SILOS

The earliest reference to a silo appeared in The Aurora in the July 1883 issue:

One of the most practical and important experiments prosecuted by Prof. Knapp is now subjected to the test, and if successful will prove of great advantage to the farming public. A silo has been built in one corner of the barn 16.66 x 11.8 feet, and about 20 feet deep. This was made with air tight sides, and on the 16th and 17th inst. was filled with clover and other grasses from the college lawns and farm. The grass was raked as soon as cut and hauled directly to the silo where it was spread and packed as thoroughly as possible. Twenty-one and one-fifth tons of grass was put in the pit and a loose floor of two inch plank fitted over it, a loose cross floor was put in and on this boxes of sand were placed to the amount of about five tons. The grass settled under this weight in twentyfour hours from fifteen to ten feet, and the Professor expects it to settle five feet more, making “canned grass” with a weight of about 40 pounds per cubic foot.

Ensilage has been in use in the east for several years and we think will be a success here, and if so, the Professor will “can” large quantities of corn and grass another year. We shall watch with interest the outcome of the experiment.

In the Biennial Report for 1896-97 it is stated, “We are seriously in need of a commodious horse barn… It is desirable to build, in connection with it, a silo with a capacity of 400 tons in order that we may have proper facilities for feeding in accord with this important method of preserving foods.”

The September 23, 1905, issue of the ISC Student reported that “the brick silo located on the northwest corner of the experiment station barn was filled with corn from the fields north of the Chicago & Northwestern tracks.”

About a year later it was recorded that “The Experiment Station is constructing a new silo. It is of hollow building brick and is called the Iowa Silo. It will have several advantages: a well insulated wall; durability; and reasonable cost.”¹

In 1912 a new development, a concrete silo, was undertaken. That is described in the following account from the the October 5, issue of the ISC Student:

“As solid as the rock of Gibralter,” was the claim made yesterday by Mr. A.M. Lawrence for the big forty foot reinforced concrete silo he is building for the college at the northeast corner of the cattle barns. “This type of silo is absolutely indestructible by wind or fire; it will never cost a cent for repairs, is absolutely vermin proof, and will protect the ensilage as well or better than any other type of silo against spoilage from air or moisture” said he.

The new silo is a present to the farm department of the college. The Universal Portland Cement Company of Chicago has sent Mr. Lawrence here to Superintend the erection of the silo, and is furnishing all the cement used in its construction without charge to the college. The steel forms for the concrete are furnished by the Enterprise Monolithic Silo Construction Company of Chicago, and the metal roof is supplied by the Hyrib Roofing Company. The concrete mixer is loaned by the Cement Tile and Machinery Company of Waterloo. So apart from the labor, and the gravel used, this silo is a gift to the college of a most practical kind.

The silo under construction has a diameter of fourteen feet, and will be forty feet high. Its capacity of ensilage will be about one hundred forty tons. Six inch solid concrete walls from a one part cement to a five part bank run gravel sand mixture, are reinforced at the bottom by steel triangle mesh two layers, one of No. 4 and one of No. 6 mesh being placed in the first twenty feet, and a single No. 6 layer reinforcing the remaining twenty feet. The silo will have a continuous door and a chute, the door frame being entirely of concrete construction. The metal roof is also coated with cement.

The Universal Portland Cement company is not in the silo construction business, but is making a demonstration here in this silo of the advantages of concrete construction in silo building. “Engineers the world over all agree that the best building material known to man is reinforced concrete,” said Mr. Lawrence. “It is true that the initial cost of a concrete silo is somewhat greater than that of a wooden silo of equal capacity, and in some cases the tile block silo can be erected more cheaply, but when the farmer takes into consideration the stability and permanence of his concrete silo, its unquestioned imperveriousness to air and moisture, and the fact that once properly built he will never be at additional expense for repairs, he will conclude that the concrete silo is the cheapest in the long run.”

“Concrete silos have been built in many of the eastern states for some time past, and are now being rapidly introduced in the middle west. The price of concrete construction ranges from ninety cents to four dollars per ton capacity, depending upon local conditions, labor, accessibility to gravel, and etc. Any farmer who has had some experience in concrete construction can put up his own silo, although we advise the farmers to secure the services of a competent contractor whenever possible.”

Completion of that silo was reported on October 29.

When the new Cattle Barn was built in 1925 hollow tile silos were included at the northeast and northwest corners of the barn. They were 16 feet in diameter and 45 feet high.²

A short review of the silos appeared in the October 18, 1927 issue of the Iowa State Student:

The first block silo to be built in the state of Iowa was constructed on the Iowa State farm and now stands north of the old cattle barns, where it was erected in 1907 by the Agricultural Engineering Department.

When this silo was contemplated as an experiment, most people considered the project foolish and when the contract for the properly shaped blocks was let, taxpayers appeared impressed by the fact that their money was being spent foolishly.

The silo has been in use up until this year, when the new barns were completed and the stock moved to the new location.

Another silo, partially constructed for experimental work, and located north of Old Agricultural Hall, was one of the earlier silos. It consisted of only six compartments and was used as a test for water-proofing compounds on its walls. It was also used to show farmers the methods of constructing a permanent, hollow clay block silo.