Summer management tips for compost dairy barns

Vince Crary, Extension Educator, University of Minnesota

Dairy producers with compost dairy barns tend to all do things a bit different during the summer months. One thing all producers should do the same is remember how difficult it was to get the sawdust you needed to make your barn work during this last winter. Work with your sawdust supplier and stockpile sawdust during the warmer months of the year.

A number of compost dairy barn users have told us you do not have to worry about the sawdust being rained on; you only need to make provisions so the wind does not blow your sawdust. Working with your sawdust supplier through the summer months will provide them with a place to take their product and will provide you a more consistent supply for next winter.

You may also find reduced prices during the warmer months. Fuel costs may impact the price you pay for sawdust this summer. However, the benefit is that you will have a supply ready for next winter, which will help you better manage your compost dairy barn during the winter months.

A number of dairy producers have an outside lot cows can choose to use versus the compost dairy barn. Producers say cows prefer to be outside on a cool overcast day and in the barn during hot sunny days. A number of dairy producers with compost dairy barns have put in fans for the hot sunny days when the cows choose to use the barns. If you do not have fans, cows tend to stand in the area of the barn that has air movement instead of spreading out through the whole barn. This well-ventilated area will get more urine and manure and needs to be stirred well.

Producers will often stir the compost area in different directions to insure a good mix of the concentrated areas of urine and manure from cows standing in a given area to take advantage of air movement. For example, they may stir the pack lengthwise and crosswise to get the concentrated urine and manure well mixed.

Do fans pay? This is a question each producer needs to think about. See how your cows are acting on hot sunny days. Do your cows remain spread out in the barn or are they crowding in one well-ventilated area of the barn?

You also need to think about the many different types of fans available that can be put into a compost dairy barn. The big ceiling fans used in churches are being used by some producers. Other dairy producers have used the big box-type fans that blow across the compost area. When considering an overhead fan, make sure you have adequate overhead room so you can stir your compost area without hitting the fans with stirring equipment. Look at the costs, the benefits and what the cows are telling you they need to make a decision on what you want for fans in your compost dairy barn. PD

—From University of Minnesota Compost Dairy Barn Newsletter, May 2006