American Breeders Magazine 4(3): 169-174 (July 1913)

Chinese Cudrania, Closely Allied to Common Mock Orange, Promises to be Valuable if Its Size Can be Increased by Hybridization

One of the most interesting but little-known Chinese fruits which has been introduced to the United States during recent years is Cudrania tricuspidata, a representative of the natural order Moraceae and closely allied to the Osage Orange of the Middle West. Its fruit, although small (one to one and one-half inches in diameter), is sweet and eatable, and because of its hardiness the shrub can probably be grown throughout the southern half of the United States. If successfully crossed with the Osage Orange, the progeny offers promise of being a source of food for live stock in a wider region, while selection of the fruit itself should result in the establishment of a variety that would be well worthy of cultivation for its fruits.

The first introduction was made by E. H. Wilson, of the Arnold Arboretum, Boston, who secured the tree in Central China, where it is known as Che. More recently Frank N. Meyer, agricultural explorer of the Bureau of Plant Industry, U. S. Department of Agriculture, at Washington, has sent it in from Laoling in the province of Shantung, where it is called Tcho Sang, "wild mulberry." "It is a wild shrub," he reports, "sometimes growing into a small tree, and found in dry places. The leaves are used for feeding silkworms in times of scarcity of mulberry leaves. This plant makes a similar impression to the Osage Orange, but is of much smaller dimensions. It can be utilized in the drier parts of the United States as a hedge plant around gardens, as a fence material on farms, and, in the milder, semi-arid sections, for bank-binding. It is very thorny and can therefore serve very well for hedge purposes." There are several other species with edible fruits.

Specimens sent out by the Arnold Arboretum have already fruited at Augusta, Georgia, where those who have seen the tree have formed a high opinion of its possibilities. R. C. Berckmans, of the Fruitland Nurseries, writes : "The trees which we have are from seed planted about five years ago. In 1912 we had the first fruit. The trees were then from two and one-half to four inches in diameter, and 10 to 12 feet in height.

This fruit, resembling the Osage Orange of the United States in appearance and closely related to it, is sweet and edible. It grows, rapidly even in poor soil and a dry season. It is already being tried m Georgia as a stock food, and has proved very hardy. If hybridized with the American Osage mock orange, it would probably have a still greater range and make a larger fruit and tree.

"R. O. Lombard, of this county, who is largely interested in hog growing, thought the tree had merit as hog food. Last season we gave him all the trees we had except three. The three which we have in our nursery were cut to the ground, and have made about 10 feet of growth this season. Mr. Lombard also cut his trees back, and tells me that they made about four feet of growth. They would have made more but from the fact that he is in a very sandy section and has had a drought more or less through the entire season. The trees we have here have withstood some severe weather during the past five winters without injury.

"From the above data we would consider this tree rather a rapid grower, and one that will stand very low temperatures — probably zero and maybe lower. It can be readily propagated from seed or roots. I have noticed in the nursery rows where the trees were dug last season that quite a number of small ones have come up from the roots, and some at least 20 feet from where the original tree stood. As to its real merit as stock food we have as yet no real data."

The correspondence of these facts with those furnished by the mock or Osage orange (Toxylon pomiferum Raf., Maclura aurantiaca, Nut.) is striking. This tree, which is native of the region between eastern Kansas and northern Texas, sometimes reaches a height of 30 to 50 feet, but is best known in hedge form. It is hardy as far north as Massachusetts ; grows readily and rapidly either from seed or roots, is a voracious feeder and not particular about soil, bearing its green, woody and inedible fruits, four or five inches in diameter, profusely. Its hard wood is valuable for fence posts. By making hybridizations between these two allied genera, horticulturists over a large area will have a chance to get some exceedingly interesting results.

Although the cross has not actually been performed in the United States, so far as the record shows, it is entirely practicable, for it was made in France by the late Edouard Andre, editor of La Revue Horticole, and described by him in that journal, under the name of Macludrania hybrida, in 1905, page 362. He says:

"In January, 1896, I made the readers of the Revue Horticole acquainted with a new variety of Maclura aurautiaca, fortuitously produced in the garden of Mme. Helie of Bléré (Indre et Loire), and which I named Madura aurantiaca inermis. In this variety, the spines which arm the branches of this species had entirely disappeared. Moreover, the vigor of the plant is superior to that of the type. It is another beautiful tree added to our collection of ornamentals.

