The huge potential of good grass

Waverley’s Damian Roper is passionate about new grass. He believes the potential for increasing pasture performance on dairy farms using new varieties is largely untapped.

Damian and his wife, Jane, have been sharemilking 850 cows on the 260ha dairy farm owned by Grahame and Diane Lance for the past 10 seasons. The Ropers are amazed by the production gains on the farm from renewing the pastures.

During his time studying a Bachelor of Agriculture at Massey in the 1980s, Damian remembers “the Colin Holmes all-grass production method being drummed into me”. “When I was there it all seemed to be about grass, grass, grass, and now I understand why.”

Damian says there is huge potential on most dairy farms for increasing pasture production and that pasture is by far the cheapest way to feed cows. “I believe the potential for increasing pasture performance using new varieties is largely untapped.

“It is really encouraging to see production gains from on the farm rather than off the back of a truck.” Producing around 1220kg MS/ha/ year, the Ropers run a pasture-based system except for bought-in maize silage and what Damian calls “a sniff of palm kernel extract”.

They buy in 400t of maize silage each year with extra stored in the pit this year because of excellent grass growth in winter and early spring. An in-shed feeding system was installed last year, but the feed is there only to fill in gaps, Damian says.

“Every season, and especially in this current economic climate and low payout, you have to pay strict attention to all costs especially feed costs. We only supplementary feed to plug feed gaps - for example during prolonged dry spells or poor early spring growth.

“Most seasonal deficiencies can be seen on the feed budget so you can plan well ahead to fill them.” When the Ropers arrived at the Lances’ farm, after working for several years in the area, they thought the pastures were producing reasonably well until they began measuring with a rising plate meter and by grazing.

Like trading up on a new car

They started renovating pastures in 2000 and were impressed with the performance of the new ryegrasses and clovers. “It was like swapping a 1966 Vauxhall Victor (which did all right in its day) for a modern car with all the bells and whistles.”

Whereas the older pastures were producing 12t DM/ha/year, Damian says the new varieties can easily produce 15t DM/ha/year, a figure that was unheard of 10 years ago.

Damain says there is still no excuse for poor pasture management, whether under new grass or older pastures. He says the newer grasses are also higher quality, with an energy value closer to 12.5MJ ME compared with the older Cocksfoot-predominant pastures at 10.5MJ. There is a noticeable difference on the rising plate meter and in the vat, he says.

Pasture renewal plan is vital 

Once these results were proven, the Ropers and Lances formulated a pasture renewal plan in 2003. “We decided to actually design the renovation, to make it of more benefit to the pasture growth curve. “With a bit of thought into the farm’s pasture renovation we thought we could smooth out the peaks and troughs in the pasture growth curve, and have more consistent growth throughout the season.”

Damian says ryegrass varieties can be selected for early spring growth, late-spring growth, increased summer, or autumn/winter growth. He has targeted having one-third of each type of pasture, to capture the advantage of differing seed setting times.

By using different varieties with early, mid-range and late seed heading characteristics, only a part of the farm has pastures which are going to seed at the same time. “You can then fully concentrate on a third of the farm at a time with the grazing management, and then move on to the next third and then the next.”

Damian says the end result hasn’t been easy to achieve but they are almost there. “We are well on our way to having the perfect grass-based system for this area,” he says.

Ryegrass and clover mixes have been used predominately over the past nine years, although this year Damian has had a “play” with chicory. He sowed 1kg of chicory seed with 19kg ryegrass and 6kg white clover and is particularly keen to see how it performs in the sward over the summer.

He found the chicory easy to establish, but says it can be susceptible to weed spray. “The cows obviously really like the herb as they really went for the chicory in the sward first.” As well as renewing the pastures on 8% of the Waverley farm each year, Damian and Jane have implemented the system on their two Alton (coastal Taranaki) dairy farms.

They have owned these farms for the past three years and have lower order sharemilkers on them, Warwick and Lisa Holmes milking 320 cows on 96ha and Vance and Tiffany Davies milking 185 cows on 58ha.

During his time shearing in Australia and on regular visits to Jane’s home in South Australia, Damian noted the soil damage there from years of continuous cropping so he is a keen proponent of minimum tillage.

In conjunction with their farm owners, the Ropers investigated, bought and overhauled a secondhand drill and Damian uses it over around 200ha each year.

“I don’t call myself a contractor, but I’m happy to help out other farmers who see what is happening on our farms and ask for advice.” He is heartened by the swing to pasture renewal by dairy farms in the area and says the secret to good establishment is attention to detail, whether for a crop or new grass. The seeding rate is crucial, especially when sowing a mix of seed sizes, and more seed is often not better.

Treat young grass like a baby 

There are lots of variables which can make or break new grass, and he encourages farmers to get all the info and work through the issues step by step.

“Young grass needs to be treated like a little baby; it needs to be nursed through the first few grazings.”

He and Jane keep their calves on the farm until late May to give their new grass its first grazing.

Grazing residuals of 1400kg DM/ ha are targeted and Damian says that while there are no excuses for poor management on any pasture, new grass management must be spot-on right from the start.

Full potential begins in year 2 

In year one Damian says pasture growth will still outperform the older pastures; from year two onwards, once the clover is fully established, the pasture will begin to perform to its full potential. Because the new ryegrass cultivars are great performers they are “nitrogen junkies”, he says. “Just like a V8 supercar, you need to give them petrol and extra oomph to go fast.” He says soil nutrients must be monitored and recommendations acted upon.

With a 12-year pasture rotation plan, Damian says he is confident the tetraploid and diploid ryegrasses they have been using will perform for that long, barring bad drought, which tends to take a few years off the grass lifespan, as does pugging or Argentine stem weevil.

After the second grazing with some compaction and fertiliser the grass will be away, but once again Damian warns not to let it get too long and be prepared for it to grow twice as fast as older pastures.

Keep residuals low - new grass likes to be eaten right down, to at least 1500-1600kg/DM. Damian works on having it “the same height as a matchbox standing on its end, all over the paddock”. Otherwise dead matter will build up.

Damian says the nitrogen is crucial in the first year as the clover is still establishing and is not fixing enough N to feed the grass in the early stages.

Published courtesy of Country-Wide October 2009