Set trigger points and plan to meet your targets
Trigger points spark action well before critical feed shortages. For example, if it hasn’t rained by a certain date or pasture availability drops below your targets, you might change your weaning time, sell stock, begin supplementary feeding with stored forage, purchase grain for ewes and weaners, or plan to use nitrogen and rotational grazing in order to boost pasture growth leading up to lambing.
Setting targets is one thing. Putting a plan in place to meet those targets for animals and pasture is another, but it is achievable. This planning requires:
- Identification of a pasture quality and quantity target on a particular date (a trigger point). An example might be: 1,500 kg green DM/ha at 70% digestibility to wean lambs onto at 12 weeks of age on 5 November.
- A grazing plan to build feed reserves in the identified paddock and ensure the required pasture will be available when needed. Based on the example above, this may include:
- Identify the weaning paddocks at joining.
- The grazing plan will allow autumn grazing of the weaning paddocks to manage weeds and encourage clover growth; a light grazing over winter, perhaps by cattle or wethers to reduce worm larvae; then a rest from mid-spring to allow pasture to accumulate.
- Given the pasture mass at the end of winter, you can calculate how much pasture will accumulate each month towards the target of 1,500 kg green DM/ha by 5 November.
- 400 kg DM/ha at the end of winter + 30 days in September at 30 kg DM/ha/day + 31 days in October at 45 kg DM/ha/day = 2,695 kg DM/ha by the end of October.
- 2,695 kg DM/ha is well above the November 5 target for the weaning paddocks. You may not need to lock up the paddock until the start of October (500 kg DM/ha at the end of winter + 31 days at 45 kg DM/ha/day = 1,895 kg DM/ha by 5 November).
- Plan paddock allocations using the benchmarks in table 8.1 to check that animal demand can be met by pasture supply.
- Use feed budgeting for short- and long-term planning.
- Take appropriate action once you have reviewed the situation at your trigger point. For example:
- If stock meet your condition score targets and the feed budget predicts you will have enough feed: do nothing but continue to monitor pasture supply.
- If stock meet your condition score targets but the feed budget predicts that pasture supply will not meet their nutritional demands in three months’ time, your options include:
- Grow more pasture: put on nitrogen to boost pasture supply; assess availability of other paddocks for grazing.
- Consider the option of grazing crops.
- Reduce stocking rate: re-allocate stock to another paddock, draft off dry ewes, seek agistment for your sheep elsewhere, or sell some stock.
- If stock are below your condition score targets and you will have less than your target feed in three months’ time, your options include:
- Feed supplements now and grow more pasture.
- Reduce stocking rates.
- Accept a lower production level and potential damage to the pasture or soil base.
- If stock meet target condition score and the feed budget predicts you will have a feed surplus in three months’ time:
- Can you agist or trade extra stock now?
- Can you conserve fodder for later?