Summer feed budget on a hill-country sheep unit
A 600 ha hill-country sheep and beef unit in southern Hawke's Bay carries 3,000 mixed-age Romney ewes and 700 ewe hoggets. It is 20 December, soil moisture is below wilting point to 30 cm, and the 10-day forecast is 30 °C with no rain. Pasture growth is 3 kg DM/ha/day. Average pasture cover is 950 kg DM/ha and falling. Ewes are 140 days pregnant, and 60% are carrying twins. Current demand is 1.5 kg DM/head/day for ewes and 1.0 kg DM/head/day for hoggets. The owner has 80 bales of balage (900 kg each, 85% DM) and can buy more at $320/bale. Lambs are due in 25 days. A neighbour offers $2.10/kg liveweight for store lambs at weaning. Options include selling 300 cull ewes now, feeding balage, applying 30 kg N/ha, or grazing a 30 ha spelled paddock with 2,000 kg DM/ha.
1. Prepare a feed budget to lambing and decide whether the current plan is safe.
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Demand: 3,000 ewes × 1.5 kg DM = 4,500 kg DM/day; 700 hoggets × 1.0 kg DM = 700 kg DM/day; total 5,200 kg DM/day. Supply: 600 ha × 3 kg DM/ha/day = 1,800 kg DM/day. The deficit is 3,400 kg DM/day. Over the 25 days to lambing the deficit is 85,000 kg DM.
Pasture cover is 950 kg DM/ha. To reach a minimum of 800 kg DM/ha at lambing, a sensible target for hill-country ewes with twins, the farm can release (950 − 800) × 600 = 90,000 kg DM. So the farm can just cover the deficit from cover, but it would arrive at lambing with no buffer and no ability to feed lactating ewes. That is not a safe plan.
The 80 bales supply 80 × 900 × 0.85 = 61,200 kg DM, which covers about 18 days of the deficit. Selling 300 cull ewes saves 300 × 1.5 = 450 kg DM/day, or 11,250 kg DM over 25 days. Combining culling and balage avoids dropping below 800 kg DM/ha and leaves some feed for lambing. The current plan is therefore not safe on its own.
2. Evaluate applying 30 kg N/ha now as a way to close the feed gap.
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Nitrogen is unlikely to help in the next 25 days. Soil moisture is below wilting point to 30 cm, so urea will not dissolve properly or be taken up, and there will be no growth response until significant rain falls. Urea applied to dry soil can volatilise if there is dew or a light shower, and when rain finally arrives the N may be leached or lost if the pasture cannot use it quickly.
Nitrogen also increases pasture demand for water, which is the opposite of what this farm needs in a drought. The better decision is to defer N until 10–15 mm of rain has fallen and pasture growth begins to respond. Even then, the response on hill country in a dry summer is uncertain and should be measured in a small area before committing the whole farm.
Buying balage at $320/bale is expensive: 900 × 0.85 = 765 kg DM per bale, so the cost is about $0.42/kg DM. That is high compared with pasture, but it may be justified to protect ewe condition and lamb survival. The 30 ha spelled paddock holds 60,000 kg DM, but grazing it now removes the lambing buffer, so it should only be used if the feed budget shows a genuine deficit after culling and balage are counted.
3. The neighbour's $2.10/kg offer is on the table. Should the owner sell now?
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No lambs have been born yet, so the offer applies to future store lambs, not to current stock. The owner should not treat it as an immediate option. The decision point is at weaning, in roughly 10–12 weeks, when lamb weights and feed conditions are known.
At that point, selling store lambs at 28–30 kg liveweight at $2.10/kg gives about $59–63 per head. That may be better than carrying lambs to heavier weights if feed is short, because the feed cost per kilogram of gain rises in a drought. However, the price offered now may not be the price at weaning, and the owner should compare it with the schedule and with the cost of retained feed.
For now, the priority is the ewe feed budget. Selling 300 cull ewes is a separate decision that reduces demand immediately and improves the feed position. The store lamb offer should be noted and revisited at weaning, with a comparison of sale weight, price and feed saved.