The couple, who are Beef + Lamb New Zealand Innovation Farmers, are aiming to lift the quantity – and quality – of drymatter grown on their medium hill country by 3T/ha – and are looking to legumes to help them achieve this.
Through plot and paddock-scale trials, they have identified the most cost-effective chemicals to control native grasses and allow resident clovers to flourish. Now, in the third year of their Innovation farm programme, they are looking at over-sowing with clover to augment the existing population on their trial area and implementing the specific management requirements of clovers – subterranean (sub) clover in particular.
Hamish says three significant rainfalls between late February and late March resulted in three separate strikes of sub clover. This meant they were managing clover seedlings at three different growth stages and so to ensure good establishment, they didn’t graze this area over March and April.
The Craws say they have been working on the theory that they have had 400kg of seed produced by allowing the sub clover to set-seed in late spring and early summer.
“Working on a 5% strike rate, we have 20kgs/ha of seed applied naturally – at no cost.“At a value of $10/kg, this is about $200/ha worth of seed,” says Hamish.
In late April, they flew 10kg of subterranean clover (3.3kg Antas, 3.3kg Woogenellup and 3.3kg of Capita) along with 1kg of white clover onto the trial area. This was to introduce new, higher-producing clover varieties and fresh inoculant.
This area was immediately grazed for seven days, using “hoof and tooth” to ensure good seed-to-soil contact and reduce some of the pasture cover that had accumulated in wake of the rain.
The introduced seed has struck well and Hamish believes the pasture sward, although slightly longer than he would have liked, actually provided a protective environment for the seedlings as they established.
“We have been really impressed by the number of plants we have seen strike and how the bare patches have filled up with sub clover – thanks to the spreading nature of the plant.”
This area won’t be grazed until at least the clover seedlings have three leaves- but quite possibly it won’t be grazed at all until late winter, early spring.
“We will just be keeping an eye on it and playing it by ear,” says Hamish.
Managing the sub clover
For the Craws, the focus will be on managing the sub clover so that it provides them with a bank of high quality feed in that early spring period.
As way of a comparison, the couple sprayed a further 7ha with glysophate and direct-drilled the seed into the sprayed area. This was to see whether there was any difference between the aerial application of seed and direct contact.