Concrete silos; their advantages

Preface

In this volume the author has attempted to bring together everything of value pertaining to the latest concrete silo construction. His investigation of the subject has led him to believe that there is a demand for such a book. While there is a large mass of literature on concrete silos extant, practically every piece of such printed matter is prepared with special emphasis on some particular type of construction, or on some particular phase of the subject.

This volume is an attempt to bring together all the best things in this scattered literature, m'aking it, so far as possible, a complete compendium of concrete silo construction. For this purpose the author has drawn freely upon bulletins of the various cement companies and of the Association of American Portland Cement Manufacturers, as well as upon publications of the State Agricultural Experimental Stations, and the literature of the comj^anies promoting various patented systems.

The demand for the book, even before it has appeared from the press, has been so gratifying that it is expected another edition will be necessary at an early date. The author will therefore be pleased to have readers advise him of any errors, inaccuracies, or omissions which they find.

E. S. HANSON.

Chicago, Oct. 15, 1915.

Contents

Page

Chapter I. Why Build a Silo o

II. What a Good Silo Should Be 25

III. How Concrete Meets the Eequirements 30

IV. Advantage Over Other Kinds of Silos 37

V. Size and Shape of a Silo 49

VI. The Different Types of Concrete Silos 56

VII. The Foundation of the Silo 59

VIII. The Monolithic Silo 63

IX. The Polk System 73

X. The Monsco System 79

XI. The Eeichert System 84

XII. Other Monolithic Systems 89

XIII. The Pit Silo 97

XIV. The Metal Lath Silo 102

XV. The Concrete Stave Silo 125

XVI. The Concrete Block Silo 140

XVII. Doorways, Doors, Eoof s, etc 157

XVIII. How to Increase the Silo Business .165

Catalog Section 175

CHAPTER I

Why Build a Silo?

The silo is not a fad. It has proven its right to a place in any intelligent scheme of agricultural economics, and it has therefore come to stay.

Coming first into existence as a mere hole in the ground, the silo has developed into a structure on which it is worth while to expend engineering ability and architectural skill. Many things have been attributed to Ca?sar and his strategists as the result of military necessity in the prosecution of his famous campaigns. Some of these are recorded in his own Commentaries, while others have perhaps a less stable historical foundation on which to rest. Our reading of the Seven Books is too far in the past to allow of a definite statement as to whether the famous general himself records the iwe of pit silos for the preservation of forage along his lines of march ; but such have been attributed to him, and the statement sounds plausible, at any rate.

The silo has been likened to a giant fruit jar. Apparently this idea, too, is not a new one, for it is stated that the early Egyptians, many years before the Christian era, put a part of their crops in large stone jars for preservation, covering them as tightly as possible to exclude the air. The Mound Builders and other

Iprehistoric tribes adopted similar expedients, as is proven by the relics which are unearthed from time to time, while some of the barbaric tribes of the present day build circular bins of interwoven reeds and plaster them on both sides with clay, with a thatched roof for a cover.

The following reasons for the popularity of silage are given by T. E. Woodward, of the Dairy Division of the U. S. Department of Agriculture :

(1) Silage is the best and cheapest form in which a succulent feed can be provided for winter use.

(2) An acre of corn can be placed in the silo at a cost not exceeding that of shocking, husking, grinding and shredding.

(3) Crops can be put into the silo during weather that could not be utilized in making hay or curing fodder; in some localities this is an important consideration.

(4) A given amount of corn in the form of silage will produce more milk than the same amount when shocked and dried.

(5) There is less waste in feeding silage than in feeding fodder. Good silage properly fed is all consumed.

(6) Silage is very palatable.

(7) Silage, like other succulent feeds, has a beneficial effect upon the digestive organs.

(8) More stock can be kept on a given area of land when silage is the basis of the ration.

(9) On account of the smaller cost for labor, silage can be used for supplementing pastures more economically than can soiling crops, unless only a small amount of supplementary feed is required.

(10) Converting the corn crop into silage clears the land and leaves it ready for another crop sooner than if the corn is shocked and husked.

r oncrete Silos

Another and even longer list of advantages of ensilage is given by the experts of the Missouri Agricultural Experiment Station. They are as follows :

(1) Harvesting corn as silage saves from 35 to 40 per cent of the crop that would otherwise be wasted.

(2) Silage adds palatableness to the ration.

(3) Silage adds succulency to the ration.

(4) Silage serves to keep the digestive tracts of animals in good condition.

(5) Silage replaces high-priced hay.

