On-off grazing is a management technique to minimize damage while grazing wet pastures. It is an alternative to using a sacrifice paddock.
Livestock do the least amount of pugging damage to a field when they are actively grazing. It is other activities, such as visiting the water trough or mineral source, lying down, or socializing that cause more damage. Research in Ireland has shown that cattle with unrestricted access to pasture spent only 37% of their time grazing. The researchers studied how restricting the amount of time cattle spend on pastures affected both pasture damage and dry matter intakes. When cows were allowed to graze 24 hours/day, pugging damage resulted in 20% lower pasture yields than when grazing was time limited. The on-off grazing technique is a result of this work.
How to On-off Graze
Cows can eat their entire daily forage dry matter intake during two 3-hour grazing periods per day. When managed this way, the researchers found the cows spent 98% of their time on pasture grazing, which reduced damage.
To on-off graze:
- Use temporary electric fence to allocate just enough grass to meet half the herd’s daily intake needs.
- Turn out the herd for 3 hours of grazing in the morning. When time is up, bring the cattle back into a barn or dry lot.
- Move the electric fence to allocate enough grass for the remainder of the herd’s daily forage needs.
- Turn the herd out for 3 hours of grazing in the afternoon or evening. When time is up, bring the cattle back into a barn or dry lot.
It generally takes about 2 days of on-off grazing for livestock to get the hang of their new wet weather feeding (grazing) routine.
Top tips for on-off grazing:
- Turn livestock out hungry! While animals with high nutritional requirements (dairy, grass-finishing, and young stock) may need a little stored forage overnight, the goal is for animals to put their heads down and graze right away.
- Bring the herd back in when animals start to lie down.
- Use the driest paddocks for on-off grazing.
- Consider starting to graze furthest from the barn or dry lot and working your way towards it so animals are not walking on grazed areas that have less protection from pugging.
Sometimes temporary alleys must also be created with portable fencing to enable on-off grazing. These will suffer pugging damage as the herd moves between the pasture and the barn or dry lot, but the alley represents a much smaller area of damage than allowing the herd access to the whole pasture. More details on assessing and repairing pugging damage can be found here.
A video explanation of on-off grazing can be found here.
When to On-off Graze
On-off grazing is an option any time pasture soils are saturated and prone to pugging damage. It is of most benefit when:
- Maintaining high quality forage is important (i.e., dairy, grass finishing, or young animals).
- Stored forage inventories are tight. Unlike a sacrifice paddock, on-off grazing does not rely on stored forage to feed livestock.
- Extending the grazing season to keep costs down is a priority.
While on-off grazing is an effective way to protect and utilize wet pastures, the labour involved makes it best suited to short-term use rather than as a normal grazing system.
Kennedy, E., O’Donovan, M., Delaby, L., and Boland, T. 2012. Strategies to increase the length of the grazing season for spring and autumn calving cows. Teagasc Technology Updates. Available: https://www.teagasc.ie/media/website/publications/2011/Extending-the-Grazing-Season_5798.pdf