Silage Production and Feeding – Part I

Silage is a popular term often used among forage and livestock producers and related agencies. What is silage? Silage can be defined as plant materials that have undergone fermentation in a silo. Then what is silo? Silos are storage structures used to preserve green, moist forage.

Forage crop harvesting, preservation and feeding as silage is a common practice throughout the U.S. and in many countries in the world. Preserving forage and using it as silage is very convenient, especially in terms of storage and economics. Silage is a very economical source of feed in dairy industry, and it is increasingly used in beef backgrounding and finishing programs.

Advantages and disadvantages

There are many advantages in using silage. Some of the advantages include reduced field and harvest losses compared to hay and a large number of crops that can be used to produce silage.

There are also several available options for mechanization of harvesting, storage and feeding and silage, and producers see a reduced loss of silage due to weather damage during harvesting than with other feedstuffs. It can be stored for long time under proper conditions with minimum losses of nutrients, and silage can be used in many programs of livestock feeding.

From these advantages, many livestock producers can benefit by incorporating silage into their operation systems.

However, there are some disadvantages, as well, in using silage. For example, silage is bulky to handle and store; it requires specialized equipment and structures to harvest, store and feed; losses could be substantial, if not properly ensiled or stored; when not used in the farm, silage is not rapidly marketable; and most importantly, to avoid spoilage, silage must be fed quickly after removal from the silo.

Silage crops

There are many forage crops that can be used for silage.

However, the decision of what crop to utilize should be made based on type of livestock to be fed, expected yields of the crop, availability of the machinery to be used and the type of soil and site of planting for the silage crops.

These factors are important when making silage, as most of the aboveground parts of the crops are removed. As a result, removal of nutrients from soils is much higher in silage crops than, for example, when the same crops are harvested for grain.

It is advisable to make an adjustment in fertility programs to ensure adequate plant nutrients for the following crops.

Crops that are extensively used for silage include corn, grain sorghum and small grains. Other forage crops include alfalfa, forage sorghum, grass-legume mixtures and various high yielding grasses. These other crops require wilting for reducing moisture content to ensure proper ensiling.

Corn is the best among the silage crops and ranks number one as a silage crop. Corn silage has high energy and produces high animal performance.

Quality and yields vary among silage crops and depend on duration of crop growth and time or frequency of harvesting. The dry matter yields can range from two tons per acre, as in oats, to six tons or more, as is seen in corn. Crude protein, on a dry matter basis, can range from eight percent in corn to 18 percent as is seen with alfalfa.

Discussion on the ensiling process, silos, factors affecting silage quality and feeding silage will be in future Extension columns. Keep and eye out for these columns in the Roundup.

Anowar Islam is an associate professor and the University of Wyoming Extension forage specialist in the Department of Plant Sciences in the College of Agriculture and Natural Resources. He can be reached at 307-766-4151 or mislam@uwyo.edu.