Soil health - linking it all together

Declan McDonald from DPI in Victoria recently visited our Making Good Better north and north western groups for discussion group meetings on soil health.
The northern group went first to Phil Spencer's property Sand Park where Phil gave us an overview of his farm management, which is focussed on improving soil health. Phil uses significant amounts of compost on his paddocks each year (usually 2.5-3t/ha), as well as a fish/seaweed soil drench. Whenever he applies N fertiliser it is mixed with compost first. He now has two paddocks set aside as areas where he is trialling no use of synthetic fertilisers (this year they are in peas and grass seed) at all - these areas received 7t compost/ha over two applications. Declan felt that Phil was approaching his farming in a very holistic way - that by managing for soil biology as well as nutrients, that he is ensuring that his soils will be "finely tuned and running on all cylinders". There was a lot of discussion about compost - in Victoria many farmers are now producing their own, with local compost turners for hire. We then went to Eastfield with Sam Bond, where we had a look at how Sam manages breaks in his cropping rotation to maintain soil health - a clover seed crop is the final "cash" crop in the rotation before ryegrass is drilled in. The circles are then fenced into quarters and used as irrigated fattening paddocks for lambs for 3-4 years. A saline area was also visited where Declan suggested using a thick layer of mulch as a trial to rehabilitate the saline area.

The next day Rachel took Declan to visit Mark Wadley's farm at Deloraine to discuss options for using effluent pond crust as a soil conditioner. As part of Mark's MGB activities, he has undertaken earth works so that the crust can be easily removed with an excavator and then stock piled for use as a soil amendment. Declan felt that the stock piled crust would make a good soil conditioner 'as is' but that biological activity could be improved with composting. Declan and Mark discussed options for a small scale composting trial - Declan advised that measuring the temperature profile is very important. Compost thermometers are around $300 and can also be used for measuring haystack temperatures. While in the area, Declan also visited Tim Schmidt's property to look at soil management in a difficult paddock. We then had a kitchen table chat with Colin and Liz Chaplin at Moriarty about the cost/benefits of incorporating composts and soil amendments. It was very interesting to hear Declan's long term perspective on soil biology. On the way to the airport, we discussed the 'tipping point' of NW ferrosol structural decline - both Decland and Pete Aird from Serve-Ag feel that when these soils get below 3% OC then there are negative feedback in terms of soil structure and management.