Popular Science Monthly/Volume 23/July 1883/Selection in Grain-Growing
|SELECTION IN GRAIN-GROWING.|
THE principle of selection has long been appreciated by stock-breeders, and they have largely profited by the application of its teachings. As applied to the growth of cereals it has not found a very wide acceptance, not having had time to force itself on the attention of the average farmer. The founder of the practice of selecting grain for seed is Major Hallett, F. L. S., Brighton, England. In 1861 he planted ten grains of wheat, from a variety known there as Bellevue Talavera wheat, which up to that time had been sown as a spring wheat, and was declared to be quite incapable of withstanding the frost of winter. Nine of the ten plants from these grains were killed by the severe frost, but the other plant, although from the same ear, remained as healthy and vigorous as any of the winter varieties of wheat by their side. From this surviving plant seed has been selected and grown year after year as a winter wheat. Close observation shows that in the cereals, as throughout nature, no two plants or grains are exactly alike in productive power, and hence that of any two or greater number of grains or plants one is always superior to all the others, although the superiority can only be ascertained by actual field tests. It may consist in several particular characteristics, as power to with-stand frost; prolificness; size and character of ear; size, form, quality and weight of grain; length and stiffness of straw; powers of tillering; rapidity of growth; and many others.
Throughout continued observations and experiments, extending over twenty years, the grower has found only three instances recorded in which there were two ears on a plant containing an equal number of grains, and one of these related to the Bellevue Talavera wheat, which must be considered quite exceptional as to variation. In both the other instances there was only a low stage of development, the equally finest two ears of each plant containing but 59 and 49 respectively. In every case where the plant presented an ear containing GO grains and upward the next best ear was of less contents than the finest one. In twenty such instances taken consecutively and without omission, and referring to seven varieties of wheat, the average difference between the contents of the first and second ears was seven and a half grains. The difference in four of these instances was only one grain, but in other four it amounted to from seventeen to nine-teen grains. The superior productive power of a grain over that of another may consist in a greater number of ears upon the plants it produces, or in their individually containing a greater number of grains.
During these investigations no single circumstance more forcibly illustrated the necessity for repeated selection than the fact that, of the grains in the same ear, one is found to excel greatly all the others in vital power, as in the case of the Bellevue Talavera. The original two ears together contained 87 grains; these were all planted singly. One of them produced ten ears containing 688 grains, and not only could the produce of no other single grain compare with them, but the finest ten ears which could be collected from the produce of the whole of the other 86 grains contained only 598; yet supposing that this superior grain grew in the smaller of the two original ears, and that this contained but 40 grains, there must still have been 39 of these 86 grains which grew in the same ear. So far as regards contents of ears.
The next year the grains from the largest ear of the finest plant of the previous year were planted singly, twelve inches apart, in a continuous row; one of them produced a plant consisting of fifty-two ears; those next to and on either side of it of twenty-nine and seventeen ears respectively; and the finest of all the other plants consisted of only forty ears.
The following are the chief points of the standard in the order of their importance, but all have to be duly considered:
1. Hardihood of constitution.
2. Trueness of type.
3. Quality of sample.
5. Power of tillering.
6. Stiffness and toughness of straw.
7. Earliness of ripening.
The system of selection here pursued is as follows: A grain produces a plant, consisting of many ears. Then are planted the grains from these ears in such a manner that each ear occupies a row by itself, each of its grains occupying a hole in this row, the holes being twelve inches apart every way. At harvest, after the most careful study and comparison of the plants from all these grains, the finest one is selected, which is proof that its parent-grain was the best of all, under the peculiar circumstances of that season. This process is repeated annually, starting every year with the proved best grain, although the verification of this superiority is not obtained until the following harvest.
The subjoined statement will illustrate this system of selection, as the facts given are due to its influence alone: the kind of seed, the land, and the system of culture employed were precisely the same for every plant for four consecutive years; neither was any manure used, nor any artificial means of fostering the plants resorted to.
The following table shows the character of each additional generation of selection:
|1857||Original ear||4⅜||47||. .|
|1860||Ears imperfect from wet season||. .||. .||39|
Thus, by means of repeated selection alone, the length of the ears has been doubled, their contents nearly trebled, and the "tillering" power of the seed increased fivefold.
