Popular Science 121(6): 44-45, 106 (Dec 1932)
New Plant Wizard Rivals the Great Burbank
Clarence Ebey

PLANTS that grow nowhere else on earth bloom in the gardens of William H. Henderson, near Fresno, Calif. With 150 new flowers, fruits, and vegetables to his credit, this young experimenter, less than thirty years old, is carrying on the work of the world famous plant wizard, Luther Burbank.

Among his creations are a species of Golden Bantam sweetcorn with twice as many kernel rows on every cob; a seedless Muscat grape that ripens and can be placed on the market months before other known varieties; roses that are velvet red and edged with black; iris that are tinted like orchids.

By crossing sugar beets with Swiss chard, he has produced a giant red-stalked chard, three or four plants of which provide the average family with greens for many months; with the aid of night-flying moths as big as humming birds, he has developed a new species of gladiolus, the flowers of which are no longer scentless but possess a beautiful perfume.

In 1922, Henderson graduated from the Fresno High School. He had always been passionately fund of working with plants, so he wrote to Luther Burbank asking for employment in his Santa Rosa experimental gardens. Out of 1,500 applicants for such work, he was the one selected. His first job was pulling weeds at $15 a week. For four years, he remained with Burbank, learning of the mysteries of plant life from the master horticulturist. During the last two years of Burbank's life, he was his trusted assistant. In 1926, when Burbank died, Henderson returned to his step-father's ranch, near Fresno, and began experiments of his own.

One of his first accomplishments was the development of an improved zinnia. These common flowers, so ordinary-looking they are often nicknamed "the kitchen garden flower," are usually dull in color and ungainly in appearance. By crossbreeding and selection, Henderson increased the brilliance and clearness of the comes and lowered and broadened the plants, making possible bedding that will present a mass of rainbow hues. The most striking of his new zinnias is tri-colored. It has an outer circle of lavender, an inner circle of cream, and a center of pink.

A giant, ever-blooming amaryllis, a lily-like flower that originated in South Africa, is one of his recent achievements. Common varieties were crossed with evergreen types to combine the ever-blooming feature with a new range of colors and petals of unusual star. Many of these massive blooms have n diameter of fourteen inches—more than two inches greater than the length of this page!

ANOTHER giant flower that grew for the first time in Henderson's garden is an improved hibiscus, or mallow, of unusual hardiness and arresting colors. New varieties of Shasta daisies have resulted from other experiments. Among them are some with strange, quilted petals and many with unusually large blooms. Under test and observation, at present, Henderson has about 13,000 new iris plants. Among the newer colors he has produced in these flowers are an almost clear red, orchid shades, a sky blue, and a red and bronze combination.

IN ALL these experiments, thousands of plants must be grown and destroyed to obtain a handful of promising specimens. For example, out of a field of 2,000 iris, only four were selected for further use and the rest were burned. Again, of 5,000 zinnias, only ten were found fitted for further trial. The greatest skill is required in this process of selection and in the work of hybridization, or cross-breeding.

In the latter task, a touch of pollen taken from the stamen, or pollen-bearing organ, of one flower is placed on the pistil, or seed-bearing organ, of another. The seeds resulting from this artificial fertilization are carefully planted. When the hybrid plants bloom, only the ones that approach most closely a desired combination of qualities inherited from the two parents are saved. These are again crossbred and this process continues for several years until a new type of plant, with new qualities, has been evolved.

Probably the most difficult task of cross-breeding Henderson ever had was during his work with Muscat grapes. His goal was a new kind of grape, without seeds, with the flavor of the Muscat and ripening in July instead of in September or October, the time when these grapes usually appear on the market.

The first step was taking pollen from the flowers of a seedless grape. This he shook off by hitting the flower clusters against the edge of a saucer. The next day, this fine fertilizing dust was placed on the flowers of a Muscat vine. This was a tremendous task. In each Muscat cluster are about 2,000 flowers, each only a sixteenth of an inch across. In addition, a tiny cap fits over the pistil, covering the anthers, or pollen-bearing parts of the stamen, on every flower. Therefore, it was necessary to perform a delicate operation on each minute flower, removing the cap and anthers with a small pair of tweezers before applying the pollen. This was rubbed on the pistils which carried it downward, fertilizing the ovaries.

Four hours a day, day after day, this nerve-straining work went on. About 500 flowers in a cluster of 2,000 were treated. When the fruit from this crossing had ripened, about 5,000 seeds were saved and planted, first in a sandbox, then in individual pots, and finally in the vineyard.

Out of these 5,000 plants, 480 were selected for further experiment. They have been growing for nearly five years and have become huge vines. Last year, Henderson opened eight or ten grapes on every vine and found one vine with all seedless fruit and many with only a few grapes having seeds. The seedless vine bears large-size fruit with Muscat flavor.

About twenty-five of the 480 vines fruited last year. This year, with eighty-five percent fruiting, Henderson has found another completely seedless vine. The grapes from it are a golden color and possess the desired Muscat flavor. Since the ripening time of these grapes is several weeks ahead of the usual time for Muscats, they are expected to prove of great commercial value.

In his work with gladiolus, Henderson was aided in the task of cross-breeding in an unusual way. In his pact of California, the Egyptian Moth, a nocturnal insect almost as large as a hamming bird, is common. These moths are particularly fond of the nectar from gladiolus and flew from the common to the wild variety which he had planted side by side in his garden, carrying the fertilizing pollen with them.

