Ensilage
Aiton's Encyclopedia (1910)
in agriculture, fodder preserved in a green state. In the ordinary use of the word, ensilage is canned corn fodder. Any forage plant may be packed for ensilage, but green corn, not quite arrived at maturity, is preferred. A silo or pit may be built of any air-tight material. Wood is the material most generally used. Of late concrete is finding favor. A common wooden silo is of circular form, like a well. The deeper the silo the better. The fodder is chopped or shredded, and is filled in from the top. Tramping, especially around the edges, facilitates settling. A mass of fodder packed in this way is protected from the bacteria of decay just as canned vegetables are protected by the tin of the can. The ensilage cures in its own juice and affords green, succulent feed when pastures are bare. The silo is to the fodder field and the barn what the tin can is to the vegetable garden and the pantry. Cattle are as fond of good ensilage as people are of canned vegetables. Ensilage has especial value as food for milk cows. Like green pasture, it increases the flow of milk. Some writers are of opinion that silos, in the form of pits, were known to the ancient Persians and Romans. Several of the European nations have understood the value of pits for green fodder. The scientific silo was first worked out in France. The first American silo is thought to have been built in Maryland in 1876.
What Has Changed in the Last Century
Aiton's 1910 account had the mechanism backwards: it said packed fodder "is protected from the bacteria of decay just as canned vegetables are protected by the tin of the can." In fact silage keeps because bacteria do the work — lactic-acid bacteria fermenting the crop's sugars in the absence of air until the pH falls low enough to stop spoilage; A. I. Virtanen won the 1945 Nobel Prize in Chemistry partly for work on preserving fodder by acidifying it. The word has changed too: "ensilage" has largely given way to "silage", and the deep circular wooden silo Aiton described has been displaced on most farms by concrete bunkers, sealed plastic bags and individual round bales wrapped in film. What has not changed is the verdict on its value — maize and grass silage remain the backbone of dairy-cattle feeding across Europe and North America.
Written for this edition, 2026.