Extend autumn grass rotations
August saw both extremes in terms of grass growth. Some of it was excellent while more of it was very dry, resulting in poor grass growth rates.
Each individual farm has its own set of circumstances, but many dairy farms came into this month with one of two extremely different scenarios:
1. Average pasture cover had decreased and was substantially behind target.
2. Average pasture cover was on target but some paddocks had heavy covers of poor quality.
Recently, I took a group to visit two farms, which highlighted these two extremes in pasture cover. Farm A had a stocking rate of 3.5 cows/ha and an average cover of 570kg DM/ha. It was in a clear deficit, though pasture quality was excellent. Farm B had a stocking rate of 3.2 cows/ha and an average cover of 870kg DM/ha, though at least four paddocks were heavy with covers in excess of 2,000kg DM/ha prior to a big dip in the feed wedge to lower covers.
I imagine most farmers would rather be in the comfort of the situation of farm B. This obviously requires less immediate action and less supplementary feed. However, for farm B, there was still some debate to what needed to be done with regards to when and how much feed should be introduced, and how to achieve good post-grazing residual covers on the paddocks without sacrificing both cow condition score and milk yield.
One of the visiting farmers highlighted the extremes of the two situations and asked me which one would I prefer to manage. The answer was simple -- farm A. Why? Because the set of decisions that need to be taken in a feed deficit are clear and simple. For those of you that have a lower-than-desired pasture cover this autumn, there are three actions to take:
- Immediate action -- don't chance the recovery of a low pasture cover in the autumn.
- Extend rotation length. In early September move to 1/35 (35 days) or 1/40 (40 days) if in a large feed deficit.
- Reduce the demand for pasture (increase supplementary feeding or reduce numbers).
Autumn is a period characterised by the fall in pasture growth below pasture demand. Therefore when presented with a feed deficit, immediate and adequate action is required to limit the deficit becoming even larger.