When we bought here in 2001 the paddocks looked pretty run down so we did some soil tests. The level of phosphorous and other nutrients was very low with the Colwell test for phosphorus only 5 ppm. A soil chemist commented that he had seen lower but those samples came from China. The suggested critical level is about 30 ppm.
The soil here is very prone to erosion with sodic subsoil. The eroded creek is plain evidence of the mismanagement in the past. Our soil chemist colleague and friend, Dr Roy Lawrie, suggested that we should never plough. The challenge of the erosion evidently scared many buyers away – the block had been on the market for four years.
Many paddocks had been ploughed and had erosion gullies. Even the steep hill behind the house had plough lines running straight up and down the hill. The pastures, if you could call them that, were pretty bare and comprised of broad leaf weeds and annual grasses like Vulpia and Fog Grass. Some hill paddocks which had not been cultivated had some better native grasses such as Danthonia and Microlaena but there were a lot of thistles and tussocks as well.
This is what Cadfor was like when we bought in 2001
Phase 1
We started spreading turkey manure to lift the phosphorus level. With fertiliser applied we started to get more herbage even if most was of limited value. In one paddock the Vulpia or Silver Grass, a fairly useless shallow rooted annual, just bounded away. To stop it seeding we stocked the paddock very heavily. We also used a slasher to control the weeds and rank tussocks and to put some organic matter back on the soil as mulch. We found as the phosphorus level increased some subterranean clover appeared. We did not sow it so the seeds must have been spread at some time.
At the same time we started to subdivide the paddocks so that we could manage our grazing intensity.
Phase 2
Most of our paddocks are now native grasses with subterranean clover. The phosphorus level after two heavy applications of turkey manure has reached 30 ppm or above. Some paddocks have had three applications. Generally our pastures are very pleasing (see photo below) and we won the Native Pasture section of the local Pasture Competition in 2012.
The Danthonia is pretty tough for cattle to eat because they need to break it off with their tongues (unlike horses and sheep which nip it off) but it makes very palatable baled silage. Microlaena which is so good for sheep is not as suitable for cattle because of its low growth height. One limitation of even the best native grasses is their inferior production in winter. Nevertheless our calves average 1.3 kg / day up to weaning. In winter we normally have to supplement with hay or silage.
Autumn drop calves on Microlaena / sub clover pasture July 2014
Up to now we have made only very limited introductions of improved grasses and with generally poor results due to a combination of our weed control technique and bad seasons. We have noted that isolated plants of ryegrass, phalaris and cocksfoot in our fertilised native pasture can produce more than twice the feed provided by natives. We conclude that if we want to be more productive we will have to sow more improved grasses.
Phase 3
Twelve months ago we started spraying some paddocks with Roundup and direct drilling improved species. Our weed control was more thorough this time. We sowed one paddock with cocksfoot in June 2013 which got flooded and failed. We sowed it again in September 2013 along with another paddock sown to Perun festulolium and got a good strike although there were some bare patches which might have been caused by cockchafer grubs. These pastures were grazed in summer and autumn this year. We sowed another to phalaris / cocksfoot / fescue / clover in April this year with some bare patches evident once again.
We have no intention of putting introduced grasses across the whole farm but we need enough winter production to reduce the need for supplementary feeding. By having a mix of grasses we can strategically spell the perennial grasses to allow seeding and to ensure maximum persistence and recruitment.
Cows and calves grazing on new cocksfoot pasture in autumn 2014
The introduced improved grasses are clearly superior. The Microlaena native pasture pictured in Phase 2 above is having its first grazing since March while the adjoining newly sown cocksfoot paddock has been grazed twice in the same period and will be grazed again shortly.
Aerial photo of Cadfor taken November 2013.
Silage is being made left of photo and in distance. Paddock sprayed with Roundup evident in top right. Other bare paddocks have been slashed post grazing. Note the severely eroded creek.
