Organic dairy growth prompts field conversion

By D. Bruce Bosley

Extension Agent/Cropping Systems

Colorado State University Cooperative Extension

Many ag producers are converting their irrigated fields from growing corn to producing irrigated pastures for grazing livestock. These can include annual forages that are planted every year (or twice a year in some cases), or perennial forages that can be planted only once for a few years to as many as several decades. I've recently received a lot of interest in planting pastures for organic dairy grazing.

This new interest in organic dairy production comes in part for the growing organic industry and also from proposed changes in the organic dairy standards which, if enacted, will require dairy herds to get a minimum of 30 percent of their forage nutrition from grazing pastures. In the United States grass-based organic dairy farms are fairly common in the northern mid-west and northeast. Grass pastured dairies are rare in the Western United States where the milk cows are housed in confining sheds and pens. The trend in western dairy production is to increase the herd size in farms from tens and a few hundred milk cows to thousands per farm operation.

Grass-based dairies use skilled management and controlled rotational grazing. Managers offer dairy quality forages for the entire grazing season. It is a challenge to supplement this forage diet for optimal milk production and profitability. Certain breeds or individual cows are more adapted to a seasonal grass-based system. Therefore, animals must be selected for the farm's grazing system. Grazers report improved health when cows are on pasture most of the year. Special equipment for fencing and water systems has been developed and is increasingly available.

Grass-based dairies differ from confinement dairies because cows harvest their own feed, reducing the need for costly supplemental feed and other purchased supplies. However, they require considerably more management skill. Although the production of high quality milk must remain a central goal, this system demands that you also manage the forage as an important crop in itself. It can be useful to think of the milk as a means of marketing the forage. Monitoring forage resources, proper feed supplementation, adjusting stocking rates, and controlling grazing duration will require the manager's attention in order to maximize milk production using forage resources.

A key decision is to choose forages that give high production over the entire milking season. In the earlier days of rotational grazing, high pasture diversity and lower fertilizer inputs were valued. Now dairy grazers with high utilization rates can justify using higher N levels. They are also adding special-use pastures of fewer species in order to extend the grazing season. Using summer and winter annuals through no-till establishment can be economically viable in a dairy grazing program.

CSU Extension personnel can help in choosing forages that are productive.

Please contact me, Bruce Bosley with your cropping systems questions or natural resources questions: 970-522-3200 ext: 285. Thank you!

Date: 2/21/06