Year-round attention to detail drives pasture productivity
21 September 2023
A well thought-out grazing operation helps David Kininmonth (pictured) manage ‘Mt Hesse’, a 3,550ha property in Victoria’s western district.
Lambing down 18,000 ewes and running 9,000 head of dry stock plus opportunistic cropping requires good planning and commitment to monitoring.
David uses grazing charts to manage his pastures, which allows him to track if he is overstocked or understocked and match stocking rate to carrying capacity. He was introduced to this tool at a Grazing for Profit training course.
Other important tools to understand production and help plan include:
- measuring weight gain
- monitoring dry sheep equivalent (DSE)/ha
- measuring pasture growth at the start and end of the season P
- pregnancy scanning helps them know the actual production and this helps them plan.
"Matching stocking rate to carrying capacity is something that's difficult to get right, so I work very hard at it,” David said.
Perennial pastures on Mt Hesse are mainly Holdfast GT phalaris, Australian phalaris, Quantum fescue and Reward perennial ryegrass/phalaris mix, all with sub-clover.
Here’s a look at the annual pasture management program on Mt Hesse:
The Kininmonths aim for 30% clover and 70% desirable grass over the whole year but try to maximise clover in spring for livestock growth.
“We use large mobs for short periods of time, then put our young stock on to get the production we need.
“Last year we got a really big spring and we spray-topped because the phalaris got away, so to retain sub-clover in those paddocks, we really had to aid the livestock to eat it down,” said David.
All the developed country is carefully managed but Mt Hesse has a few large paddocks containing old Australian phalaris (known as ‘haystack paddocks’) which are let go to seed.
“We'd rather graze as much as we can really well and let the pastures which are not as well developed just run up and destock them,” said David.
Late spring to summer
Pastures are feed tested in late spring/early summer to catch the declining megajoules of energy so pastures can be utilised before feed deteriorates.
“South of the divide when feed starts go off, it goes right off and you’re left with straw rather than plants which have high nutritive value. You can’t just add a bit of urea and away you go, it just doesn't work in our environment,” said David.
Spray-topping is a tool used to manage problematic weeds, particularly grasses and help preserve feed quality.
“We don't cut hay or silage – we mainly rely on grazing pressure to manage weeds and opportunistic herbicide manipulation. Herbicide use is pretty limited, but the grazing management is everything – it’s cheap and we own the stock,” said David.
Holdfast GT phalaris is grazed hard and then let run up to seed. David explains this avoids getting clumpy pastures.
“Then we'll crash graze it down to 1,200kg DM/ha to remove the residual dry matter. In the summer, we try to keep 90% ground cover.”
Paddock size is mainly between 8–14ha, with a lot of 20ha paddocks and a few 30ha paddocks to allow more control over the grazing system. All paddocks are fenced according to land class.
The Kininmonths avoid using management interventions in autumn which reduce food on offer (FOO).
“What we do in autumn affects carrying capacity over the winter and this affects our profitability. In spring, we know what we’ve produced and so can afford to make decisions around pasture management such as spray-topping,” David said.
He aims to have residual dry matter grazed down to 1000kg DM/ha by May to allow clovers to germinate.
“The old phalaris straw has an allelopathic effect [influencing the germination, growth and survival] on sub-clovers, so we want to get rid of as much as we can. We’ll put large mobs onto it for about a week and we'll take it right down,” David said.
Phosphorous fertiliser is aerially spread after the break so urea can be added and spreading costs reduced.
“We add a bit of urea to phosphorus fertiliser if we need a boost – the plants are already up and running and so can utilise the urea. If we had to put on nitrogen later, it would be a huge cost to the business. We do a lot by air because we can get it done in a few days and it's cost effective.”
During autumn, stock are locked up on the ‘haystack paddocks’ of older Australian phalaris which has been let run up to head. This allows the managed pastures to rest and grow to their target of 1,300kg DM/ha by June 1.
“A lot of people are containment feeding but there's a lot of things can go wrong especially with pregnant stock. If we get an early autumn break you tend to get a lot of disease in the sheep, feet abscesses and worm spread. I'd rather utilise big haystack paddocks with large mobs of ewes that are all well looked after,” David said.
David likes to have a maximum of 1,300–1,500kgDM/ha at the start of lambing on 22 June – this is the maximum needed because his pasture growth rate will carry eight or nine ewes/ha right through winter.
“The growth rate is driven by winter-active perennial grasses and clover which has put nitrogen in the soil in the previous year and the use and timing of fertiliser,” he said.
“We got foot abscess problems where we've had paddocks up around 1,800kg DM/ha. Having too high FOO is like being under grazed, but overstocked.
“If you've got 1,300kg DM/ha, the sheep will graze across the whole paddock but if it's 1,800kg DM/ha they graze a small area, so when they lamb, they're all jammed up together, selectively grazing the best pick.
“So, all you've done is increase your stocking rate over a very small area of your paddock.”
David said the biggest management breakthrough was realising the cold wet winter rainfall period was not the biggest limitation, but the greatest opportunity.
“Combining soil nutrition and smaller paddock size with winter active perennials which have amazing growth during our most reliable rainfall period and bringing forward our lambing dates has given us the biggest bang for our buck without a doubt.”