The following table gives similar increased contents of ear obtained in three other varieties of wheat:
|KIND OF WHEAT.||Grains|
|45||Original Red commenced in 1857||123|
|60||Hunter's White commenced in 1861||124|
|60||Victoria White commenced 1862||114|
|32||Golden Drop commenced in 1864||96|
It was supposed by ancient writers that the powers of grains differed in relation to their positions in the ear. This Major Hallett investigated in 1858, by planting the grains of ten ears on a plan showing their several positions in the ear. The only general result, among most conflicting ones, was that the smallest grains, those most remote from the center of growth, exhibited throughout, most unexpectedly, a vigor equal to that of the largest; and that the remarked worst grains, in one or two instances, did not by any means fall so far short of the good ones as had been expected. Frequent trials have also been made of the comparative power of large and small, plump and thin grains, and, in the case of oats, which produce a small grain attached to a large one, trials as to their respective powers—with uniform results, viz., that, in good grains of the same pedigree, neither mere size nor situation in the ear supplies any indication of the superior grain.
Very close observation during many years led to the discovery that the variations in the cereals which Nature presents to us are not only hereditary, but that they proceed upon a fixed principle, and from them has been educed the following law of development of cereals:
1. Every fully-developed plant, whether of wheat, oats, or barley, presents an ear superior in productive power to any of the rest on that plant.
2. Every such plant contains one grain which, upon trial, proves more productive than any other.
3. The best grain in a given plant is found in its best ear.
4. The superior vigor of this grain is transmissible in different degrees to its progeny.
5. By repeated careful selection the superiority is accumulated.
6. The improvement, which is at first rapid, gradually, after a long series of years, is diminished in amount, and eventually so far arrested that practically a limit to improvement in the desired quality is reached.
7. By still continuing to select, the improvement is maintained, and practically a fixed type is the result.
Thin Seeding with Selection.—Let us discuss what is possible by a combination of thin seeding with selection. In order to do this, we must look at the present modes of cultivating the cereals. Confining ourselves for the moment to wheat alone, we know that from two to five bushels per acre are sown. The bushel of ordinary wheat contains 700,000 grains and more, and, taking two bushels per acre as the quantity sown, we have about 1,500,000 grains per acre. Major Hallett has counted at harvest the number of ears upon a quarter of an acre of wheat (drilled 20th of November with one and a half bushel of seed per acre, and which proved an exceptionally heavy crop of fifty-six bushels per acre), and the number of ears found was 934,120 per acre, or not so many ears as the grains sown. Here it is evident, from the number of grains sown, that either the natural powers of tillering could not have been exercised, or that the greater part of the seed must have been sown uselessly. Doubtless some of the grains did produce more than one ear, but this only makes the case still worse for the remainder. Not only was the number of ears below that of the grains sown, but each ear was but the stunted survivor of a struggle for existence. A high authority has said that, if a square yard of thickly-sown wheat be counted in spring, and the supposed number of ears then recorded, it would be found that ninety per cent of them would be found missing at harvest. Beyond all question, in thickly-sown wheat, very many of what appear as stems in the spring die away before harvest, and have thus grown not only uselessly, but in the struggle for existence have starved and stunted those which ultimately came to ears.
In ordinary English crops the number of ears produced per acre being taken as about 1,000,000, and the crop as 34 bushels, we have, at 700,000 grains per bushel, 23,800,000 grains per acre, or an average per ear of only 23 to 24 grains; and, if more than 1,000,000 ears per acre be claimed, it must be at the expense of their contents. Five imperial pints (= 6·1 American measure) of wheat per acre planted in September, 12 inches X 12 inches, gave 1,001,880 ears per acre, or 67,760 ears in excess of those produced on the other side of the hedge from l2 bushel, or more than thirteen times the seed. Again, 6·1 pints (American measure) of wheat planted 12 inches X 12 inches, October 17th, gave 958,320 ears per acre; and planted similarly, October 4th, 966,792 per acre; while one bushel, planted October 15th, gave only 812,160.
Two plants of 24 ears each gave 1,911 and 1,878 grains, or 79 per ear; 20 ears per foot, at 48 grains only per ear, would produce 88 bushels per acre. All the 1 conditions of time and space being fulfilled, we can obtain from a single parent-grain as many ears as are ordinarily obtained from twenty grains, with this most important advantage, viz.: these ears being produced from plants which have attained (or nearly so) perfect development of their growth, contain more than double the common number of grains, and their contents may be largely increased by the continued annual selection of the most vigorous parent-grains. These small quantities may be drilled on a large scale in the following manner: The object is to insure perfect singleness and regularity of plant, with uniformity of depth. The two latter may be obtained by the drill, as may the former also by adopting the following plan: The seed-cups ordinarily used in drilling wheat are so large that they deliver in bunches of grains, consisting of six or seven, which fall together within a very small area, from which a less produce will be obtained than if it had been occupied by a single grain. The additional grains are thus not only wasted, but are positively injurious. By using seed-cups which are only large enough to contain one grain at a time, a stream of single grains is delivered, and the desired object, viz., the depositing of grains singly, at once attained. The intervals in the rows will not be exactly uniform, but they will be sufficiently so for all practical purposes. The width of these intervals will, of course, depend on the speed with which the seed-barrel revolves, which can be regulated at will by adjusting the gear which drives it. By this mode of drilling, the advantage of the "broad-cast" system is obtained (equal distribution), as the rows may be close together, and the grains as thin in the rows as may be desired.
