that in China and Japan is one of the most useful of trees, its foliage being used for thatch, the rigid leaf stalk for braces, and the woolly substance about its trunks for cordage and other purposes. Moreover this is the palm from which fans are [211] LUTHER BURBANK usually made, the undeveloped, immature leaves being used for this purpose. The palms of this genus usually bear the stamenate and pistillate flowers on different trees, but it is not unusual to find a few stamenate blos- soms on pistillate trees, or, contrariwise, a few pistillate blossoms on stamenate trees. This, however, is a matter of no great practical import- ance, since the trees are grown in this region only for ornament, and it is not necessary to raise them from the seed, as they put out suckers abundantly. On the other hand, if the attempt is to be made to hybridize the different species with the hope of developing hardier races, the matter of fertiliza- tion of the flowers becomes obviously important. It will be worth while, then, to select the trees with reference to those that tend to mature their fruit early. But the work of developing a race of hardy palms will necessarily be a slow one, requiring the co-operative labors of successive generations of plant experimenters. And whereas it is probable that in the course of a century or two hardy palms will be developed, so that the question of selection of ornamental palms will be of interest even to residents of the middle and perhaps even of the northern regions of the United States, at the mo- ment the matter can have practical interest only [212] ,, "J fft *L* ft 3. 5 ° 3 e S a -g-S ■ <* " Sr « •* 8 - >a ft. .. n 3 C S „ 2 a n -s^s a !a re a ^ © ~ •— § < 3 "1 o c S t •=:<: -.5 e © , .5; *• a 8CshK 3SS-53 cf-,5E-c3u CO -c E-. fc -2 - ~ 2 S 4 S * © Sec g- •«. a *-*; «"B a O «) » J; *; y 3 g as c S ■ 2*; 2 ;2 ft; c * s ON SOME ORNAMENTALS stem or twig, which will be grasped as the trap- like stigma closes, and held as a frog might hold a stick in its mouth. The same remarks apply also to the unrelated mulus, or monkey flower. Good work may be done by crossing the hardy bignonia with the tender ones, with excellent pros- pect of producing new varieties of value. Another ornamental vine that offers good op- portunities for the plant developer is the familiar and beautiful Wistaria. There is a fair degree of variation among the different species of wistaria, some bearing blue flowers and others white ones. The plants of this genus are not only valuable as climbers, covering walls and arbors with vines that bear beautiful flowers, but they can also be trained to form tree- like bushes that are most attractive additions to the lawn. The Chinese wistaria is ordinarily a long vine, but may be trained to a bush five feet across and thrive fully as well. Under this mode of culture, a certain amount of energy that would ordinarily go to the production of the vine itself is saved and utilized for flower production, so that wistaria bushes thus trained become astonishing bearers of blossoms, like gigantic bouquets. Nothing more is necessary in training the vine than to trim it to form a head, and then from time to time to cut out the straggling branches. . [229] LUTHER BURBANK The wisterias are difficult to hybridize, because their flowers are papillionaceous, like those of the peas and beans. But with a little care, hand-pol- lenation may be effected, and some very striking variations should be obtained in the second gener- ation from a cross, for example, between the American and Chinese wistarias. A complex hybrid between these species and the Japanese variety, Wistaria multiguga, which produces astonishingly long racemes of flowers, should give results of additional interest. My own experiments with the wistarias have consisted of the growing of a great number of seedlings, both of the Chinese and American species, selecting among these for plants varying in form, and bearing blossoms of different size and colors. The results of these experiments show that the wistaria is an adaptable flower, and one that is almost certain to repay more extensive breeding experiments, in particular those that introduce the element of hybridization. I will name only one other type of ornamental vines, this being the Lapageria, or Chilean Bell- Flower. As an excuse for selecting this one among many tropical and sub-tropical forms, I may say that when I first saw the Chilean bell-flower I thought it the most beautiful flower of any kind that I had [230] s s ~S3 | 35 E D ft 2 g ~> 3 '5 n n HI «. ^ ft a « H 5? « 2 2. » o c ~ ft ■a s f* 5> ■ 3 .£ o 3< £. s a. J? n o*«? o a* - a ~. a &<£ las a- "» 5 © S B S § a 5 £3 1 3 B g". §" 0-3 a a n » . A»*fc\- ~ re ' O" fe ^ «. ^S-^S «> iu S re :? ~ =3 2. s- ^ ** «■ £ SSrWftftreSfta-* S. ft re o- 3 ijnasi ' »- . $ - ff • «-a.a ^c* a S § a-^>5; .-. ~. re _ 2 O ~!^2-C:'*~,» S fits a c re a > ~~-=,e. Co LUTHER BURBANK at the head of the list, must be relied on in colder climates. It is not necessary to refer to the com- mon lawn grasses here in detail, their general character and qualities being familiar to everyone, and there having been no marked development in recent years in the way of improving them. It suffices to suggest that care should be taken in buying seed from reputable dealers that grass of good quality may be secured and the number of weeds minimized. Beyond that it is hardly to be expected that the interests of the amateur plant developer will extend. For the grasses do not offer opportunities for striking results in the way of improvement that make them appeal to the amateur. And, in any event, the blue-grass in its best varieties constitutes a lawn grass of really fine quality, and if properly cared for will produce a lawn of a very satisfactory character. Mixtures are never better, and seldom as good as the pure Kentucky blue-grass lawn. As to the matter of soil for the lawn, nothing specific need be said beyond the statement that the same sort of preparation is desirable that would be used in preparing soil for field or garden crops. Some details as to this will be given in the succeeding chapter. But I should like to offer a few practical hints as to such preparation of the lawn as will ensure a [244] ON LAWN BEAUTIFICATION proper regulation of the supply of air and water, upon which the condition of the lawn so largely depends. What is true about drainage and irriga- tion will have equal application to land that is to be used for raising flowers or vegetables or small fruits. Indeed, my suggestions are based very largely on my personal experience at Santa Rosa in preparing the ground for the experiment gar- dens on which plants of several thousand different species, and representing many families from all parts of the globe are grown. A Practical Drainage System Many hundreds of persons visiting my experi- ment grounds at Santa Rosa each season