Home » News » Green, green grass of Camden
Green, green grass of Camden
From left Terry Kilday, Graham Kerr and Leo Donkers – making decisions and reviewing them based on data.

Green, green grass of Camden

Renewal of the pasture of a Canterbury farming business’s four farms inside four years was conducted like a military operation. Anne Lee reports.

If there was a catch phrase for Camden Group’s massive pasture renewal programme it would have to be go early and go hard.

The family owned Canterbury farming business is in the fourth season of what’s become an epic tale of mega-grass proportions.

It’s a story of bold endeavour, battle-like planning, triumphs, financial hurdles as the milk price fell through the floor, a plot detour and even the odd defeat.

And while its final chapter hasn’t yet been written, the spoiler alert is that the initial plot was right all along and a happy ending is now in sight.

The story began back in early 2013 with a gutsy call to renew a third of the group’s milking platforms in just one season followed by similar rates of renewal over the next few seasons so that within close to four years the full 800 hectares would be in new permanent pasture.

The grand plan aimed at very quickly improving the amount of home-grown feed, to rid the group’s farms of a significant proportion of the bought-in supplements that over time had crept into the system.

The increase in supplements, to almost a tonne of bought-in feed per cow, mirrored the slow creep of unproductive, matted, old grasses such as browntop, sweet vernal and Yorkshire fog back into the sward.

It’s the data, both physical and financial along with physical observation that fundamentally informs the team’s decision-making process.

Like most Canterbury dairy farms their history as dryland operations means the soils still play host to a rich seed bank of these old grasses.

Given any opportunity the sleeping old timers will stealthily awaken and invade.

Camden group general manager Leo Donkers says the renewal plan aimed to rapidly call a halt to these creeping invaders, quickly reversing the trend in supplement use and boosting the amount of high quality home-grown pasture harvested by cows.

One of the group’s farms, the 306ha Te Pirita property Willsden, is part of a benchmarking group with Lincoln University Dairy Farm.

Data collection, monitoring and analysis have always been part of Camden’s DNA.

Leo’s brother and partner in the business, John Donkers is also a farm consultant and operations manager Terry Kilday has a strong focus on recording and monitoring.

It’s the data, both physical and financial along with physical observation that fundamentally informs the team’s decision-making process.

Back in the 2012-13 season bought-in supplement on Willsden hit 3.3 tonnes drymatter (DM)/ha or 974kg DM/cow and, while those inputs had been growing, milk production had remained fairly constant at 450kg milksolids (MS)/cow and 1500kg MS/ha.

At the same time pasture monitoring was telling them new grass paddocks sown the season before were out-performing older pastures by a country mile.

With greater winter and early spring activity those paddocks were on a 14-day round while the rest of the farm was still out at 25-days.

Paddock records showed a range in production from eight to 19t DM/ha/year.

The team called in the experts and reviewed their data even more closely carrying out a detailed analysis of benefits and costs.

Armed with that information they decided it was time for serious action.

Agriseeds’ Graham Kerr says such a major renewal programme called for tactical planning well before spring.

The team dropped the stocking rate slightly and ensured they had extra supplement on hand.

The poorest-performing paddocks were selected, fertility checked and any drainage issues or other factors that could affect production dealt with.

The decision was made to do that first season’s renewal in four tranches starting in September with 41ha of a total of 90ha to be renewed sown in a short-term Italian ryegrass and 49ha sown into permanent pasture.

Two hits

The aim of going through a short-term Italian first was to give those old, invasive grasses two hits with the spray a year apart and at the same time bring some high-quality fast feed on to the platform.

In hindsight, given the extra pasture they grew in that first season they wouldn’t have been so conservative with stocking rate and supplement on hand.

The new paddocks averaged 2.4t DM/ha/year more in the first milking season (which included the four-six weeks they were out of grazing) than the bottom quarter of the farm production wise which meant they more than halved their supplement use, dropping it to 478kg DM/cow while maintaining milk production.

From June 1 through to when the paddocks were sprayed out towards the end of October to go into permanent pasture they produced about 1.7t DM/ha more again than older paddocks.

Buoyed by the success and with data to help make paddock selection decisions they also took out another 56ha of older pastures, spraying them out and drilling the Italian ryegrass, Tabu.