"I added that as the subject was female (it is well known that M. aurantiaca is dioecious), I had the idea of fecundating it by pollen from a male specimen of Cudrania triloba which I possess at Lacroix and which, each year, in June, is covered with staminiferous globules. It was M. Guy of Bléré who undertook this operation and succeeded in obtaining fertile fruits. The seeds were sown and I obtained half a dozen plants which grew vigorously.

"It is this new hybrid which I now present to our readers.

"As the two genera are distinct, although related, I have employed, to create the name of the bigeneric hybrid, the formula which consists in taking the beginning of the first name and the end of the second. We have thus Macludrania, with the qualificative hybrida.

"The young plants which were grown from these seeds, and which are today in their eighth year, are now beginning to be clearly characterized.

"Until last year, I let them grow freely in their bushy form, which is now being modified by the development of strong shoots which tend to gain predominance over the weaker ones. Pruned specimens have a well-marked trunk, as large as a broom-handle. They have rather the appearance of the Cudrania, with its low stature, than the arborescence of Maclura aurantiaca. They are uniformly spiny and present no spineless branches, like their mother — which, however, was only an accident in the species. The form and foliage of all the specimens I have are identical. None of them has yet flowered, so I cannot tell whether they are of different sexes.

"The description of Macludrania hybrida is as follows:

"A small tree reaching (today) a height of three or four meters, at first bushy, then forming an erect stem with yellow, fissured bark, that of the preceding year being gray-green with transversal grayish-green corrugations ; the branches of this year's growth light green at the ends, assuming a violet tint, as well as the upper parts of the petioles. Spines hard, woody, short, straight, at right angles to the axils of the leaves, very sharp, those at the tops of the branches dark brownish-red, almost black. Leaves glabrous, alternate, with milky sap, not polymorphous, slender petiole of a violet shade on top, short (two to three cm.) ; 15 cm. long and 10 wide, oval, longitudinally acuminate, with very smooth, varnished surface, numerous small veins, the primary ones acutangular, sub-opposed at the base, all slightly depressed below the surface at the ends, prominent, pale and puberulent towards the base, accompanied, at the swollen base of the petiole, by two very minute, scarious bracts. Flowers unknown.

A common hedge plant, native from Kansas to Texas. Its fruit reaches a diameter of five inches, but is woody and, except in rare instances, not even eaten by live stock. As the tree is hardy, a hybrid of this native form with the edible Chinese Cudrania may give an edible fruit that can be grown over a wide range in the United States even under adverse conditions of soil and rainfall.

"This hybrid differs from Maclura aurantiaca by its weaker growth, its adult branches smaller and dark brown, its spines, at right angles to the axils of the leaves like Madura but more numerous, closer together, shorter, very sharp and woody, those at the top reddish brown, almost black in autumn. It is more like Cudrania triloba in the slenderness and dark color of its adult branches, and differs from it in its short spines, not decurvent, the stipules of its young leaves shorter, the limbs not subcordiform at the base and more longitudinally acuminate, the absence of three-lobed leaves in its young growth. We will see later if these differences are accentuated in the organs of reproduction and in the leaves of the flowering branches.

"But it is curious to notice that the product of these two genera is much nearer the father than the mother, and we have every reason to suppose that the characteristics of the Cudrania will retain their predominance in it.

"The polliniferous tree, the C. triloba in the park at Lacroix, today measures eight meters in height, with a head seven meters in diameter. Its trunk is two meters long and 65 cm. in circumference at a meter from the ground. It is certainly one of the most vigorous specimens which exist in France. It now is a tree of great elegance, its lustrous foliage is never attacked by insects, and its innumerable little globes, the male flowers, pale yellow, almost creamy, exhale a sweet perfume during the fortnight (from June 15 to July 1) when they spread their pollen abundantly before falling to the ground. The tree was introduced from China to the Museum (Paris) in 1862."

It is necessary to note that the specific name triloba which M. Andre used has been set aside by the earlier one of tricuspidata. Although the French experiment does not give conclusive evidence as to the range of these trees, it is encouraging enough to make wide experiments at once desirable in the United States.