Clever clover management boosts output at Tempello
Learning how to manage subterranean clover has allowed a Marlborough couple to produce more at the same time as reducing inputs. TONY BENNY reports.
Tempello Station has been in David Grigg’s family for 101 years. The 4800-hectare property lies between the Awatere and Wairau Valleys, climbing from 100 metres, just out of Renwick, up to 1000m in the hills south of Blenheim.
It’s mix of intensively managed flats and lower hill country and lightly stocked high run country and carries 10,495 stock units, 51.4 per cent cattle and 48.6 per cent sheep. There’s also 13ha in grapes, grown on contract.
Over the past 10 years or so, David and wife Jo have fine-tuned their system and by getting the most out of their sub clover they’ve upped total meat production from 60 tonnes to 76 tonnes, despite having fewer ewes.
‘‘It’s not a radical change in management, it’s just tweaking, putting up fences,’’ David says.
‘‘It’s reasonably radical, David,’’ Jo disagrees. ‘‘It’s not radical in terms of new ideas, it’s old stuff in a more precise way.’’
David’s father ‘‘threw subterranean clover seed out of the aeroplane in the 70s’’, but it wasn’t really until Tempello was a Beef + Lamb monitor farm from 2003-2005, that the Griggs really integrated it into their system.
‘‘Dick Lucas of Lincoln University taught us how to manage the stuff; he’s the one you’ve got to give most of the credit to,’’ David says.
An annual, sub clover can produce large amounts of dry matter and is self-sustaining, thanks to a heavy annual seed drop, but on Tempello it was getting over-powered by spring grass growth.
‘‘The clover couldn’t see the light, so there was no chance of building a good legume base,’’ says Jo.
‘‘Grass totally dominated, it went to seed and the feed quality went down. The sheep would hang on certain areas and not graze others and so when the rain did fall it was totally wasted.’’
The key to getting the pasture under control was fencing and on Tempello’s 600ha of ‘‘front country’’, the 100ha paddocks were subdivided to between 14 and 20ha. As well as an extra 35km of fencing, a reticulated stock water system was put in.
‘‘The blocks were certainly too big, you couldn’t get an even grazing pattern; they’d go to the same faces every time. You have to have fences and you have to have water to do it,’’ David says.
Part of the management system is to shut up some blocks in spring once every 10 years to create a seed bank. Given the chance, sub clover can set 10 tonnes of seed per hectare.
‘‘It’s a bloody clever plant. It’s like an extremely small sea egg with feelers out. It’s only the size of your fingernail and inside that is this tiny, hard seed and it just goes into the ground and sits there and waits for the rain,’’ David says.
‘‘It will germinate with the autumn rain and by the end of June it should be about six inches high with about five leaves on it. By then we’ve scanned and then you break-feed it really hard through the winter with twinning ewes.’’
During that time the clover is growing its root mass underground.
In July, the stock are taken off and kept off until summer.
‘‘You let it go mad through the spring, get its flowers, get its burrs up and then the burrs go in. By December 10, the burrs are into the ground far enough to be not damaged and you can graze it with cows and calves,’’ he says
Jo adds: ‘‘Once it’s established you can use that paddock ongoing in late winter to get the ewes lactating properly so we don’t have to put a crop in on the flat for twinning ewes pre-lamb, which we used to do.’’
Another thing the Griggs like about sub clover is its ability to fix nitrogen from the atmosphere. Today they don’t use any bagged nitrogen on the farm.
‘‘It fixes 25 units of nitrogen for every tonne of dry matter grown – so if you’ve got four tonnes of clover dry matter, you’ve got 100 units of nitrogen. And because the plant fixes it slowly over time into the soil, it’s just fantastic. And then when the clover plant dies off, as it does at the start of summer, the grass can use that nitrogen,’’ Jo says.
‘‘We don’t have to use urea. And as there’s 30 per cent of urea lost to the environment as nitrous oxide, this is a much more natural system.’’
The Griggs are aiming for a system that suits their summerdry environment. While lucerne can produce more dry matter, Tempello is too steep to get it established so subterranean clover is the next best option.
They are finalists in this year’s Cawthron Marlborough environment awards.
‘‘I think, personally, that it’s really important for sheep and beef farmers to demonstrate the positive things we’re doing for the environment,’’ Jo says.
‘‘We want to tell the story about dryland legumes and what a positive change it has been through understanding them better, setting up a system to make the most of subterranean clover production.
‘‘It makes a much nicer farm system to live within, in terms of not trying to produce when things aren’t growing.’’
David worries about the effect nitrogen is having on New Zealand waterways and is pleased to have minimised that on Tempello. A 3km laneway not only gives easy access to the yards, it also keeps cattle out of streams. ‘‘I don’t know if it’s helped or not, but I think it probably has,’’ he says.
While Tempello’s front country is highly productive, much of the hill country is less so and of the total 4800ha, only 2600ha is classified effective.
The central part of the property includes a 1600-hectare area of forest and rocky bluff systems which has been identified as a Recommended Area for Protection within the Wither Hills Ecological District.
‘‘We had Philip Simpson, the ecologist, come out and do a full report on the species there. It’s the largest remaining stand of dryland forest still intact in that area.’’
Bird species in the area include riflemen, South Island robin, tomtit, brown creeper, fantail, grey warbler, waxeye, bellbird, kingfisher, longtailed cuckoo, black shag, kahu and eastern falcon.
To help the native flora and fauna thrive, goats and pigs are being brought under control. Since 2009, a hunter has shot 4500 goats and station staff have accounted for 160 pigs. They haven’t done any formal monitoring but Jo says there’s been a huge visual improvement in the understory.
‘‘We’re quite into community education about the area so I’ve talked to the kids at school about it and we have the open day once every two years,’’ she says.
The open day, called ‘‘Tramp the Ned’’ is a climb to the 909m Ned peak, a return trip of between three and five hours.
‘‘We’ve had 1200 walkers. We do it as a fund raiser for the Fairhall school, but as it turned out people just love it and they’re really interested in the actual species up there.’’