Analysis at the end of the 2014-15 season saw big benefits in terms of production although the gains were a little dented by an exceptionally hot, dry summer with high night time temperatures.

Still analysis of the renewal programme published in the 2015 proceedings of the NZ Grassland Association showed a 198% return on investment within season of sowing thanks to extra production and higher quality feed that was easier to utilise.

Then things went pear-shaped.

The payout plummeted in winter 2015 and cashflow was at an all time low.

As it was on other farms, the slasher was taken to the budget. Although the long-term case stacked up the lack of cash coming in meant the renewal project had to take a major haircut.

“We came up with three choices – one to let the Tabu run its course for another season, two was to put it into perennial which was the normal practice but at a higher cost or three was to undersow more Italian back into Italian.

“We just didn’t have the cash to go from Italian to perennial so we tried one and three and what we’ve found out from experience is that option one and three didn’t work.

“It was very disappointing – we ended up chasing our tail all season,” Leo says.

By leaving the Italian for another full season it went through a vernalisation process and the team were confronted with 42ha of pasture that by late November-December just wanted to run to seed no matter what.

“We ended up having to keep on topping. You’d mow them off and think they were right but they would just go back to seed,” he says.

So while they cut close to $50,000 out of the budget by taking options one and three in theory, additional silage fed through December cost close to $40,000 if the feed cost was valued at 40c/kg DM.

In reality it didn’t have an impact on cashflow as the silage was already on hand but it’s all part of the cost benefit analysis of the programme.

“We fed three times what we’d normally feed through December period – about 133kg DM/cow and 100kg DM/cow of that we could confidently put down to the effect of carrying those Italians through,” Leo says.

On top of the seeding problem Terry says letting the Italians go through to another year – whether they were undersown or not – ended up putting them a year behind.

“That’s driven by the fact that the browntop and weed species came back in a number of paddocks so we really had to start all over again with them.

“I think the weed burden and those older grasses coming back in just meant the undersown Italian just couldn’t compete early on,” Terry says.

“This programme, using the Italians, it was all about getting rid of the browntop and old pasture species with the double spray while at the same time giving a lot of extra, fast, high-quality feed during the process.

“People sow these Italians in different circumstances and they can do well for two to even three years but in this situation it was about going into these old, run-out paddocks with two sprays in 14 months to get on top of the old grasses.

“To get around the cashflow problem corners needed to be cut – and this didn’t work ,” Graham says.

Once they stopped seeding the existing Tabu gave very good autumn and winter growth so it wasn’t like they were no benefit, Leo says.

Camden’s comprehensive paddock records show that Italian ryegrass gave an average 1.7t DM/ha of additional feed after the first milking season (June 1 to October 31) and when this winter and early season growth is included for the second season, until it is sprayed out in October or November, the total additional feed is about 4.1 t DM/ha.


“Convincing the board we should get back into the programme this season really wasn’t a hard sell – the numbers speak for themselves,” he says.

On Willsden this spring they’re back into it with a vengeance and have re-sown 33ha in Italian and taken 13ha from Italian to perennial.

They’ve also sown 13ha in kale and fodder beet as they move to transitioning cows on and off winter feed on the platform.

“That’s like our annual in this programme. The paddock’s sprayed out for the fodder beet or kale and then it’s sprayed and worked up again to go back into perennial,” Terry says.

Counting the crop paddocks they’ll have 46ha to go out of Italian ryegrass or crop, into perennial next season.

But to allow flexibility, depending on conditions, what they might do is take some of that Italian back though Italian again by spraying it out and resowing it.

That’s because of the logistics of getting the perennial all sown in late October.

“Getting it into perennial is a longer job because of the way we cultivate paddocks and spend time getting the seedbed right. So you’ve got to have the weather on your side and contractors available at a time when you’re competing with fodder beet going in the ground,” Leo says.

Rather than put a paddock into perennial, spray-drilling it into Italian is a fast operation, much quicker to grazing, and they know provides feed with much higher metabolisable energy (ME).

The team are already talking about what the renewal programme will look like once the last big tranche of new grass is sown.

Graham says there shouldn’t be a status quo renewal plan where a set percentage of the farm is taken out each year.

“It’s about selecting paddocks based on performance and for that you need good records. Camden’s got very good records so it should really be a matter of looking at those and doing the numbers on bringing up the under-performing paddocks.