The crop should be hoed, as soon and as frequently as possible, with a horse-hoe. If the seed has been sown early, this should be done in the autumn, as it causes the plants to tiller and occupy the whole ground before winter sets in. It is essential to the success of thin seeding to keep the land perfectly free from weeds during the growth of the crop.
Now, what are the advantages of Major Hallett's system? A bushel of pedigree wheat (original red) produced from single grains, planted 12 inches X 12 inches, contains about 460,000 grains, while a bushel of ordinary wheat contains 700,000 or more grains. Therefore, in two crops consisting of exactly the same number of grains, the crop from thin seeding would be upward of 70 bushels against 46 bushels per acre. Again, a bushel of pedigree barley, produced from grains planted singly, contains 390,400 grains; while a bushel of ordinary barley contains upward of 550,000, or, in two crops of equal numbers of grains, the one would be 55 bushels, the other 39 bushels, per acre. Thus in the increased size alone we get an increased crop of forty to fifty per cent.
The saving of seed from such a practice is immense. The wheat area of the United States is not less than 40,000,000 acres, and the average seeding is very much higher than two bushels per acre. But, if these figures be taken as a basis, we shall not err on the wrong side. To plant grain at the rate of one berry to each square foot would be equal to 43,560 grains per acre of 4,840 square yards, or less than two English quarts. This shows that the farmers of the United States have it in their power to reduce their consumption of seed-wheat from 80,000,000 bushels to 2,500,000. Good seed-wheat ought certainly to be worth a dollar a bushel out West, and is worth very much more in the East; but on this showing we have a possible saving of $77,500,000 in seed only for the wheat-crop alone. One dollar and a half per head of the population is worth attention.
The roots of wheat sown in August become by the middle of October so developed as to render it quite safe from lifting by the frost, and attacks of wire-worm would be almost unknown. If winter wheat were all drilled by the 10th of September, the entire fall would be at the farmer's disposal for clearing the land and sowing spring crops early. The crop could not become winter-proud, or be laid by the summer rains. The harvest would be from two to three weeks earlier. The harvest being over at least a fortnight earlier, would be of immense advantage in clearing the land. Seasons are frequently most unfavorable to late-sown cereals, but they are scarcely ever so to early-sown ones. On well-farmed lands, on the common practice, the average contents of the wheat-ears must be from 20 to 30. Were it grown on Major Hallett's system, the average contents would be, at the very least, from 40 to 60, and far more likely from 60 to 90; for under such a system so small an ear as one of 40 grains is quite the exception. And this increase of the contents of the ears would be obtained without any diminution of their number; the crop, in fact, would be doubled where now fairly good farming yields 30 bushels to the acre. These promises are not illusions, since a good many men in European countries, and in the United States also, have accomplished great results in agriculture by the application of commonly accepted principles of science. Major Hallett has himself grown 216 bushels from three acres with one bushel of seed, or 72 bushels to the acre; and over a whole field 82 bushels of barley, weighing 57 pounds to the bushel, from only two gallons of seed per acre.
In reference to the point of time of sowing, it must be borne in mind that the rate of growth for wheat during the different months in England is as follows:
|Wheat sown on||September 1st||comes up in||7||days.|
|""||October 1st||In a mild
Taking this as the relative rate of wheat-growth, when it is up, then wheat which is up on the 1st of September makes in the first fifteen days of that month a growth equal to that of the whole of October; in the next ten days a growth equal to that of the whole of November; and, in the last five days of September, a growth equal to that of the first twenty days of December; or, in other words, wheat up on September 1st has a double autumn for growth before winter sets in; and, indeed, the case is in reality much stronger than this, for, if winter were to set in early, there would be for wheat sown at the end of October little or no autumn growth above-ground. The importance of every day (especially the early days) of September growth can not be overrated. To illustrate this, Miss Hallett made two very accurate drawings, which her father produced publicly. They were taken on December 30th, of two plants of wheat, each from a single grain, one of which was up on September 1st, the other on September 19th, and had thus lost the growth (after having come up) of the first nineteen days of September, the development of the earlier being double that of the later. These facts clearly point to the necessity of sowing in August. Nature, too, in shedding the grain in August, seems to indicate it as the proper time, or rather as a not unfit time, or the species would not be perpetuated. Within the present century it was the custom of many English farmers to go to wheat-sowing whenever it rained during harvest.