have mar- velled at the exceedingly varied and prolific crops raised — exclaiming, "What a delightful soil you have!" Their surprise grows when they are assured that this productive land was originally almost valueless for growing plants. It was made fruit- ful by artificial drainage and irrigation. The ap- plication of the simplest principles of regulation of water supply resulted in transforming a relatively sterile soil into one of the most fertile areas of the earth's surface. The method in which this was accomplished may be outlined as offering a model that may be followed to advantage in draining similar land anywhere. [245] LUTHER BURBANK Probably half the low-lying soils in the United States could be made more productive by drainage. Even if the soil of your lawns and gardens is fairly productive, you may advantageously consider the advisability of introducing such a system of drain- age as that which we have employed at Santa Rosa with such striking results. The soil consisted of what is called adobe, a black clay-like soil, said to be of volcanic origin, and this particular piece cracked so during the latter part of the dry season, that it was considered unsafe to pasture stock on it, as it endangered the legs of the animals, the cracks being often several inches in width and apparently bottomless. No crop had been grown here for years; and house lots a mile or more out sold for about the price I paid for the four acres. Of course there is nothing novel about the statement that the drainage of land is important. The matter has been more or less understood since the earliest periods. Yet a very large part of the land of the United States that is given over to lawns and gardens is left to depend entirely on natural drainage, and fails to produce anything like the crops that might be grown on it, if a more rational provision had been made for adjusting the water supply. In California the value of drainage has been [246] Bouquet of Campion Flowers This pleasing flower has been grown by Mr. Burbank and improved by careful selection. The plant is hardy and prolific, and there are numerous other species with some of which hybridiza- tion might doubtless be effected. LUTHER BURBANK shown in the results obtained even with wheat on fields drained and those not drained. Only one or two ditches across a field have made it possible to produce two or three times as large a crop as was grown in the same field before the ditches were made. In a certain oat field in Wisconsin, the yield per acre was doubled by drainage. The yield before drainage was only sixteen bushels, but after drain- age it increased to 32.3 bushels per acre. There are at least two bad effects to be expected from an oversupply of water. They are: (1) An oversupply makes certain areas so soft that they cannot be cultivated at all or at least not until late in the spring. (2) Air, which is essential to plant growth, cannot enter the soil supplied with a superabund- ance of water. Air is as necessary to the roots of plants as water and it is upon this principle that all systems of cultivation and drainage are based. The complicated chemical changes in the growth of the plant cannot take place unless there is sufficient of both air and water. Roots cannot exist where there is a superabundance of water in the soil. There are several systems of drainage which will not be discussed here. I -consider underdrain- [248] LUTHER BURBANK age with common drain tile the best system for ordinary conditions, and it is with this system that I have had most experience. The discussion is given mostly from the viewpoint of results on my own grounds. Small, well-burned drain tile was used on my Santa Rosa ground carefully laid with a slope of 1 foot to 40 feet and it has proven eminently satis- factory in every respect for twenty years. The soil is a heavy adobe and was almost worthless before it was drained. The good results of the drainage were scarcely apparent the first year, but the benefits were mul- tiplied each year until now the soil is easily culti- vated and bears enormous crops while before draining no crop could be raised. This system consists of one main line of 4-inch tile with laterals of two-inch tile every 40 feet. The laterals gather the surplus water quickly after a heavy rain and the main tile carries it to a small stream near by. The laterals do not need such a large capacity as most people think. It must be remembered that they work both day and night, and Sundays as well as week days and a very small tile will carry a great amount of water in the course of twenty-four hours. It is a good plan to have the tiles flushed now [249] ea. "9 X*: ~ J3 a «< 5£ *§5 Si!*53 - -2 is" a 8 ■§«^°& *>~-sa0 ~ C u © ON LAWN BEAUTIFICATION and then, and if they are not too large they will sometimes be flushed during heavy rains when they are filled to capacity. This flushing serves to keep them clean and the flushing produced natur- ally when small tiles are used is sufficient reason for recommending the smaller sizes rather than larger ones which are more expensive and gen- erally less efficient. The general impression is that cracks should be left, and sand put in the cracks. The real way is to surround the joints with clay; then they are permanent. The worst thing to do is to put sand or gravel or straw about the cracks. A tile four feet deep will drain twice as wide an area as a tile two feet deep. About four feet is the proper depth. The strength of the entire system depends upon the weakest section. Therefore it is necessary in laying the tile to examine carefully each piece, and to see that they are well burned, but not sufficiently to make them impervious. The system must be laid upon the proper grade, for if the line sags, sediment will collect and retard the flow of water. It is best to make a silt basin at some point where the branching tiles unite. This is formed by digging down a foot or two, and bricking or cementing up a barrel-like receptacle, the entrance pipe from the main system being a little lower than the exit pipe, so that the silt settles. [251] LUTHER BURBANK In the twenty years since the tile system was laid at Santa Rosa, the tile itself has never been exposed, or in any way touched or examined. It continues to perform its function perfectly. Drainage is really a science in itself, and there is not enough space here to give a full discussion of it. There are a number of good books upon the subject, however, and the names of these will be found in the chapter on reference literature. Before the system is installed, some complete treatise on drainage should be thoroughly studied. In some cases it is possible to secure the aid of a person who has had experience in laying drain tiles, and where this is possible it is the best plan. Supplying Water Irrigation is closely allied to drainage. The two systems are for a similar purpose — to