Storing large round bales

Glenn Selk, Oklahoma State University Emeritus Extension Animal Scientist

The very dry spring (that most of Oklahoma has endured) points toward short hay production this summer and expensive hay feeding next winter.  As hay is being cut and put in large round bales, it is very important this year to reduce hay storage losses.   University of Tennessee animal scientists conducted a trial to compare different methods of storing large round bales of grass hay. The hay was cut and baled in June in Moore County, Tennessee. The bales were weighed at the time of harvest and storage. Then they were weighed again the following January at the time of winter feeding. The following table lists the type of storage and the resulting percentage hay loss.

Table 1. Losses of hay stored using six methods of storage  (Source: Dr. Clyde Lane, University of Tennessee Department of Animal Science)

Type of Storage

Percentage (%) of Hay Loss

On ground, no cover


On old tires, no cover


On ground, covered


On old  tires, covered


Net wrap on ground


In barn


Average spring, summer, and fall rainfall in Tennessee will generally be greater than that experienced in much of Oklahoma.  However the rankings in storage loss between the storage methods will be present in Oklahoma as well.

An Oklahoma State University fact sheet by Dr. Ray Huhnke summarizes differences in storage loss that can be expected in an Oklahoma ranch setting.  Source:  Oklahoma Cooperative Extension Fact Sheet BAE-1716 “Round Bale Hay Storage”.

Table 2. Percentage (%)  dry matter loss of round hay bales.


Storage Period

Storage Method

Up to 9 months

12 – 18 months





5 – 20

15 – 50


3 – 15

12 – 35





5 – 10

10 – 15


2 – 4

5 -10

Under roof

2 – 5

3 – 10

Enclosed barn

Less than 2

2 -5

Obviously, it would be ideal to store the hay inside, but that will not often be practical. The next best option is when the hay is stored on something that gets the hay off of the ground under a rain shedding cover.  

Posted in

Tagged keywords...