(6) Silage serves to cheapen the ration.

(7) When silage is fed, more feed is eaten, hence more manure.

(8) The man who feeds silage uses a manure spreader.

(9) The feeding of silage means more intelligence in feeding operations.

(10') The feeding of silage results in more intelligence in other farm operations.

(11) The man who feeds silage will feed with it concentrates rich in protein, and leguminous liay of some kind. Hence, not only more manure, but a better quality.

(12) The man who feeds concentrates and leguminous hays with silage is apt to try to grow legumes in the rotation. Hence, a better and more productive soil.

(13) Silage is a good feed for the general farmer.

(14) Silage is a good feed for dairy cows.

(15) Beef can be produced more economically when silage forms a part of the ration.

(16) Silage is a good feed for calves and stocker cattle.

(17) Silage is a good feed for breeding cattle.

(18) Silage is a good feed for fattening lambs.

(19) Silage is a good feed as a part ration for brood ewes if fed intelligently.

(20) Silage can be fed successfully as a part ration to mules.

(21) Silage can be fed successfully as a part ration for horses.

(22) Silage may be fed as a conditioner to swine in general, and as a part ration to old brood sows.

(23) Silage mixed with wheat and potatoes, equal parts, and boiled in water makes a good ration for poultry.

(24) Silage takes up less room in storage than either hay or corn fodder.

As to the kind of crops which can be preserved in the silo to advantage, it has been stated that anything which does not have a hollow stem will make good silage. This statement has a reasonable measure of truth. The reason that crops with hollow stems have been excluded is, that it is impossible to get the air pressed out of the stems, and on account of the presence of this air, decomposition is sure to take place.

The fact remains, however, that corn is pre-eminently the crop for the silo. As stated by Prof. C. H. Eckles, of the Missouri Experiment Station, and borne out by the statements of many other authorities, the total yield of nutrients per acre with this crop is greater than ordinarily secured from any other. It has the further advantage of packing well to exclude the air, and contains the proper amount of sugar to form acids needed to preserve without becoming sour.

An acre of corn as silage requires much less room for storage than an acre of corn harvested in any other way. When the harvesting is done the work is mainly over. The field is left clear for any fall sowing. Drilled corn yielding 75 bushels to the acre, when cut and shocked, eleven shocks to the acre, covers about 3 per cent of the area of the field. The shocks remain in the way of the next crop. Before the corn is husked out, bad, rainy, snowy weather often comes. The stalks,

Two of the Four Silos on the Dairy Farm of Thomas A. Edison, at Stewartsville, N. J.

blades and shuck become so damaged from the weather that they are not worth much as a feed, even if they were always fed in a dry, clean place where stock could not tramp them into the ground in wet, muddy weather. Tlie process of husking, throwing the corn on the ground, pitching it into a wagon and out again, and then out of the crib into the same wagon before it can be fed, is not only an expensive one, making the farm labor problem still harder to solve, but it is a wasteful one. Much corn damages from the weather.

from rats and mice and from shelling in handling so many times.

It costs on an average about 12^ cents to put corn into the shock and about 121^ cents to shuck it out. The stover (stalk without the ear), sells on the average for about 12% cents a shock. This is an expensive operation, even when it is the last resort, but on some farms it is a common practice.

However, when a man has no silo in which to harvest com and his crop rotation is such that corn is to be followed by wheat, or some other fall sowing, about the only thing he can do is to cut the corn and put it into the shock. This is especially true if a man is a grain farmer and cannot forage the corn off.

Again it may be stated that while silage can be fed to practically all farm animals to good advantage, it is pre-eminently the ideal ration for cattle, and especially the dairy eow. It thus forms an important link in connecting up one of our largest farm crops with the wide-spread and important industry of cattle raising and dairying.

The digestive organs of animals that chew the cud are so formed as to require comparatively juicy and bulky food. The cow cannot, therefore, thrive on exclusively dry food so well as can the horse. The nearest an ideal food that can be obtained for the dairy cow is good pasture; but for more than six months in the year green pasture is not available in large sections of this country. The best substitutes to use during this period are corn silage and such roots as mangels and turnips. Corn yields an average of twice as much dry matter per acre as do root crops, and, since the latter require much more labor, which in this country is relatively expensive, silage is far more economical.