regulate the amount of moisture in the soil for plant growth. Irrigation is needed in locations where there is not sufficient rainfall to insure the growth of cer- tain crops. In many places also where the rainfall is sufficient but not well distributed, irrigation will be profitable, especially in seasons of unusual drouth. For large tracts such as orchards and extensive seed and vegetable gardens, the common practice is to run water in large ditches with a system of smaller ditches throughout the field. [252] ON LAWN BEAUTIFICATION If such a system is properly constructed and cared for, little is wasted because it is placed very close to the point where it is needed. For small areas, sprinklers are generally used. The fault with most of the common sprinklers used to irrigate small areas, such as lawns and small gardens is that they do not distribute the water evenly. Most of them cover a circular space and there is always some part of the soil which has too much water or too little. One of the most im- portant points in irrigation is to have the water distributed evenly. Some flat or fish-tail sprinklers distribute water quite evenly, but the newer system of overhead irrigation known as the Skinner system is, in my judgment, by far the best for small areas, and possibly for all areas of any size. This consists of a number of one-inch galvan- ized pipes with nipples placed along the sides about 12 to 20 inches apart. These pipes with the nipples inserted are mounted upon supports about 6 feet above the ground. The pipes are connected with the water supply and the water turned on when needed. Depending upon the pressure, this system will distribute water evenly for a space of from 25 to 50 feet on either side of the pipe. The pipe may be located between two beds so that it may be turned [253] A South American Flower This strange flower with its unusual markings, was grown from seed sent to Mr. Burbank by a South American missionary. It is one of many such which have encouraged Mr. Bur- bank to further experiments toward improvement. ON LAWN BEAUTIFICATION on its support and distribute the water on either side. When advantage can be taken of the wind, the water will be thrown almost twice as far as when there is no wind. This system has been somewhat modified to adapt it to small areas where irrigation is not needed often. Instead of mounting the pipes upon permanent stakes, they are carried from one place to another as irrigation is needed and placed upon temporary supports or movable stands. For greater convenience in handling the pipes, the temporary supports are only about 4 feet high. On the top of these is nailed a curved piece of sheet iron in which the pipe rests. The movable stands are made of galvanized pipe in tripod form and can be made by any plumber. The sprinkler pipe is attached to the water supply by a rubber hose and the system operates in the same way as when in a permanent location. This system is patented but it is not expensive to install. The pipes can be purchased at any hardware store but the nipples and the tool for drilling the holes in the pipe for the nipples are patented and must be purchased separately. Many of the seed houses, that handle tools in addition to seeds, sell this irrigating system. When this system is to be used on a lawn the supports can be made more or less ornamental. [255] LUTHER BURBANK The cost of irrigating lawns by this method is far less than by the use of circular sprinklers, for both time and water are saved and the lawn is supplied with a more even distribution of moisture. There is another plan of irrigation which is known as the underground pipe or tile system. This is not often used because the first cost is too great. In some cases, however, it has proven to be satisfactory. The part of any sprinkler system that deteri- orates most rapidly is the rubber hose. When it can be replaced by iron pipe it should always be done to save expense. Where hose is used it is usually necessary to purchase a new supply each season. Its first cost is two or three times more than that of a galvan- ized iron pipe and the pipe usually lasts from ten to fifteen years. There are several other systems of irrigation of lesser importance, but it is not necessary to describe them here. The Menace of Weeds However well the soil may be prepared for garden or lawn, and whatever the attention given, the cultivated plants of every description are per- petually menaced by the rivalry of weeds. A weed may be said to be a plant out of its proper place so far as the economy of man is concerned. [256] ON LAWN BEAUTIFICATION This does not mean, however, that it is out of its proper place in the economy of Nature. Nature has a use for weeds and in fact they have done much good for man. When crops were first cultivated, farmers stirred the soil in order to destroy the weeds. They did not then fully realize that stirring the soil aided the growth of the crops. They did dis- cover, however, that when the weeds were de- stroyed much better crops were produced, and thus the weeds forced farmers to stir the soil and allow the air, so necessary to the plants, to circu- late among the roots. Now that the farmers have learned the real reason for cultivation at the proper times, whether there are weeds present or not, the destruction of weeds assumes a different aspect. Weeds are a detriment in many cases from the fact that when proper precautions are not used they take possession of areas of land so that it is impossible to grow useful crops. There are two general classes of weeds, annuals and perennials. Annual weeds reproduce themselves by seeds which mature each season, usually in great abun- dance. Perennials, in cold climates, although most of them produce seeds, also perpetuate themselves by storing food and living matter under the ground [257] LUTHER BURBANK where the life of the plant is protected until spring. Many perennials have underground stems which are sent out in all directions. From each node a new plant may grow under the proper con- ditions. It is obvious that such weeds are most difficult to destroy because, although they may be pre- vented from bearing seeds, they distribute them- selves over large areas. The handling of annual weeds is summed up briefly in one sentence: Prevent the production and the introduction of seeds. But with perennials not only must the introduc- tion and production of seeds be prevented, but the entire plant must be uprooted and destroyed. When perennial weeds have taken possession of an area of land, they may generally be brought under control by thorough cultivation during one or two seasons. This often means that one or more crops must be sacrificed. Every weed on the entire area must be destroyed as soon as — and with some kinds before — it appears above the surface. The vitality and food provided by perennials in most cases does not keep