“It could be that’s equivalent to 15% of the farm or it could be 5%.

“Too often the area to go through renewal is set by the budget. We do 10% because that’s what’s in the budget – with no reference to paddock and pasture performance.

I think what the team’s seen here is that, aside from extenuating circumstances when a massive payout crash means there’s a critical cashflow situation for instance, pasture performance has to be the driver so you can make good investment decisions.”

Farm managers Glenn Jones, Willsden; Paul Whittaker, Chiswick; and Robin Hornblow, Prairie, in a paddock re-sown in Tabu Italian ryegrass in this spring. Robin says it had been left to do another season in 2015-16 and while it was difficult to manage last summer came out of the winter with the highest cover and great quality. It had three grazings before it was sprayed out and Tabu resown.

Going early

One of the keys to success in this large-scale renewal programme using short-term Italian ryegrass has been sowing it early.

As soon as the soil temperature hits 7-8C in mid-September it’s time to go in, Graham says.

“Italians and annuals will grow in temperatures 5C lower than perennials so 7-8C is ideal compared with perennials that really want temperatures to be up at 12C,” he says.

“We learned the lesson about going early in the first year because although the late-September-sown Italian was a little slower out of the blocks than the October-sown tranche, when we crunched the numbers the September-sown grew 0.5-0.7t DM/ha more than the October,” Graham says.

“It’s also important for us sowing three tranches that the first goes in early enough otherwise you end up getting into the worst time of the year from a feed point of view and you’re still re-pasturing,” Leo says.

One of the benefits of going early is that contractors are also more likely to be free at that time.

Spray drilling the Italians

Paddocks are hard-grazed to a 1400-1500kg DM residual to open them up then left a week to freshen for spraying.

An important part of this process is pastures are short when they are sprayed, which allows the grass-killing glyphosate 540 to get into the sward and coat the fine-leaved, low-growing older grass species such as browntop.

“This is critical. Often people wait till there’s a cover of 2800-3000kgDM/ha and spray then graze. But when you have this much pasture the chemical doesn’t get down to these short, low-growing browntop-type species and killing these is a key goal”

An insecticide such as Lorsban is applied with the glyphosate if there’s an insect risk.

The paddocks are sprayed and drilled on the same day with a disc drill used to direct drill the Tabu seed at a rate of 20kg/ha.

They’re then heavy-rolled straight away to close up the slots and get good soil-to-seed contact.

Slugs are checked and generally haven’t been an issue, so slug bait is laid around the perimeter of the paddock to kill slugs migrating from surrounding paddocks.

At first grazing or nip off a broadleaf spray is applied along with a dressing of 100kg/ha of urea.

For early sowings in mid September this may be eight to nine weeks after sowing and for paddocks sown in October first nip off is usually at six weeks.

From there the paddocks are in the grazing round.

The next two applications of urea are also about 100kg/ha.

Establishing the perennials

Paddocks are sprayed with glyphosate 540 and left about 10 days to two weeks to ensure a good kill and to allow for some plant and root break down and soil to loosen off the roots.

They are ploughed and worked down with discs and harrows until a fine, firm seed bed is achieved.

They’re then sown with a conventional disc drill that’s been modified to also include a broadcast system.

The seed rate is split with 15kg/ha of diploid perennial ryegrass Trojan sown through the drill and 13kg/ha of tetraploid perennial ryegrass Viscount sown through the broadcast application along with 3kg of white clover.

The broadcast system sows the seed between the drill rows giving a dense cover across the paddocks, leaving no room for weed species.

The paddocks are heavy rolled and at first grazing or nip off, a broadleaf weed spray is applied along with 100kg/ha of urea. The next two dressings of urea are also at a rate of about 100kg/ha.

Vernalisation and the seed battle

Vernalisation occurs when a cold period, such as winter, is followed by increasing day length, such as in spring.

The period of cold triggers the plant to send up seed heads and reproduce itself as day length increases.

When ryegrass is sown in spring it doesn’t go through a cold period until the following winter so it doesn’t seed until the following summer.

That means 13-14 months of new, high-quality, easy-to-manage pasture.

If ryegrass is sown in autumn the seed-free period is much shorter although Italian ryegrass cultivars are more winter active than a standard perennial and gains can still be made in drymatter production over the winter and through early-season spring growth.