The dairy cow has been likened unto a factory — a factory for the production of milk and butter. She eats her feed, converts it into blood and from the blood Avhich passes through the mammary gland or udder, she extracts the milk. The output of this factory, like that of any other factory, depends much upon the amount and quality of raw material consumed. No cow can produce a large quantity of milk and butter unless she has the capacity and consumes a large quantity of good feed. Since it is impossible to feed fat into milk or change the average per cent of butter fat in a cow's milk by the kind, amount or quality of feed, the thing for us to do is to feed her in such a way as to enable her to produce the maximum amount of milk. From more milk we can get more butter fat.

In order to get a cow to consume large quantities of feed, the feed must be good and palatable. Palatableness means much. Every feeder of live stock of any kind recognizes the importance of keeping the appetites of animals good.

During the process of fermentation of silage in the silo, the corn plant is rendered more digestible and more palatable than dry shock corn, and a flavor very acceptable to dairy cows is produced. After cows have been fed silage, they will stretch out their backs and turn their heads in the direction of the feeder the minute he starts toward them Avith a box of silage. So well do cows relish silage, they will eat more of it than they do of dry fodder or even of green corn. This is a point in favor of silage, because every cow must eat so much feed for the daily maintenance of her body. After this maintenance requirement is met, all excess food can be used for the production of milk and butter. However, some cows do not make use of this excess food in this way. They use it for surplus fat and flesh, thereby gaining in weight. The chief difference between dairy cows is shown in the difference in the disposition that they make of their food over and above that required for maintenance. Now, if every cow would absolutely refuse to produce a drop of milk until after her daily body maintenance requirements were met, some of us would learn a little faster how to feed for milk production. But not every, or even any cow, makes this demand. There are three classes of cows when both cows and the feed they are given are considered :

Class 1. Cows that receive more than a maintenance ration and use the excess for the production of milk and butter.

Class 2. Cows that receive more than a maintenance ration and use the excess for the production of surplus flesh and fat, storing it away on their bodies, growing heavier every day.

Class 3. Cows that receive less than a maintenance ration and have to draw upon the food nutrients already stored on their bodies in order to keep up a flow of milk, thus growing thinner and thinner in flesh every day.

This third or last named class is seldom found in the herd of the man who feeds silage. He feeds as a rule an abundance of palatable, succulent silage in combination Avith other feeds richer in protein content. The protein in the ration goes to make bone, muscle and the curd in the milk.

Silage is a roughage. RuDr'iants require a greater per cent of roughage in the rai )n than do other classes of animals. Corn silage comes the nearest to baving all of the properties of good green grass of any of the feeds we have. We can have it in the winter time, too, when grass is gone and other feeds are dry. We can have it in the summer time when the grass is short in dry periods of drought. Silage, above all other feeds, enables tlie dairyman to maintain almost unbroken summer conditions, conditions under which the maximum amount of milk and butter is produced.

A feed containing a large amount of water in the form of natural plant juices is not only more easily digested, but is also more palatable and, besides, serves the useful purpose of keeping the whole system of the animal in good condition. A silage-fed animal is rarely troubled with constipation or other digestive disturbances, the coat is noticeably sleek and soft, and the skin is soft and pliable.

No rough feed is more palatable than good corn silage. Sometimes, however, a cow will not eat silage readily until she has lacquired a taste for it; this may require several days. But silage is not peculiar in this respect, for it has been observed that range horses or cattle shipped into the corn belt refuse corn the first time it is offered to them. The quality of palatability is of great importance, as it induces a large consumption and stimulates the secretion of digestive juices.

The advantage of silage in the dairy industry was at one time put into a forcible statement by W. B. Barney, state dairy commissioner of Iowa. Among other things he said:

The dairy cow is the most economical producer of human food on the farm if fed and cared for in an intelligent manner. The milk of a cow that produces 10,000 pounds yearly contains 8,710 pounds of water,

290 pounds of fat, 485 pounds of sugar, 340 pounds of protein and 75 pounds of ash. Therefore, it is evident that the cow must consume large quantities of succulent feed to produce milk economically. The grass in summer provides her with such feed, but if the farmer is without a silo his cows are deprived of succulent feed for winter use. No man keeping six or more cows can afford to be Avithout a silo, regardless of its first cost.

Today the silo is no longer an experiment, and practically all the leading dairymen of the country are using them. Some seven or eight thousand new silos have been built in Iowa alone during the past year, which is sufficient evidence that they are a success. We are not suff'ering today in the rural districts for the want of finding new things so much as we are for the simple application of the things we already know. Practically every farmer admits that the silo is a good thing, but he puts off until tomorrow what he should do today, and the waste of crop continues from year to year. In the corn belt where stalks are allowed to stand in the field, 40 per cent of the crop is wasted. It has been estimated that an acre of corn put up in a silo has a value of $45, while the same standing in the field and husked has a value of $27. Thus it can be seen that the silo nearly doubles the value of the corn crop.