the plant alive more than one season. The plant depends upon its store of food being replenished by another growth each season. If the leaves cannot develop above the ground, so that raw food collected by the roots [258] ON LAWN BEAUTIFICATION can be digested and stored again underground, the plant cannot grow the following season. Thus it is that by cutting off the plants continually for an entire season as soon as they appear above ground they will die out and not ap- pear again on that area unless, of course, the seeds are again introduced. Most weeds are provided with greater facilities for reproduction and distribution than cultivated plants. Most weeds also have some special means for distributing their seeds over large areas. Many of them, such as cockleburs (Xanthium) , sandburs (Cenchrus), burdock (Arctium) and stick-tights (Bidens), have burrs surrounding each seed which are made up usually of many hooks or spines. These seeds attach themselves to the clothing of persons and to the various domestic animals, and are thus transferred from one locality to another. Many of the weed seeds such as the thistles, wild lettuce, dandelions, etc., are provided with a feathery portion which assists their carriage by the wind. Other seeds are borne in pods which, when dry, open with a suddenness which throws the seeds great distances. Some seeds are borne in fruits which are relished by birds and animals. The seeds in this [259] South American Grass This is an unnamed grass from South America, which has interest because of the curious panicles (suggest- ing plumes of a bird of paradise), in which its seeds are grown. This is one of a great number of grasses with which Mr. Burbank has experimented. ON LAWN BEAUTIFICATION case are usually small and are provided with a hard coating so that they are not destroyed by di- gestion in the bird's or animal's stomach, but are carried great distances and on reaching the ground are usually in best condition to germinate. Most weed seeds have the ability to retain their vitality for a long time. Farmers who have plowed fields deeply have sometimes noticed that a certain weed which was present the year before plowing disappeared entirely for two or three years only to reappear again later. This was due to the fact that the seeds were placed by the deep plowing several inches below the surface, and when the soil was plowed deep again they were brought nearer the surface. In some cases, seeds have been known to retain their vitality for twenty years or more. Although weed seeds are provided with many more contrivances to secure a wide distribution than those here mentioned, this is not the only pro- vision for their perpetuation. Living as they do among many discouragements and difficulties it has been necessary for them to provide protection for the plants themselves against unfavorable weather conditions and against animals. Some weeds have the ability to withstand long and severe drouths while others are able to grow where there is a superabundance of moisture. Some are able to withstand extremely low temperatures. [261] LUTHER BURBANK Protection against destruction by animals is afforded by spines, thorns, bitter juices, and poisons. Understanding these provisions of Nature for the production and perpetuation of weeds it is quite apparent that prompt and efficient methods must be used by farmers and gardners in destroy- ing them on first appearance. A few mustard, thistle, or dandelion plants which seem harmless because there are so few, may spread to such an extent that in a few years it will cost thousands of dollars to rid an infested area from the pest which, if destroyed while still few in numbers, would have cost only a few dollars or dimes. Weeds are much like a leak in a boiler or a fire let loose. They are easily attended to at first, but lead to destruction if proper attention is not given in the beginning. Never is the old saying "A stitch in time saves nine" better exemplified than in the case of weeds. As has already been intimated, many fields are infested with weeds through the introduction of the seeds in the seeding of the crops to be grown. Weeds that thrive particularly well with certain crops sometimes produce seeds so like the seeds of the crop in size and appearance that it is often practically impossible to separate them. [262] ON LAWN BEAUTIFIGATION In many sections a weed known as corn cockle (Agrostemma) is a pest in wheat fields. So nearly do the seeds of the corn cockle resemble the kernels of wheat in weight and size that for a long time it was almost impossible to separate the cockle seeds from the wheat. This, of course, caused millers a great deal of trouble for the corn cockle seeds have a black shell about them which discolors the Hour. Finally a special machine was constructed for the removal of cockle seeds. The perennial morning-glory, commonly called the devil's shoe string, has often palmed seeds off for wheat among screenings fed to poultry, being about the same size and has established itself on much of the best soils in California. The darnel (Lolium) commonly called cheat, infests grain fields in some sections and so well have the seeds masqueraded that many farmers thinking their seed was thoroughly clean, later found this weed and have said that the seeds changed into wheat, barley, oats, or whatever the grain happened to be. This mimicry, of course, is developed by evolution. That is, those seeds which are most nearly like the seeds with which they are mixed are overlooked in cleaning and remain to per- petuate the race. After many generations of this sort of natural selection, the seeds constantly [263] LUTHER BURBANK approach the grain seed in form, size, weight and color. The seeds do not change their botanical characters as farmers suppose, but having a hard coat, may lie in the ground until a wet season when the grain is destroyed and the darnel takes its place. Many states have long maintained official seed inspection for purity. Now there is a United States law of similar nature. These laws have been so well enforced that there is not so much danger now of infesting land with weed seeds as was the case a few years ago. Farmers who make a practice of buying grain for seed from their neighbors or other persons who have not had their seeds examined by inspectors are likely to have their fields infested with noxious weeds. From a small sample, the quantity and kinds of weed seeds may be determined. This is especially true of alfalfa, clover, and lawn grass seeds. If the sample contains weed seeds, it had better be rejected for there are always weeds enough to contend with without sowing more. Grains, clovers, and grass seeds are far more apt to have foreign seeds mixed with them than any other class of seeds as they are usually harvested by the wholesale, weeds and all, and it [264] South American Thistle Mr. Burbank