Drive-Thru Corn Crib

Drive-Thru Corn Crib, IBF Magazine

The Drive-Thru Corn Crib

By Duane Fenstermann

For more than 15 years the Iowa Barn Foundation (IBF) has highlighted the preservation of Iowa's barn history. The IBF became a national leader in this effort. Most Iowans knew the function and architectural features of the thousands of classic barns that facilitated Iowa's past agricultural economy. IBF's grant and Awards of Distinction program has helped to foster that common knowledge.

Unfortunately, the same cannot be said about modern present day Iowa barns made of metal roofs, pole shed framework, and total enclosure of livestock. A traveler on Iowa's interesting rural roads does not readily know if the building is for cows, pigs, chickens, turkeys, or what. There is more to confuse the Iowa traveler: enclosed cat fish farms are emerging. A retired public school building in northeast Iowa now contains shrimp growing tanks.

Recently a query came from an architect in Denver, Colorado. He had photographed an Iowa farm yard on one of his travels that contained a corn crib with a "copula." He wondered what the copula was for because the photograph included a barn with a copula and they looked very different.

Corn Crib
Figure 1: Corn crib with alley and a lean-to for small grains. Photo courtesy of Peter Harding.

His very appropriate question illuminated a number of issues of interest to IBF and the traveling public. Iowa farming methods, buildings, and technology has evolved so fast and pervasive that the general public no longer understands how the whole system works and what they are seeing in their visual horizons. Many traveling people have never even been on a farm yard, to say nothing about their understanding of the buildings and equipment. Some of us who have grown up on farms have the same learning curve. No one wants the evolution to return to a former agricultural era.

The question about the architectural profile of a corn crib complements a growing awareness emerging from the more recent spring and fall IBF self-guided tours of barns across Iowa that have received either an IBF preservation assistance grant or an award of distinction. Many people touring the barns have not grown up on farms. Many questions arise about how equipment works or why the barn was designed in a certain way. IBF is finding itself in the role of explanation and education – two worthy adjuncts of preservation.

With this background we can transition to a discussion about a particular type of corn crib. Figure 1 shows the photograph sent with the corn crib query. The structure on the ridge of the barn is a traditional barn cupola. Definitions recognize that a cupola is an upside down cup type structure placed on the ridge line of a building to function as a light source, a belfry, belvedere, or lantern, but seldom associated with Midwest barns. Iowans, however, know that the barn cupola is placed on the barn ridge line to provide ventilation for the haymow space to prevent a build up of internal temperature and spontaneous combustion of wet hay stored inside. The barn shown in Figure 1 has only one cupola, but many barns have more than one, using a formula that dictates the size of the opening needed for proper ventilation and the number of cupolas per linear feet of the ridge line. In the process of building the cupola carpenters often developed their own style of cupola design and trim, which resulted in a trademark or signature identifying that particular carpenter.

Corn Crib
Figure 2: Corn crib built by Arthur Fiet, Allamakee Co., in 1946, now owned by Larry Snitker, resided with metal. Photographed by Marlene Fenstermann on May 15, 2016.

The structure on the corn crib roof might loosely be called a corn crib cupola, but Iowa farmers would avoid confusion with barn cupolas. They call it the "elevator head house" or the "granary equipment loft" because they know its function and it was not for ventilation. However, Iowans would avoid the granary term because we know the corn crib as a "grainary." The corn crib was actually two corn cribs with a drive-thru alley between the two cribs. It was the storage house for ear corn and various small grains used in crop rotation farming.

Prior to the mid-1940s corn was picked by hand in the fields, using a husking peg strapped to the hand to quickly strip the corn husk off the ear of corn. It was then thrown into a wagon with an extended height on the far side equipped with a "bang board." When the wagon was full the farmer took it to the corn crib in the farm yard with a team of horses or an early primitive tractor. The corn crib had walls of horizontal boards with about an inch between each board. The slots allowed air drying of the ears of corn placed inside. During the hand-picked era the corn crib was a simple stand-alone building that often revealed ethnic heritage in its construction features, such is sides that were narrower at the bottom than at the top, or was a smaller storage area incorporated into the side of a barn or hog house, but those designs are not included in the scope of this article.

The corn crib structure was narrow to encourage the air drying. However, to get the ear corn into the crib the farmer had to shovel it by hand and throw it over the top horizontal board, which usually was higher than the wagon and up near the roof of the corn crib. It was hard work.

