Some Problems of Method pp. 5-13 (1952)
Ivan Michurin

In what respects do my methods of work differ from the methods employed by other specialists

Before proceeding to discuss the difference between my methods of work and those used by other specialists, it is necessary to know where and who in the U.S.S.R. besides myself has been occupied with the selection of fruit frees and shrubs and has produced any new varieties of these plants. With the exception of the scant works of Kopylov, Spirin, Bedro and Professor Kashchenko, each of whom has produced three or four new varieties of plants of third-grade quality, I do not know of a single horticulturist working to produce new varieties on a scale worth mentioning. Therefore, I cannot explain the difference between my methods and those of other workers in the same field, so far as the breeding of apple trees and pear trees, cherries, plums, apricots, etc., is concerned. As to the methods employed by foreign horticulturists, their having been elaborated in the conditions of climate and soil entirely different from those of the U.S.S.R., makes them inapplicable in our country in most cases.

Furthermore, as the readers probably know, neither in any of the West-European countries, nor in America, are there any such institutions at the present time, working exclusively on the production of new orchard varieties of fruit trees and small-fruit shrubs. Perhaps some of the readers will not agree with my statements. I am not going to dispute such opinions for the reason—if for no other—that many agriculturists in their approach make no distinction between annual herbaceous plants and perennial fruit trees. Actually there is an immense difference between these plants in the length of time during which they are subjected to the action of environmental factors that affect the constitution of the newly developing plant organism of every new variety. Very great indeed, I repeat, is the difference between the complete life cycle of, say, Mendel's pea and that of any variety of apple, the development of which may continue until the age of twenty or thirty years. During this time the entire structure of the hybrid is often changed beyond recognition under the prolonged influence of diverse environmental factors, with some of its properties vanishing so completely that no trace of them is left, others developing, and with still others becoming manifest. Besides, sport variations displaying properties of some of the grandparents of the parental plants likewise occasionally occur.

Many people are inclined to consider that the difference between my methods of rearing the plants and the general rules of horticulture lies in the fact, that, when laying out a nursery, I never use deep turnings of the soil, never give the young hybrid plants any fertilizers, plant these hybrids very densely, etc. My first answer to these criticisms will be that it is one thing to run an orchard with already existing varieties of plants—here there can be no denial of the necessity to keep up a high level of culture in rearing the plants—and quite a different thing to produce and to rear new fruit-plant varieties, and these two things should never be confused. I have come to the Spartan regimen of rearing the plants after having thoroughly studied the life of fruit trees and small-fruit shrubs belonging both to the wild species growing in our forests and to the cultivated varieties bred in our orchards. The difference in longevity between the first and the second is very significant. Forest plants live in general four times as long as cultivated ones and, what is most interesting, the better the treatment the plants are given, the shorter becomes their life span. At the first superficial glance the main cause of this phenomenon appears to be the more rapid exhaustion of the plant organism as the result of its fruit bearing being intensified by culture. But is that quite so? Don't we see in our forests wild-growing apple trees and pear trees yielding abundant crop every year and living more than two hundred years, while in our orchards they barely reach the age of fifty? For example, apricots and peaches grown in orchards rarely live over fifteen to twenty years, whereas in the forests of Manchuria and the Caucasus the same species attain the age of seventy and eighty. Even plantations of black currant and blackberry in our orchards get exhausted and have to be renewed and transplanted to a fresh site every eight or ten years, while in the forests black currant lives and yields abundant crops of large berries for almost a hundred years, remaining in the same place all the time. On viewing this phenomenon from the purely materialistic standpoint, it becomes evident that the cause of the shorter life span peculiar to all these coddled "bourgeois" of the plant world grown in our orchards is the loss of the capacity for "self-activity" in cultivated plant organisms. This is the result of the constant interference of man—lasting for hundreds and thousands of years—who provided these plants with ready conditions of comfort thus hoping to secure intensified fruit bearing. It is for this very reason that the majority of cultivated plants, having lost their property of self-activity, can no longer do without the care of man.