takes a great interest in the thistles. He believes that they are capable of being developed into useful commercial plants. Here is a South American species with which he is experimenting, first endeavoring to remove its thorns. LUTHER BURBANK is only by careful screening that the other seeds can be removed. With seeds of hoed crops, such a condition does not exist. It is impossible, of course, to give here a complete description of all the different kinds of weed seeds, but pictures are given in the natural color of some of the most common ones. By com- paring the seeds with these pictures it will usually be possible to determine the kind of seeds that are found in your locality. Of course, one must always expect to find a few foreign seeds in a sample of grain, but remem- ber that the weed seeds cost the same price per bushel as the oats. That is, if the price is $2.00 a bushel for oats, you pay $2.00 a bushel for the weed seeds which are not only worthless but a detriment to the crop. In orchards, especially in California, the two worst weeds are wild morning-glory and a new species of perennial amaranthus. Both of these produce many long and persist- ently sprouting roots. The morning-glory sends its roots to great depths and has taken possession of many acres of the best land. This, of course, greatly reduces the production of crops and the value of the land. The overrunning of a field is due to the fact that the owner of the land was careless in not [266] ON LAWN BEAUTIFICATION destroying the morning-glories when they first appeared. This weed spreads in all directions like a fire and its spreading is increased by ordin- ary cultivation, as small portions of the roots are carried by the cultivator to other locations where they soon grow into new plants. It is extremely difficult to exterminate the perennial morning-glory in orchards and vine- yards because the ordinary cultivating machinery does not run close enough to the rows. The only way to exterminate this weed is to spend all the time and labor necessary for one whole season in cutting off the plants before they appear above the surface. This may be done with a cultivator made with sharp knives that run under the surface. It will be necessary to go over the ground regularly at least once a week. If this pest is allowed to produce any foliage it gives the plant a new start. The common amaranthus produces an enorm- ous amount of small black seeds. It is an annual and is often called careless weed, because it is seldom found in abundance except on land that has been carelessly cultivated. Thousands of seeds are produced by a single plant and they come up during summer and thrive especially well on rich fertilized soils. The common amaranthus, however, is almost harmless when compared to the new perennial [267] LUTHER BURBANK species which has lately been seen in many public grounds, and is rapidly spreading to farms and gardens. This new weed, unlike the annual, sends down long slender roots deeply into the soil and if cut off, no matter how deeply, will immediately sprout with redoubled vigor. But this is not the worst. Like the annual, its sole object seems to be to produce enormous quantities of seeds. This new pest trails instead of growing upright and begins to produce seed almost as soon as the plants appear above ground. This seed production is continued as long as the plant lives. The only method of destroying this is to cut off the first plants which appear, and apply a small quantity of salt or sulphate of iron on the cut portion of the root, at the same time burning every portion of the plant removed. Mustard, wild radish, and wild lettuce, though annuals, are often difficult to exterminate as they are abundant seed producers. The best method of exterminating these is to destroy each plant before they have time to ripen seed. Usually it is possible partially to rid the land of them by plowing it thoroughly early in the spring and growing some cultivated crop. Sheep sorrel or red weed, sometimes called "shamrock," is another most persistent weed, very [268] ON LAWN BEAUTIFICATION hard to exterminate if once established, especially in lawns and moist shady places. It is a persistent producer of runners, as well as seeds that are projected a great distance when ripe. It seeds abundantly when the plants are quite young. When the seeds are ripe they are pro- jected with great force in all directions. This is best exterminated by unremitting destruction with the hoe before the plants produce seeds. There are numerous other smaller and more insignificant weeds such as shepherd's purse, sev- eral senecias, chickweed, and others which are not as persistent as those already discussed, but which should be kept well under control by thorough cultivation if good crops are to be produced. It should be borne in mind that weeds are enormously prolific, and that their seeds go every- where. So it does not suffice to keep your garden weeded and your lawn well mown. It is necessary also to pay heed to the weeds along neighboring roads for their seeds will be no respecters of your boundary lines. You will be taking steps toward enhancing the beauty of your lawn next season, and will be lessening your work in the flower bed and vege- table garden if you use scythe and hoe freely on the weeds growing along the roadside everywhere in the neighborhood of your garden. [269] The Siberian Lily This interesting Asiatic plant is under observation in Mr. Burbank's garden, and has been improved by selective breed- ing as to the form and size of its spikes of flowers. It is an attractive novelty on the lawn. ON LAWN BEAUTIFICATION No effort that you could bestow would have a larger influence toward the beautification of your next season's lawn, and the lightening of your labors in next season's garden than that devoted to the destruction of this season's crop of weeds, wherever found. Flowers; and the Disposition of Trees Probably color is the most attractive thing about flowers. Usually solid colors are more attractive but harmonious combinations are almost as valuable. A graceful form probably comes next in attractiveness. Size and abundance of bloom next. Size does not always happen to be an advantage. Some flowers, as the heaths, are attractive because of the smallness of the blossoms. In this case the small size really adds gracefulness to the plant. Where the blossoms are small more are needed to make a good effect, so improvements on flowers with small blossoms should be made along this line where needed. Everyone must be his own judge of harmony in the colors of plants. Most fairly well educated persons have a sense of harmony to direct them to the combination of colors to work for. White is harmonious with all colors. A deep red is not harmonious with blue, except sometimes [271] LUTHER BURBANK with a pale blue. The sense of distinguishing har- monious