In determining the space to be assigned to each grain, we must deal with seed the result of continued selection, for the vital powers of the different grains of ordinary wheat are so very unequal that it would be impossible to fix upon any uniform distance. In planting grains of wheat in August, singly and twelve inches apart each way, all the requisite conditions of time and space seem to be best fulfilled, as will be seen further on. Wheat has been planted September 9th, 9 inches X 9 inches, and produced at the rate of 108 bushels per acre. It must be borne in mind at all times that it is a matter for mature study and judgment to correctly apportion the quantity of seed to the time of sowing, and to all the existing surrounding circumstances. A large quantity of seed sown early is just as much opposed to reason as a small quantity of seed sown late, and in fact more so, as in the first case it will become winter-proud and can not succeed, while the season may be such as to enable the last to do so. As a general basis, the drilling of wheat on a large scale might be conducted between the end of August and the 10th of September, at the rate of two to three gallons per acre; for each week later to the end of September, a gallon extra. When observing the unimpeded growth of cereals, there is seen to exist a striking variation in their modes of growth and powders of production. The superiority of some individuals over others is so marked in various ways as to lead irresistibly to the conclusion that it must be hereditary, and on this fact the whole argument for selected seed-grain rests.
Let it not be supposed, from what has been stated, that the use of artificial fertilizers is sought to be prejudiced. On the contrary, if improvement can be secured without them, it will be immensely greater when aided by them. But while the purchase of good seed of pedigree stock in small quantity, though the farmer bought it at six dollars (Major Hallett frequently obtains five), would be a very economical proceeding if he does not use more than two gallons, the cost of which would only be one dollar and a half per acre, whereas buying common seed at one dollar, and using two to three bushels, involves a greater outlay. Therefore, in proposing this reform, it will be seen that it does not mean spending more, but less, on seed. The weeding, if done properly, may cost two dollars per acre; and if, after this, the grower has any money to spend on fertilizers, let him invest by all means. As a general rule, it may be confidently asserted that what would be saved in the outlay for seed would pay the cost of horse-hoeing.
Considering how rapid is the improvement of the process of selection during the first five years, its effect on the wheat-crop of the country would be enormous. If we take 500,000,000 bushels of wheat as the present product (which is much less than it is), then doubling the crop and adding at the very least fifty per cent improvement in quality to the grain, we should obtain an increase of about $750,000,000, without bringing an additional acre into cultivation. I have not said much of the effect on the corn-crop, but on a crop of 1,750,000,000 bushels, at an average value of 38 cents, would, if but fifty per cent increase, in five years could be realized on 27·5, be astounding. Today, the area in corn is not less than 65,000,000 acres; 12·50 bushels increase, at 40 cents per bushel, would be five dollars an acre, or $325,000,000: $1,075,000,000 of additional food in the short space of five years would give a new impetus to the milling trade in this country, and the hog-business would grow with a rapidity out of all proportion to its past career. Neither steel nor electricity can promise anything so great in so short a time, and no reform accomplished in this century will be able to measure this one.
Who will be the first to carry out such a scheme? In the Washington Department of Agriculture and in several other parts of the country, pedigree cereals have been used, but the results have not been taken much advantage of. The experimentalists of the State College farming-stations are especially qualified to lead in so important a work. The time is not far distant when intensive rather than extensive culture must be the rule of American farming. Already, in the East and in the South, men are finding it pays better to cultivate 100 acres well than 300 acres carelessly. When the hunger for large areas abates, we may hope to see attention paid to better cultivation. The toil and misery, disappointment and mortification of skimming broad acres for meager results must give place to farming for profit. The change, when it comes, will be aided to some extent by professional guides and public men, but the foundation for it is within. The farmer is a near neighbor of hard facts, and living in days when everything is questioned, and nothing is taken for granted—when every institution in the land has to make good its claim to existence by the results produced—he is not likely to be deceived, or to grab any longer at the shadow for the substance. His wealth and happiness consist not in the number of his acres so much as in the principles of his farm practice. He will discover, as many of his confrères have already done, that the future of American agriculture will be determined by the extent to which fundamental truths of science are applied.