O. F. Cook (1909) observed this coherence of characteristics in cotton hybrids.

Already at the very beginning of my work in horticulture I observed that the hybrid seedlings grown on better soil—such as was fertilized and turned over—were by far the inferior in their resistance to all kinds of adverse climatic conditions when compared with the seedlings of the same hybrids grown on unfertilized sites with sandy soil; true, among the former a greater number deviated in structure towards the cultivated form. During the first decade of my work I still had doubts about the necessity of altering the regimen in rearing hybrid seedlings in the sense of affording them a better opportunity to develop the capacity for self-activity. I, naturally, supposed that any severe treatment in rearing these seedlings despite the culture properties inherited from the parent plants, would result in the appearance of wildings only, and in their incapability of producing the large-sized fruit of cultivated varieties. But fortunately it so happened that a few hybrid seedlings reared under relatively severe conditions gave large fruit of the finest quality on the sixth year after their germination, whereas all the coddled specimens raised in the best conditions were all destroyed by frost. I was therefore compelled to transfer my entire nursery to another site with a more meagre soil, and I did it without any hesitation. It was a venturesome matter to transfer the entire nursery, but later on it proved to have been justified and gave good results. Now this is where the difference lies between my methods and those of other horticulturists. Further, at the beginning of my work I used to cross the best foreign varieties of fruiters with our hardy local ones, but later such hybridization turned out to be a serious mistake, and it became evident that some different principle of choosing parents must be adopted.

The reason for that was, that when our hardy local cultivated varieties were pollinated with the pollen of the best foreign varieties, hybrids were obtained in the vast majority of which characters peculiar to our varieties proved to be dominant; subsequently these qualities developed, while the properties of the foreign varieties failed to manifest themselves and remained in a latent state. This was due to the fact that the hybrid seedlings were grown under the conditions of soil and climate habitual to our varieties. Thus, for example, although the fruit of hybrid pears had a fine taste, they were, however, small and ripened in summer. Both these features are peculiar to our Russian varieties of pears. In order to avoid the undesirable results of such unsuccessful combinations of mates, I began using as the hardy components for the crosses forms from very distant localities (in this particular case from the Far Eastern Territory of the U.S.S.R. and from Manchuria). By fertilizing these hardy forms with the pollen of the best foreign varieties, I succeeded in attaining an equal participation of both parents in the hereditary transmission of their properties to the hybrids, since they were now to the same extent deprived of the habitual environmental conditions of their native localities. Still another important advantage of such hybrids deserves being especially mentioned. They are all distinguished by their outstanding capacity for adaptation to environmental conditions of a new locality. So I rear hybrid seedlings without deep turnings of the soil, and without any fertilizers until the first appearance of fruit-buds. Only then do I give them some liquid fertilizer and cover the soil right under the young plant with a layer of fresh manure to obtain better-formed and larger-sized fruit. The layer of manure also affords some protection against over-drying of the soil. I plant the seedlings rather densely. After the first three-four years of bearing, when the new variety has already fully attained stability, some cuttings are taken from the mother-tree for the propagation of the new varieties by grafting on stock. If some defects in the hybrid's qualities are revealed after the onset of bearing, at times, although by no means in every case, some of these defects can be either partially or entirely removed by the expedient choice of various kinds of stocks or even partly by grafting as mentors cuttings taken from some other varieties. As for the origin of new species of plants, they appear rather rarely as a result of intergeneric, sometimes also of interspecific, hybridization. Similar phenomena arise by mutations, as well.

Some of the excursionists visiting our institution their number reaches five thousand every year at times ask me such questions: "Why is it necessary to produce new and improved varieties, when we have plenty of our old varieties?" I have to repeat to such naive persons what I have written time and again as far back as forty years ago in many of my articles: in nature the forms of life are not frozen and fixed; life is incessantly moving and continuously changing, and all living creatures that for some reason have come to a standstill in their development are inevitably doomed to extinction. Much of what seemed of old to be the best in its perfect adjustment to conditions of life that prevailed in the past, nowadays proves to be unfit and must be replaced. The same holds true with respect to our old varieties of fruit plants, most of which in the old days, when labour used to be gratuitous or cheap, were more or less suitable for commercial cultivation; in our days they are not only unworthy of being cultivated, but are a pernicious litter contaminating our orchards. Moreover, many of our old varieties have already lost their fine qualities or, as they say, "degenerated" and must give place to young new varieties.

I shall conclude this article by saying that the work of qualitatively improving fruit-plant varieties is of colossal importance for the future life of all mankind. That is why this activity must be unceasingly promoted and the necessity of working in this field must be impressed by all means into the minds of the entire population of the Soviet Union.

[CybeRose note: Michurin dies in 1935. The translation of this booklet was published in 1952. I don't know when it was first published in Russian.]