combinations of colors has been more developed since aniline dyes were introduced. This is principally because with the aniline dyes almost any shade of color can be made. Before their introduction the unusual shades were not often seen. All the prismatic colors are beautiful and attractive in their proper place. The delicate shades of each of these colors are even more pleasing to the average educated mind. Red is the most insistent color. Yellow and orange are next. White is insistent. Black is insistent. In selecting flowers, I aim to pick those that are striking, harmonious, pleasing, and new in respect to color. In order to be able to select flowers for color one must be thoroughly familiar with all of the colors in each variety now in existence. Now that there are more people working for new varieties of plants it often happens that two or more persons will develop new varieties almost exactly alike at the same time. For this reason, it is usually more advisable to work with plants that are not so common. For instance, get seeds and slips from foreign countries, or take wild flowers and domesticate them. Each new flower should be developed for some definite purpose. Red is an appetizer even to the [272] Japanese Magnolia The magnolias are well known shrubs or trees of great ornamental value, owing to their very large and conspicuous flowers. There are a good many species, some of which are very hardy. The specimen here shown is a Japanese variety that Mr. Burbank has under observation. LUTHER BURBANK birds. They will always eat the red fruit before that of any other color. Red flowers are good for the dining-room, and orange or yellow will serve the same purpose almost as well. Delicate shades are needed for the parlor, drawing-room, sleeping rooms, and libraries. A pale blue is very good, and pinks and combinations of pink and white are especially pleasing. It is also desirable to have a bright color occasionally in these rooms where more quiet flowers are kept. This gives a dash and spirit that is needed. Practically all colors blend well with gray or brown as a background. Flowers banked around the foundation of a house represent an unconscious exhibition of advanced civilization. Vines give a peculiar grace to architecture and subdue unattractive colors. Green vines blend with any color. Flowers harmonize with surroundings and subdue undesirable colors or forms. Borders of flowers break the hard angles between a building and the ground. Perpetual bloomers and peren- nials are especially good near buildings. The tall ones should be placed close to the buildings and the small ones in front. The small flowers are better for the beds on the lawn or near the street. It is not well to put taller plants in bunches in [274] ON LAWN BEAUTIFICATION front of the home. A single tall plant here and there sometimes lends an artistic effect. Usually when tall plants are placed near the road, it is best to have those with thin foliage. Colors for yard planting should, of course, be those that attract the inhabitants. It is never, however, well to have a predominance of red. Flowers about the house serve to keep those living there in good spirits. They add a cheeriness that tends to keep people happy. White is always a good color. Blue is appropriate but must be accompanied by red or yellow, otherwise it gives a cold effect. Purples and deep crimsons do not always blend as well as other colors. Hedges and Trees and Shrubs The larger trees should be in the rear of the house. Fruit trees should be back of the house or to one side. The trees that shed their leaves should be on the south and east sides of the build- ings. This leaves the evergreens to protect during the winter. Trees with plenty of foliage should be planted on the southwest to protect the house from the hot sun in the summer. On large estates oaks and elms and the larger trees may well be planted even in front of the home. Evergreens, especially tall ones, should usually be set out rather sparingly. Do not put them too close to the house, as they [275] Chilean Wild Flower Mr. Burbank has received hundreds of wild flowers from Chile, the major part of which are unnamed and unclassified. Here is one that shows interesting peculiarities of petal that distin- guish it in almost any company and give it the interest of novelty. Also it is by no means lacking in beauty, as a glance at the picture shows. ON LAWN BEAUTIFIGATION keep out the sunlight and make the house dark. A number of evergreen shrubs are desirable to set off the place. Palms are good in a warm climate. Palms must not be crowded for they will suffer from lack of light and air, and will get out of shape. Usually the best way is to plant an abundance of palms, and later thin out those that are not doing so well. Sometimes it takes a great deal of courage to cut out part of the trees, especially if some of them have become favorites, but it will be to the detri- ment of them as well as other trees if the thinning is not done at the proper time. Evergreen trees and evergreen shrubs should be allowed to grow close to the ground. It may be of interest to add the names of a few of the more desirable ornamental trees and shrubs : Trees for Street and Ornament: Arbor Vitae, Big Tree, Lawson's Cypress, California White Fir, Silver Cork Fir, Maidenhair Tree, Silver Pine, Douglas Spruce, Tideland Spruce, White Spruce, White Ash, Basswood, Birches, Kentucky Coffee Tree, White Elm, American Holly, Magnolias, Oaks, Maples, Walnuts. Shrubs for Ornamental Planting and Lawn Decoration: Black Alder, Andromeda, Japanese Barberry, Button Ball, Spanish Bayonet, Choke- [277] LUTHER BURBANK berry, Flowering Dogwood, Inkberry, Jersey Tea, Laurels, French Mulberry, Pearl Bush, Wild Roses, Strawberry Bush, Sumach, Sweet Pepper Bush, Sweet Shrub, Wax Myrtle, White Fringe, Wistaria. Shrubs for Windbreaks, Hedges, Berries: Black Alder, Arrow Wood, Mountain Ash, Com- mon Barberry, Chokeberry, Coral Berry, Flower- ing Dogwood, Sweet Elder, Wild Grapevines, American Hazelnut, Huckleberry, French Mul- berry, Russian Olive, Osage Orange, Wild Yellow Plum, Sassafras, Sweet Shrub, Waxberry, White Fringe, Witch Hazel. — A very large part of the lawns of the United States is left to depend entirely on nat- ural drainage and fails to pro- duce what might be expected of it if provision had been made for adjusting the water supply. +&?