In feeding silage with alfalfa or clover hay we have practically a balanced ration all raised on the farm. Experiments have been conducted at the Kansas and other stations which show that the grain ration can be cut down one-half the usual amount where alfalfa or clover hay and silage are fed. Silage always plays a prominent part in the economical ration of most farm animals, and may the day be not far distant when the silo will be as common a sight on the Iowa farm as the corn crib is today.

In the Central West corn is hailed as the king of all cereals, forming the backbone of the rations of the majority of our farm animals. By placing corn in the silo the stalk as well as the ear is preserved, thus making the whole corn plant available for feeding purposes. Practically 40 per cent of the feeding value of the corn plant lies in the stalk, leaves and husks, the remainder in the ear. Therefore, if only the ears are gathered, much of the remaining 40 per cent of the crop remains in the field to bother the farmer in preparing his seedbed for the following year. As corn should be cut for the silo before the lower leaves are lost there is practically no waste. About twice the amount of dry matter can be stored in the form of silage as corn fodder. A cubic foot of hay in the mow contains about 4.3 pounds of dry matter, while a cubic foot of silage contains 8.9 pounds of dry matter. A cubic foot of space in the silo is, therefore, worth more than twice an equal space in the mow.

The digestive organs of animals that chew their cud are so formed as to require comparatively juicy and bulky feeds. The cow cannot thrive on dry feed as well as the horse. The ideal food for the dairy cow is green pasture, but for a number of months during the year she is deprived of this feed. The best substitutions for green pasture are root crops and corn silage. As silage yields twice as much dry matter per acre as roots and does not require as much labor, silage is by far the more economical wherever corn can be raised. Silage has a laxative effect upon the animal and aids in maintaining a healthy and vigorous condition.

The population of the United States is doubling every thirty years, which means that the farms will gradually become smaller and that more feed must be produced per acre. The high price of land also demands that more intensive methods must be used to obtain a dividend in proportion to the value of the soil. Practice tells us that one acre of corn placed in the silo will yield enough feed to supply a milk cow 40 pounds of silage for 500 days or 4 cows 125 days.

Another important factor is the reduction in storage space of silage compared to that required for hay.

One ton of clover hay occupies 400 cubic feet, while 8 tons of silage can be placed in the same space. The clover hay contains 886 pounds of digestible nutrients, while the silage contains 2,064 pounds. Thus the corn silage occupying the same space as the clover hay contains two and a half times the digestible nutrients.

Silage as a milk producer compares verj favorably with the other more concentrated and more expensive feeds. Being a very succulent and palatable feed, it can be very aptly termed the great substitute for pasture in the corn belt. We all look forward to the increased milk flow when the cows lare turned to pasture in the spring after having received nothing but dry feed for six months. The milk cow is a sensitive animal at hard work and should be nurtured on the best feed possible. Silage makes possible a succulent feed for winter use, spurring the appetite of the cow and causing her to relish her feed in winter as well as summer.

Several years ago at the Ohio Experiment Station the substitution of silage for grain in the ration proved very successful. Silage was used to take the place of over half the grain ration and proved to be much cheaper. The silage ration produced milk for 68 cents per 100 pounds and butter fat at the rate of 13 cents per pound. The grain ration produced milk at $1.05 per 100 pounds and butter fat for 22 cents per pound. This made the profit from, the silage ration $5.86 per month, and of the grain ration $2.46 per month.

There is an occasional suggestion that milk from silage fed cows has a disagreeable flavor. In order to determine what foundation, if any, there was for this belief, a series of experiments was sometime ago undertaken by the Agricultural Experimental Station of the University of Illinois.

For the purpose of these experiments, the University dairy herd was divided into two lots, one of which was fed 40 pounds of corn silage per cow per day, together with a small amount of clover hay and grain. The feed for the other lot consisted entirely of clover hay and grain. The milk from both the lots was cared for in exactly the same manner and was standardized to 4 per cent of butter fat in order that there might be no difference in the flavor of the two lots of milk on account of the variation in this respect.

The people whose tastes were consulted with regard to the milk were divided into three classes : ladies, men of the faculty, and students.