While he was stilt at the Burbank gardens, he had begun his experiments with this scentless flower, seeking to give it a delicate perfume. Hearing of a wild gladiolus in South Africa, called the "Gladiolus Tristus," which gave off a delightful fragrance at night, he sent for seeds. These he planted in his Fresno experiment garden beside rows of the common variety of the flower. By cross-pollenating, as well as by permitting the night moths to assist in the work of fertilization, he produced a new flower which, with each successive generation, possessed more and more fragrance, a delightful went like the aroma of gardenias and orange blossoms combined.

ANOTHER accomplishment to which Henderson "points with pride" is his Abundance sweetcorn. It is a development from the Golden Bantam corn. The chief improvement in the new variety is the increase in the number of kernels. The Golden Bantam usually has only eight rows to the ear. By selecting seed from corn of this type which showed a tendency to more rows, and by repeating this process over a number of years, he has developed a new corn that has sixteen rows and a mach longer ear. At the same time, the kernels have retained their tenderness and high sugar content.

Someone has jocularly remarked that: "There is some good in everything, there being no bones in spinach." Henderson has produced another commendable quality, added attractiveness in color. By crossing Swiss chard with sugar beets, he has developed a new variety of greens with brilliant red stalks and red veins in the leaves. This coloring remains even after the chard is cooked adding to the attractiveness of the dish on the table. At first, the result of the crossbreeding was plants of innumerable color combinations in leaves and stalks. But rigid selection over several years produced a type which comes true from seed.

BESIDES its unusual coloring, the new plant, known as the Crimson Giant chard, is a profuse grower with unusually large leaves. Three or four plants, Henderson calculates, will supply an average family with succulent greens for a season. Instead of going to seed in three or four months, as formerly happened, the new chard develops seeds only once in two years.

Just before his death, Burbank was trying to produce a rose of unusual color and extreme fragrance combined with ability to stand heat and severe weather changes. Henderson's experiments with roses have been along these lines. He has a wild rose which he uses for hybridizing purposes, putting the varied colors of tame roses into the wild one. Among the colors thus far produced are a dark, velvet red edged with black; silver pink; orange; pure scarlet, and a yellow and bronze combination. Public taste in roses, during recent years has run to vivid, brilliant hues, and Henderson has endeavored to satisfy the demand.

Most of his experiments are carried on with a definite goal. Canners ask for a stronger skin, a sweeter flavor, or a larger size in a certain fruit. Henderson sets out to produce the desired improvements. Florists seek certain colors in certain flowers, Henderson works to supply them. But occasionally he makes an experiment without the slightest idea of what will result, "just to see what comes of it." One test of this sort is going on now. It is the union of the pepper, the potato, the tomato, and a yellow plant similar to the jimsen weed. All four belong to the same family. But what the combination will produce, no one can predict.

In his work, Henderson imports new plants and trees from many lands,—Australia, Siberia, South Africa, Japan, England, Turkestan, and elsewhere. From Africa, came a scarlet wistaria tree; from Chile, a giant trumpet vine that blooms three times a year; from Siberia, ornamental crabtrees, and from Japan, evergreen pears.

One of the strangest experiments he is carrying on is an effort to produce a peach with a pit flavored like an almond. Such a fruit-nut combination was first considered by Burbank many years ago. He attempted to cross the stoneless plums, the peach, the nectarine, or smooth-skinned peach, and the almond. Ordinarily, the peach and the plums do not cross. Burbank obtained one such hybrid, but it was not a success. It never bloomed.

HENDERSON believes it might have been successful in a warmer climate such as Fresno's. Sudden climatic changes often produce great differences in plants. The rhubarb, for instance, grew only in seasons in its native country, Australia. In California, it became an evergreen, producing the year around. At his Fresno farm, Henderson is grafting scions from stoneless plums onto peach trees to reduce the size of the pit and the thickness of the peach-stone before going on to the nest stage and crossing the peach and the almond. The final result, he hopes, will be a large and luscious smooth-skinned peach with an almond-flavored kernel.


HORIZONTAL rivers of air, moving rapidly in various directions through the stratosphere, were discovered by Prof. Auguste Piccard during his second ten-mile ascent above the earth in an air-tight globe last August. The discovery, following prediction of such high-altitude currents, is announced in a recent report by Max Cosyn, Prof. Piccard's assistant on the spectacular balloon flight over Switzerland and Italy. Its importance is great to sponsors of high-speed planes designed be travel in the stratosphere, where a pilot could take advantage of the air streams to add to his speed. Another interesting observation daring the latest Piccard flight was the absence of air pockets or eddies at the highest altitudes. At this writing, the data obtained regarding cosmic rays are still being checked and interpreted.


EXCITING news to fossil-hunters was the recent announcement of Barnum Brown, dinosaur expert of the American Museum of Natural History, of the outstanding discovery of the year by any expedition in this country. The Montana find was a complete skeleton of a dinosaur known as "horlitosaurus," a creature so rare that only a handful of bony plates have hitherto testified to his prehistoric existence. The newfound skeleton show's he was fourteen feet long, and seven feet wide. Heavy armor plates of bone covered him.