£**■ Field and Flower Garden Some Practical Hints for Their Betterment ANY have thought that decreased yields are always due to the exhaustion of certain chemicals from the soil. This is not always the case. In fact, it is seldom that de- creased yields are due to the lack of plant food. Plant origination, the highest type of work with plants, has shown the underlying principles of soils and their use. The results of fifty years' work in getting big results from the soil are here summed up in such a way as to show the underlying principles of crop production. These principles are applicable on every farm, and may be applied in increasing the yield of any crop. Years ago farming and gardening were "hit or miss" performances. Farmers tried methods be- cause some one else had used them, and but few of them knew the reasons for any of the operations. [Volume X — Chapter IX] LUTHER BURBANK In order to understand how to select soils and how to secure the best results from them, one must know the underlying principles of productive ability of soils and the methods used by plants to secure food from them. Farming is now considered a manufacturing process. As a matter of fact, a farmer uses more kinds of raw materials and produces more kinds of finished products than any other manufacturer. It is just as necessary that he select his raw materials with extreme care as it is that the manu- facturer of machinery select the most durable kinds of wood and the strongest kinds of metal. Farmers have sometimes been criticised for not using more fertilizers but this is not always a just criticism. Fertilizers are valuable in some cases, but often a better physical condition of the soil would make it possible for the plants to secure enough food materials to increase the yield materially without adding fertilizers. Profit in crops depends upon the location of the crops grown, the use to which the crops are put, and the cost of fertilizing when fertilizing is necessary. There are other things which affect the profits, but these are the underlying factors. No definite rules can be given about handling the soil, for each one must work out his own practice according to his own conditions. [280] "2" W i ••San ! O S O 3 R J O 3 a a g O.o« w » •"■• Q * ~t •■- <-, a. 2. a " o-fre 2. «s a 5 a eg 2 a.55 Ga • o«, •*&•& i ° a * 2 H 2 a-a 2 "a til gaff a « i <5 ~ § re am ~. »- rs ■6 a a a o-fv • c» 5 5 3 » a? si C/0 o rs o © 3 LUTHER BURBANK The value of soil depends upon its texture, the elements it contains, the exposure, location, nat- ural drainage, the availability of the elements required, etc. A well-drained alluvial soil of fine texture is the most productive with the average crop. Furthermore, it is usually most durable in its pro- ductiveness. That is, its valuable qualities con- tinue to manifest themselves year after year. Other things being equal, a field located in a comparatively level valley or plain is more val- uable than one on the side of a hill. Often the soil on the side of the hill is rather thin and there is always the danger of washing. Rains come and carry the most valuable part of the field into the valley below. Of course, hillside fields are valuable for some crops. In fact, in some cases, where the soil is rich, even better results are obtained on the hills than in the valleys. This is especially true in California and semi-arid sections. North and east slopes are usually best for late crops, but the south and west slopes are always better for early crops. A slope toward the sun even of only one or two inches to the rod makes a difference in earliness of a week or more. This has been proven by many experiments. The northern and eastern slopes hold the [282] ON FIELD AND FLOWER GARDEN moisture longer but do not warm up so quickly. For this reason they are able to withstand drouth better, but never yield as early crops as the southern or western slopes. A clay sub-soil a foot or more below the surface with a sandy surface layer is the ideal soil for fruit trees. In fact, such a soil is good for most any crop. If the sub-soil slopes sufficiently to drain off surplus water, such a soil will always produce good crops. Chemistry and Physics of the Soil Plants secure their food from the soil through minute hair-like appendages on the roots, known as root hairs. The roots thus serve only as canals. The root hairs collect the food. Because of the extremely small size of these root hairs it is plainly seen that any food used by the plant must be thoroughly dissolved before being taken up. These root hairs are deciduous like the leaves, and only active to any extent where the leaves are in existence and active. All food taken up by the roots is secured in solution and this makes it necessary to keep the soil properly supplied with moisture. The presence of the proper chemical elements and moisture, however, is not the only thing that is needed for the root hairs to do their work well. Air must be present in the soil or it will be impos- [283] e «g i a, 5 s 5 5 a 5. fe 5 c a Si* a © «' ©><■> *, ■c •s *> t. 5 -^ "- c .SJS 2*: © 5 ©>*; ^ ©t! 1 e.^5 a 5 a . * "" K * — -» a a a ft" 3 5 b 5? =:?ea ' o B s ~ » 3 3 2 •ago ft** ft'l Q S ft Pq ; S 2 5 ;• K ft 'S'O 2 — *- M © «■ 1 "I *^> — . ° "* It's.?* s r* 7 i i o a TO * 2." a ;L 3 Sr <"♦• $ *a,2 5' ® „. o aa~,3 a S- LUTHER BURBANK And the third is by applying fertilizers which supply the plant foods needed, in an available form. It does not always follow that when the yield of a certain piece of land is small, that land needs fertilizers. It is very often the case that the poor yield is due to poor seed or shallow culture, or other cause. If great care is taken in selecting seed from the highest yielding fields year after year, one will then know that when the small yield comes it is due to something else. I do not mean to say that it is not necessary to fertilize, but I do mean to say that very often expensive fertilizers are added when a thorough stirring of the soil, drainage, or irrigation would accomplish the same result. Soil that is producing fruit crops needs less fertilizing than that producing grain crops. The fruits contain such a large percentage of water that the essential elements of fertility are exhausted from the soil very slowly. On the other hand, the grain contains a large percentage of the essential elements of soil fer- tility and it is necessary to add fertilizers to grain fields much more often than to orchards. Now that the fertilizer manufacturers are under government supervision it is safe to use any good standard fertilizer on the market. Many ex- [288] ON FIELD AND FLOWER GARDEN periments have been conducted to determine the right element in which the soil is lacking and supply that alone. The analysis of soils has often proven of value, especially in scientific researches, but it is not practical for the average farmer to have a chem- ical analysis made of his soil to determine what kind of fertilizer should be used. In practically every case good barnyard manure gives excellent results. In the same way, a fertilizer purchased on the market usually gives the results desired. Because of the complexity of the soil and the complexity of the requirements of the plants so far as different elements are con- cerned, it is plain to see that it seldom or never happens that any one element is wholly elimi- nated from the soil at a time. Sometimes an element which appears to be exhausted from the soil is merely in an unavail- able form. The addition of other elements in such a case, although they do not seem to be needed, may produce the required results because they assist the unavailable elements in changing to an available form. Nitrogen usually has the most immediate and pronounced effect upon crops when it is applied in fertilizers. Nitrogenous fertilizers always pro- duce quicker results, and when it is desired to get [289] •-go s: «- >« 2 S a<*" 0 3 5! © ~ W 3 | c 1 ^ -| « - ° -~ ^ 3 fc ■3 a a jar *&!