In one case the silage had been fed one hour before milking. Of the 29 ladies who sampled this milk, 10 preferred the silage milk, 14 the non-silage, and 5 had no choice. Of the men of the faculty, 27 preferred the silage milk, 20 the non-silage, and 7 had no choice. Of the students, 20 preferred the silage milk, 4 non-silage, and 4 had no choice.

A preference for silage milk was indicated by 51 per cent of the 111 tests made when silage was fed one hour before milking. When silage was fed at time of milking, 71 per cent preferred silage milk, and when fed after milking 51 per cent reported the same preference. Of the total tests, amounting to 372 persons, 223 preferred silage milk, 109 non-silage milk and 40 had no choice.

In making an investigation of the entire silo question, The Tiventieth Century Farmer, of Omaha, says that it found one man who, although having three silos on his place, claimed that silage was too expensive a fped for profitable use, and that he would not recommend other farmers to erect silos. He told the investigator that alfalfa was a much better and cheaper feed and he believed better results could be obtained by feeding more alfalfa and less silage. He was discovered, however, plowing up an alfalfa patch, putting in some com, and not feeding any new alfalfa that season. This resulted in an investigation, which seemed to show that the man's statements were prompted by selfish motives, rather than by his real feeling in the ciase. It was found that he had bought up during the winter, from his neighbors who did not have silos, and were thus compelled to sell, a lot of calves and young cattle, feeding them on the silage he had stored in his silos and making a very nice profit on the deal. If his neighbors were encouraged to build silos the possibility of his again taking advantage of their unfortunate circumstance would be very slight indeed.

One line of investigation followed by The Twentieth Century Farmer was to find out whether or not a much larger percentage of cattle could be maintained on the farms of the country by the more extended use of the silo and the feeding of silage year after year. This question was therefore asked of numerous farmers of from one to seven or eight years' experience in feeding silage, what percentage more of cattle could be kept profitably on their farms if they had sufficient silo room in which they could be sure to have silage to supplement the pastures in dry periods, and also to have plenty of this feed for winter time. While none of them had definite figures they could give, they all had some ideas based on their feeding experience. The answers to these questions from probably 50 different silo users have been that they could keep from 50 to 100 per cent more cattle by the use of the silo than they could without.

Silage stands first in rank of all the roughages for finishing cattle, says T. E. Woodward, of the U. S. Department of Agriculture. Formerly, during the era of cheap corn and other concentrates, little attention was given to the roughage, as it was usiially considered merely a ''filler" and of very little economic value in feeding. No especial care was taken in selecting any particular kind, nor was the quality of it seriously considered. As the prices of the concentrated feedstuffs advanced, the feeder looked about for methods of cheapening the cost of producing beef, and soon found this could be accomplished by using judgment in selecting his roughage with respect to the grain fed. This has continued until at the present time the roughage receives as much attention as the concentrated feed, and has been made to take the place of a large amount of the latter. The feeding of silage came into general use with the advent of expensive grain and is becoming more popular each year. With the present prices of feedstuffs, there is hardly a ration used for feeding cattle which cannot be cheapened by the use of this succulent feed. By combining it with other feeds, the efficiency of the ration is increased to such an extent that the amount of the daily gains is invariably greater and the cost of producing a pound of gain is lessened. The heaviest daily gains are usually made during the first stage of the feeding period, and silage can then be used to advantage in large quantities with a small amount of grain, but as the feeding progresses the amount of silage should be lessened and the grain increased. In some places the price of hay and stover is so high that the greater the proportion of silage used in the ration the more profitable is the feeding.

Silage is a quick finishing roughage in that it produces large daily gains and produces a glossy coat and a soft, pliable skin. Moreover, it can be used to advantage at times for carrying cattle for a longer time so as to pass over a period of depression in the market, or to carry the cattle along in thrifty condition so they can be finished at a later period.

For many years the belief was general that cattle which received silage as a major portion of the roughage would have to be kept in warm barns and not exposed to the cold. While they do need protection from the cold winds 'and rains and need a dry place to lie down, it has been clearly demonstrated that warm barns are not only unnecessary, but that fattened cattle make both larger and cheaper gains when fed in the open sheds than when confined in barns.

Silage can be profitably used to supplement the pastures for steers during a time of drought, when they are being finished for market.

The general impression that choice or prime carcasses cannot be made by the use of succulent feed is equally untrue, as the silage-fed cattle usually make more desirable carcasses than cattle fed a similar ration except that silage was replaced by one of the coarse fodders. There is no appreciable difference in the percentage of marketable meat that steers will dress out which have been finished on a silage ration and .a dry ration. The meat seems equally bright and the fat as well intermixed with the lean.