Then, as one row corn pickers were manufactured, after WWII with materials released from the war effort, the number of wagon loads of ear corn a farmer could produce in one day greatly exceeded his ability to unload the corn into a crib with a scoop shovel. His need for more corn storage space also increased. By building two corn cribs side by side, with an alley space in the center, wide enough to handle the corn wagon, the alley created an air tunnel effect that assisted in the drying process.

Corn Crib elevator
Figure 3: Vertical elevator metal shaft on the left. Metal buckets on the right traveling downward to the floor hopper to be filled with grain. Photo detail from the corn crib shown in Figure 2.

By the mid to late 1950s this alley space was used for another important development: the vertical elevator. This was an endless belt or chain with metal buckets or shelves that lifted the ear corn to the top of the corn crib and dumped it into a chute or trough that directed the corn into the storage areas. The elevator was anchored to one side of the alley. In the alley driveway, either below ground or hinged to the elevator side was a hopper into which the wagon load of corn was dumped. Figure 4 shows a hopper in the upright position to allow wagons through the alley. It was lowered behind the wagon.

Corn Crib
Figure 4: The grain hopper in the alley was either below ground level or lowered to the floor level after the corn wagon was in position. Aarik Deering. Photographed by Marlene Fenstermann May 15, 2016.

Thus, the mechanical house on the top of the corn crib housed the upper parts of the vertical elevator. If the farmer did not have the vertical elevator but had an adjustable elevator he would position the elevator across the roof and send the corn through one of the windows of the roof house. An example of this is shown in Figure 5.

Corn Crib
Figure 5: An external elevator inserted into an elevator head house. After the corn picking season was finished the elevator could be removed. The pile of corn cobs was produced by the out-of-view corn sheller. Photo courtesy of Denny Hurtz.

Corn Crib
Figure 6: This corn crib was built on a limestone basement with an earthen ramp on the other end. The Aarik Deering farm in Allamakee Co., IA. Photo May 15, 2016, by Marlene Fenstermann.

With the growing need to increase corn production and with the manufacturers ability to invent and improve current methods, by the late 1960s corn combines came into accepted farm use. The adoption of the corn combines totally changed corn production and support systems. Now the ears of corn were shelled from the cobs right in the field by the combine. The farmer no longer needed corn cribs to dry and store ear corn. The double corn crib with alley, the vertical elevator or the adjustable elevator, the traveling corn sheller man and equipment, wagon jacks, power take-off systems, and rat controls, all were now obsolete and not needed. The farmer now needed round steel bins with bottom duct work for air ventilation and unloading; and elevators that look like a round tube with an spiral auger inside.

Corn Crib
Figure 7: Corn Crib owned by John Rodecap, Winneshiek Co., IA. The round metal structure was not original to the corn crib. Photographed June 2, 2016, by Marlene Fenstermann.

Once a decision was made to write this article this author has been alert to find good examples of the double corn cribs with alley and a roof mechanical house. Unfortunately, few still exist in northeastern Iowa and southeastern Minnesota. My father-in-law built one in 1946 (Figure 2), but now we know the life cycle of the drive-thru type of corn crib was very limited, due to the quick acceptance of the combine and storage of shelled corn. The corn crib of Figure 2 is no longer used for its original purpose and other existing cribs are in much decay with no useful purpose. Others are just gone.

A wonderful example of adaptive use of a corn crib is a home in central Iowa. The owners moved the crib from a mile away, insulated it on the outside, converted the inside, allowing the boards and open studs to be seen, and converted it into a very comfortable home.


Persons desiring to explore the double corn crib with alley may wish to check out these sources:

This North Dakota State University web page has building plans (#5323) for a drive-thru granary to hold ear corn. Shows details for the top mechanical housing. See also plan #5325.

An article by E. A. Olson, titled "EC739 Corncrib Construction," from the University of Nebraska – Lincoln Extension, discusses many features, but note the many dimensional data presented.

This article by Dirk E. Maier, titled "Ear Corn Drying, Storage and Handling," October 25, 1996, Fact Sheet #29 from Purdue University, gives dimensional recommendations for drying of ear corn in ventilated cribs.

Worldcat lists 47 books about corn cribs. Your local public library probably can find them for you on inter-library loan.

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