*** e C ON FIELD AND FLOWER GARDEN early crops, these are the ones to use, especially in the early part of the season. Nitrogen is quite often in the form of ammonia in the fertilizer. Ammonia is very volatile and escapes into the air rapidly if not properly in- corporated. A commercial product that has a strong odor indicates that the ammonia is escap- ing into the air. Use a fertilizer when it is absolutely necessary, but make sure first that some cheaper process, such as cultivation, irrigation, drainage, or rota- tion of crops, will not accomplish the same result. The physical condition of the soil in practically every case is more important than the chemical condition, that is, it has a more direct effect upon the crops. Increasing Crops by Rotation Many flower lovers have been dismayed at having a favorite collection of lilies almost entirely destroyed by insects. Such a disappointment can be generally prevented by moving the lily bulbs. Great fields of grain, and large orchards of valuable fruit trees have produced smaller yields year after year until it was finally impossible to grow a profitable crop at all. The remedy is rotation. Each grower must be his own doctor, however. There is no short cut to profitable crop yields. [291] LUTHER BURBANK They are obtained by the man who understands the bad effects of growing the same crop on one field year after year, and who knows that these effects can be avoided by making a change in crops. Every horticulturist and every agriculturist should study what follows carefully. It tells why failures come, and why rotation forestalls such failures. There are at least four important reasons why rotation of crops is necessary. In the first place, insects which often gather in great numbers about certain plants are destroyed, or at least their number is reduced when other crops are grown on the land. This is because certain insects are adapted to depend upon certain plants for their nourishment. Lilies and amaryllis are often almost completely destroyed by such insects as mites, small centipedes, wire worms, eel- worms, etc. Absolutely new, uncultivated soils seldom are troubled. It is mostly in gardens where plants from various quarters are grown that difficulty occurs. These pests gather around the lower part of the bulb and if the bulbs are left in the same place several years the insects often destroy them com- pletely. [292] Blossom of Night Blooming Cereus The improved plant on which this beautiful flower grew is shown in the frontispiece of the present volume. Unfortun- ately the night blooming cereus is too tender to be grown except as a hot house plant in the colder climates of the eastern states; but it thrives in California, and deserves greater popularity than it has attained. LUTHER BURBANK Although this is not generally known it is the common cause for the destruction of lilies. Many have had beautiful lily beds exterminated and have been unable to determine the reason. Some- times by transferring the bulbs to another location, if thoroughly disinfected before replanting, they can be saved. If gladiolus bulbs, for instance, are planted in the same place year after year, they do not thrive. Usually there are fewer and fewer bulbs as the seasons progress, rather than more, and those that are produced are much smaller than the bulbs originally planted. The plants are also less vigorous. The third year the crop is almost a complete failure. It is necessary to practice rotation of crops with gladiolus. The same thing is more or less true with most other bulbs, as most of them have a bitter poison or protective principle that repels these insects. Some of them, of course, are not quite so suscep- tible to the ill effects as others. Various bacterial and fungous diseases also attack plants that are grown in one place year after year. These organisms, although they may not be entirely destructive the first year or two, grad- ually multiply and become a greater pest from year to year. [294] i ■■■ A Beautiful Flowering Cactus This is the cactus known as Opuntia basilaris, a low spreading form that makes a very striking contrast with the giant spineless opuntias in Mr. Burbank's garden. The present spe- cies is too small to be of any value as a forage plant, but its flowers give it high rank as a border plant for the garden. LUTHER BURBANK When trouble arises from this source th6 remedy is to rotate the crops or, in other words, move the crop infested to another location. Fungous diseases are especially destructive in potato fields. The potato scale, blight, and wart are well-known diseases which can often be wholly or partially controlled by the proper rotation and the planting of uninfected seed. The third cause for failures is the unfavorable condition of the soil produced by the toxic sub- stances thrown off from the growing plants. Plants, like animals, give off waste matter which is not only useless but poisonous to the plant itself, and often to other plants of similar nature. These toxic substances are often less poisonous, and in some cases are beneficial, to other crops. It is obvious that when waste products from a certain crop have accumulated in the soil for a number of years, that soil is not as well suited to the crop as formerly. A change of crops prac- tically always results in a more profitable yield because the waste products of the first crop are often not injurious to the second one. The fourth cause, which is far less common than the others, is exhaustion from the soil of certain elements necessary to plant growth. It is very seldom indeed that any one of the elements necessary to plant growth is wholly [296] i -. Sr S 6-a'S.B; " o ft ST "" e B 5 w a. i a m 2 re e *». re X re *§« ft • 2,25 LIST OF ILLUSTRATIONS (Continued) Thistle Page South American Thistle 265 Tigridia The Interesting Tigridia 79 Hybrid Tigridia 82 Another Hyb-id Tigridia 85 Variant Hybrids 87 Seedling Tigridias 89 Another Bunch of Seedlings 92 Bulbs of the Tigridia 94 A Blue Tigridia 97 Tigridia Seeds at Wholesale 100 A Nameless Missionary Flower 103 Verbenas Burbank Hybrid Verbenas 106 More Burbank Hybrid Verbenas 109 Burbank Fragrant Verbenas 112 A Bed of Burbank Verbenas 115 Vetch An Improved Crown Vetch 284 Virginia Creeper A Familiar Ampelopsis 204 Wild Flower Chilean Wild Flower 276 N. C. State Co\U